”MWOWWMYM . ENREWR“ 9"" mu.“- m TO AVOID mes W“ °" °' EDUE DATE DUE DAT E DUE _____________. J ___/ f—I—I— "" usuuAnAflimdmmfiq’do” | W‘ THE DEVELOPMENT OF GRAIN-FEED STORAGE AND HANDLING SYSTEMS FOR LIVESTOCK FARMS by Bruce Aldus McKenzie AN ABSTRACT Submitted to the School for Advanced Graduate Studies of Michigan State University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Agricultural Engineering 1958 APPROVED: K) ' EQAW |l [loll l 2 BRUCE ALDUS MCKENZIE ABSTRACT Grain-feed handling on livestock farms is a highly repetitive operation that will Justify mechanization. Grain— feed handling methods and facilities on livestock farms are a hetereogeneous lot; scoop shovel methods of handling pre- vail; coordinated equipment arrangements for complete mechanical handling are difficult to find. Storage structures dating over several generations are still in use; new struc— tures are selected according to tradition, rather than function; both old and new building designs are planned with little consideration of mechanized handling. The locating of structures in relation to grain-feed preparation and dis- tribution appears to be done on a random basiso Some improvement in grain—feed handling efficiency on livestock farms can be made by modifying existing facilities and practiceso But such a study is an attempt to solve prob- lems created by wrong decisions in the past. More signifi- cant progress can be made by studying ways of avoiding such mistakes in the futureo The grain—feed handling systems presented in this thesis are a plan for the futureo They outline an organi— zation of buildings and equipment into an integrated system for storing, handling, and processing livestock grain-feed) ‘The systems are planned to permit a gradual or immediate transition from existing practiceso 3 BRUCE ALDUS MCKENZIE ABSTRACT A procedure is developed for analyzing grain-feed handling systems for livestock farms. This procedure is supplemented by the development of general design funda- mentals. Considerations in design that cannot be summarized into a fundamental are analyzed in terms of their influence under various circumstances. Grain-feed handling systems are developed that pre- sent a maximum practical opportunity for mechanized materials handling. These systems embody current and projected prac- tices.in_building types and storage and handling methods° Commercially available grain storage structures and handling equipment make up the primary system components. Investment and use cost schedules are presented for all components featured in the system layouts. Selected storage and handling systems and components are analyzed in detail to demonstrate a procedure for estimating cost. Although systems of processing grain are not analyzed, data sufficient for estimating costs are presented. THE DEVELOPMENT OF GRAIN—FEED STORAGE AND HANDLING SYSTEMS FOR LIVESTOCK FARMS by Bruce Aldus McKenzie A THESIS Submitted to the School for Advanced Graduate Studies of Michigan State University of Agriculture and Applied Science in partial fulfillment of ’ the requirements for the degree of MASTER OF SCIENCE \ Department of AgricultureJEngineering 1958 ACKNOWLEDGMENTS The author wishes to express his sincere appreciation and gratitude to the following individuals: Professor D. E. Wiant, Agricultural Engineering Depart- ment, under whose guidance and constant inspiration and encouragement this study has been conducted. Dr. G. L. Johnson, Agricultural Economics Department for his help in planning and executing this study. Dr. M. L. Esmay, Agricultural Engineering Department for his help in guiding this program and in the preparation of this thesis. Dr. D. E. McKee, Agricultural Economics Department; Dr. C. w. Hall, Agricultural Engineering Department; and Dr. F. H. Buelow, Agricultural Engineering Department, for their many ideas and suggestions throughout the study and thesis preparation. Mr. P. R. Schepers of the Consumers Power Company for arranging financial support for this study. Each of the many manufacturers and distributors of grain storage and handling equipment who gave willingly of time and data. Ann Brown, who suggested the duplication method used for this thesis and spent considerable hours experimenting 11 iii with techniques to attain a quality reproduction. My wife, Irene, for her encouragement and valuable help throughout this study and thesis preparation. TABLE OF CONTENTS Page LIST OF FIGURES. . . . . . . . . . . . . vii LIST OF TABLES . . . . . . . . . . . . . 'x INTRODUCTION. . . . . . . . . . . . . . 1 The Problem . . . . . . . . . 2 OBJECTIVES . . . . . . . . . . . . 7 , LITERATURE REVIEW . . . . . . . . . . . . 8 . General Labor Considerations . . . . . . 8 Farm Buildings . . . . . . . . . . . 12 Grain Handling Equipment. . . . . . . . 14 Screw Conveyors . . . . . . . . . 14 Chain Conveyors . . . . . . . . . l8 Bucket Elevators . . . . . . . . . 19 Pneumatic Conveyors . . . . . . . . 20 Grain Processing Equipment . . . . . . . 21 Ground Feed for Livestock . . . . . . . 23 Materials Handling Analysis. . . . . . . 27 System Design . . . . . . . . . . 27 Efficiency Analysis . . . . . . . . 32 Plant Layout . . . . . . . . . . 34 Cost Analysis . . . . . . . . . . . 35 METHOD OF PROCEDURE . . . . . . . . . . . 37 DEVELOPMENT OF SYSTEM LAYOUTS . . . . . . . . MO iv Page A Conceptual Framework. . . . . . . . . 4O Assumptions . . . . . . . . . . . 40 Functional Classifications of the Problem . 43 System Design Fundamentals . . . . . . 44 Summary of Design Fundamentals. . . . . 50 Other Considerations . . . . . . . . 5O Feed Mixing . . . . . . . . . . . 56 Grinding Cycle . . . . . . . . . . 57 Feed Distribution Cycle . . . . . . . 58 Presentation and Discussion of System Layouts . 59 Basic Plan . . . . . . . . . . . 59 Special Equipment Design. . . . . . . 65 Ear Corn-Shelled Grain Layouts. . . . . 69 Dry Shelled Corn-—Small Grain Layouts . . 89 High Moisture Corn--Shelled Grain Layouts . 97 PRESENTATION AND DISCUSSION OF COST AND CAPACITY DATA 101 Cost As A Measure . . . . . . . . . . 101 Equipment Costs. . . . . . . . . . 102 Equipment Horsepower and Capacity. . . . 104 Estimating Equipment Fixed and Variable Costs . . . . . . . . . . . . 108 Equipment Cost Schedule . . . . . . . 109 Storage Cost Schedule. . . . . . . . 117 vi Page COST ANALYSIS AND DISCUSSION. . . . . . . . . 128 An Evaluative Framework . . . . . . . . 128 Analyzing System Costs . . . . . . . 128 Other Considerations . . . . . . . . 131 System Cost Relationships. . . . . . . . 137 Storage and Handling Systems . . . . . 137 Other Cost Considerations . . . . . . l6O SUMMARY AND CONCLUSIONS . . . . . . . . . . 163 SUGGESTED FUTURE STUDIES . . . . . . . . . . 168 REFERENCES. . . . . . . . . . . . . . . 170 APPENDIX . . . . . . . . . . . . . . . 174 Figure l. 10. 11. 12. 13. LIST OF FIGURES A schematic drawing of the basic grain-feed handling system layout. Each layout is made up of ground level components combined into a unitized facility. . . . . . . . Options in grain storage structures and their relation to a grain—feed handling system. . Materials handling possibilities for each func- tion of a grain-feed handling problem. . . A swinging overhead carrier for easing the movement of portable elevators inside a building ~Schematic drawing of a one-way slope hopper- bOttom bin. 0 O I O I 0 O O I O O Grain-feed handling system with a six foot wide single crib, two shelled grain bins, and a 20' x 20' processing area. . . . . . . . Grain-feed handling system using circular ear corn storage with circular small grain storage. Grain-feed handling system using a 16' wide drying crib with circular shelled grain storage Grain-feed handling system with 16' drying crib and circular shelled grain storage. Crib unloaded from one end . . . . . . . . Grain-feed handling system using two 16' wide drying cribs with circular shelled grain storage Grain-feed handling system using two 24' wide drying cribs with four circular shelled grain storage. . . . . . . . . . . . . . Grain-feed handling system using a clear span ear corn crib and circular shelled grain storage Grain-feed handling system using two clear span cribs designed for tractor scoop unloading . . vii Page 60 62 64 66 68 7O 73 77 81 82 83 85 88 Figure 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. viii Page Grain-feed handling system for shelled corn and small grain designed for complete mechanical handling. . . . . . . . . 9O Grain-feed handling system featuring two clear span storages, drying,automatic grinding, and complete mechanical handling . 93 Grain-feed handling system with circular shelled corn storage, drying,automatic grinding,and complete mechanical handling . 95 Grain-feed handling system using high moisture corn storage with a vertical elevator . . . . . . . . . . . . 98 Grain-feed handling system using plastic- rlined round metal bins. . . . . . . . 100 Average fixed, variable and total cost curves for Layout 8a with l6-foot wide conventional construction drying crib without drying, processing,or feed storage equipment . . . 149 Average cost curves for Layout 8a with 24— foot wide conventional construction drying crib. Cost includes unheated air drying equipment but no processing or feed storage equipment . . . . . . . . . . . . 153 Average total cost curves for Layout 8a for tWo crib widths and two types of crib con- struction. Twenty-four foot widths include drying equipment costs. No processing or feed storage equipment included. . . . . 154 Average total cost curves for 16 and 24 foot drying cribs showing effect of a 3 per cent credit for field loss reduction due to drying (Layout 8a without processing or feed storage equipment). . . . . . . . . . . . 155 Average cost relationships for various levels of through—put for Layout 8a with a l6-foot conventionally constructed drying crib. One system is fixed at 83 tons capa- city, the other is variable in size from 83 tons to 250 tons capacity. . . . . . . 158 Figure 24. 25. Bushels remaining in circular bin after gravity removal through a center outlet in the bin floor. . . . . Cost per bushel in handling grain from circular storage by hand and with a 6—foot flat-bottom bin unloader . . .. . . ix Page 161 . 161 Table I. II. III. IV. VI. VIII. IX. LIST OF TABLES Percent Increase in Production Per Man-Hour for Selected Crop and Livestock Enterprises. Horsepower Requirements and Capacity Delivered with Pneumatic Conveyors-~Horizontal Conveying. Estimated Horsepower Requirement and Capacity for Selected Grain Handling and Processing Equipment Assumed Interest, Tax, Housing, and Insurance Cost Schedule for Straight Line Depreciation of Grain Handling and Processing Equipment-~Per Cent of New Cost per Year. . . . . . Estimated Yearly Depreciation, Repair, and Total Fixed Cost for Selected Grain Handling, Processing, and Conditioning Equipment--Per Cent of New Cost. . . . . . . . . Estimated Fixed and Variable Costs (Excluding Labor and Motor Costs) of Selected Grain Hand- ling Equipment . . . . . . . . Estimated New and Fixed Costs, for Single Phase Repulsion-Induction Electric Motors and Manual and Automatic Motor Controls Estimated Fixed and Variable Costs (Excluding Labor) of Selected Grain Processing, and Conditioning Equipment--Motor and Control Cost Included . . . . . . . . . . . Estimated Construction and Annual Ownership Costs of Selected Grain Storage Structures, Bulk Feed Bins, and Shelter Structures General Livestock Rations for Estimating Grain-Feed Handling System Storage and Capacity Relationships. . . Page 10 20 106 108 110 112 118 119 122 136 Table XI. XII. XIII. XIV. XV. XVII. XVIII. Cost Relationships for Static Components of Layout 8a Adapted for Batch Assembly without Processing or Feed Storage Equipment. . . . Cost Relationships for Variable System Com— ponents in Layout 8a Adapted for Batch Assembly without Processing or Feed Storage. Equipment. . . . . . Investment and Fixed Cost Summary for Layout 8a adapted for Batch Assembly without Processing or Feed Storage Equipment. Variable Costs for Layout 8a Adapted for Batch Assembly without Processing or Feed Storage Equipment--16 foot Drying Crib with no Drying Equipment . . . . . . . Variable Costs for Layout 8a Adapted for Batch Assembly without Processing or Feed Storage Equipment-—24 foot Drying Crib with Drying Equipment Costs Included. . . . . . Summary of Total Investment and Average Fixed, Variable, and Total Costs for Layout 8a Adapted for Batch Assembly without Processing or Feed Storage Equipment . . . . . . . . . Drying Crib and Grain Bin Sizes and Capacities for Cost Relationships Developed for Layout 8a Investment and Average Costs per Ton for Layout 8a with a 16 foot by 32 foot Conven- tional Construction Drying Crib Operated at Various Grain Through—put Levels . . xi Page 140 141 143 144 146 147 148 156 I. INTRODUCTION Handling grain and processed feed on a livestock farm is virtually an everyday Job. Out of the multitude of storage structures must flow the daily ration of grain to the feed lots. By basket or by scoop, in sack or in bulk, on truck or with tractor, this is feed handling. Coordi- nate the buildings, the equipment, and the work methods with an operating procedure, and the result is a system--a feed handling system. From an engineering point of view there are three ap- proaches that can be used in considering grain-feed handling1 systems for livestock farms. The first of these is to consider methods of improving systems existing on specific farms, utilizing buildings and equipment in use. The method would offer immediate results, assuming the analysis was meaningful, but would be somewhat limited in application due to the unique nature of each farmstead con- sidered. The study would concentrate heavily on problems created by past decisions rather than determine ways of avoiding such problems in the future. lGrain-feed handling as used here means the handling of that grain to be fed to livestock, either in a whole or processed form. Throughout the remaining text, grain handling and feed handling will both be used to describe such grain-feed handling, depending on which most aptly fits the discussion at hand. Feed in this context means only concentrate rations. 1 A second type of analysis would involve a complete re- jection of everything now existent in types of materials handled and methods employed, and would attempt to predict the system of handling grain in the future. The study would seek to outline new methods and components for systems of the future. Results would be of benefit to farmers only to the extent that the predictions became reality. A third approach would consider equipment and methods successfully used on livestock farms, and develop and analyze ways and means of combining these components and methods into new, more efficient systems. .Where necessary (and possible), new components or methods would be designed to complete a particular system. The latter method is the approach of the following analysis. Its scope lies somewhere between the previous two methods. It seeks to pick up the problem at the stage of solution presently attained on many farms, and to project this into a plan for future development. The Problem The grain handling facilities on livestock farms are a heterogeneous lot. Structures for the same grain often differ markedly in design. Units of origin dating over several generations still stand with new units. 01d and new buildings show little or no fore-thought of mechanical unloading. Storage facilities appear to have been located at random. Their only common bond appears to be that they are "on the farmstead." Out of all of this must flow the daily livestock ration of grain. This we have assembled that we may bring about the simple marriage of material in an animal's stomach. This is the objective. But what about the efficiency of attaining that ob- Jective? A 30 cow dairy herd will require approximately 50 tons of grain per year. If this is handled four times, 200 tons must be moved. A 25 sow, 2 litter swine operation con- sumes 200 tons of grain per year, or 800 tons to handle on a four-time-repeat basis. Four re-handlings may be conservative for many farms. At harvest time, a bushel of grain is generally moved from the harvester to a wagon, and then to storage. In prepar- ation for feeding, the grain may be removed from storage, loaded on a vehicle, hauled to mill, unloaded, handled through the mill, reloaded, returned to the farm, and un- loaded into storage. If the storage is not a self-feeder, the ration must be re-handled to be fed. Not all of these steps are involved on all farms, or with all grains. Some grain may be stored at harvest in self-feeders and fed direct from storage. On other oper- ations, grain handling systems will involve added steps attributed to several kinds of grain stored in different buildings or on different farmsteads. Obviously, some re-handling is unavoidable where grain must be processed prior to feeding. But needless re—handling represents unproductive effort and investment that could be devoted to other tasks or to leisure. With 30 to 40 per cent of the average farmer's time presently spent in routine chores, (2, 19), a highly repetitive operation such as feed handling must operate at top economical efficiency. Kleis (24) in a study of materials handling systems on livestock farms found ground feed to require the most handling time per ton of all materials studied. The per cent of total time spent in routine chores is not decreasing as fast as field time (19). In the period 1940 to 1956, production per man-hour in meat animals in— creased only 14 per cent, and in dairy 69 per cent (38). Measured on the same basis, hay and forage production in_ creased 118 per cent and feed grains 305 per cent. This is due in part to the fact that numbers of livestock have increased while numbers of acres of cropland have not changed materially. A larger share of the difference, however, can be attributed to the standardization of field practices as opposed to farmstead practices. With standardized field practices, manufacturers have marketed a multitude of machinery of many sizes and capacities. Both the market and the performance were reasonably predictable. Farmstead mechanization, on the other hand, must be integrated into existing buildings and the particular manage- ment practices in force. This means custom engineering with costly installation. Manufacturers have been reluctant to gamble on such markets and farmers hesitant to buy at the asking prices. The lack of accurate cost and return data has further limited progress. Farm building manufacturers have done little to help chore mechanization. Since they do not generally manufac— ture materials handling equipment, they have tended to sell buildings and leave the mechanization up to the farmer. The resulting system often falls far short of what could be attained in a pre—engineered package. The one exception is the grain drying packages offered in many prefabricated structures. Such packages undoubtedly came about because they enhance the sales possibilities. The long time nature of investments in farm buildings further complicates the problem. At best, one may be able to predict several years into the future. Farm buildings, on the other hand, generally last at least 20 years. Deci- sions must be reckoned with over considerable time, whether right or wrong. Ideas cast in concrete are difficult and costly to change. Grain-feed handling systems for livestock farms are needed that embody a more scientific integration of buildings 21nd equipment into a system for preparing livestock grain rations. The systems should permit a gradual transition from old to new, to permit economical use of sound existing structures. Construction should be possible as a completely new unit, or as a step by step project extending over several years. The systems should present a plan for the future. They should serve as a guide to farmers, extension personnel, power suppliers, and farm building contractors in designing grain handling facilities and systems. The results of the analysis should further serve as a recommendation to manu- facturers of buildings and equipment for pre-packaged materials handling systems. II. OBJECTIVES The general objective of this study is to develop grain and feed storage and handling systems for livestock farms. More specific objectives are: 1. The design of coordinated grain—feed handling facilities that afford a maximum practical opportunity for efficient materials handling on livestock farms. 2. The selection and design of alternative equip- ment combinations for mechanizing grain handling through the storage facilities. 3. The development and analysis of the costs asso- ciated with combinations of storage facilities and mechanized grain handling under several levels of grain through-put. III. LITERATURE REVIEW A search of technical and popular literature on materials handling on the farm finds references to many phases of the problem. Some of these works relate to over-all problems of system design, while others concen- trate on a particular component. The literature reviewed on the following pages is not a complete listing of all such references, but is rather a selection of those deemed most pertinent to the problem at hand. Most of the se- lections are drawn from the more technical works. The review is presented under six sections including: General Labor Considerations, Farm Buildings, Grain Handling Equipment, Grain Processing Equipment, Ground Feed for Live- stock, Materials Handling Analysis, and Cost Analysis. General Labor Considerations Routine chores performed in and around farm buildings require 7 billion man-hours per year, according to Ashby (1945). In terms of specific livestock enterprises, he places the amount of total time in chores at 80 per cent for dairy, 80 per cent for poultry and eggs, 40 per cent for swine, 30 per cent for cattle and calves, and 20 per cent for sheep and lambs. He predicts that 1 billion man_hours per year could be saved by better, handier farm buildings. Hecht (1955) suggests that since World War II, a figure approaching 40 per cent of total time for routine chores is more correct than 30 per cent. He states that the average farm worker is spending an increasing proportion of his total time on routine chores. Hecht attributes the rela- tive increase in routine chores to the fact that the reduction in chore time per head of livestock has been less than the decrease in man-hours per acre for crops. In addi- tion, numbers of most kinds of livestock have increased while acres of crop land has remained relatively constant. Data presented in the United States Department of Agriculture Agricultural Outlook Charts (1958) substantiate the statements of Hecht.' Cropland for the period 1920 to 1956 has remained nearly constant at 100 per cent, using the period 1947 to 1949 as a base. Numbers of livestock breeding units for the same period have demonstrated a generally upward trend. Starting at 90 to 95 per cent in the early twenties, numbers fluctuated around this level until an abrupt climb to a peak of 120 per cent during World War II. Dropping sharply to the 100 per cent level by 1948, the index again began to climb, standing at approxi- mately 105 per cent by 1956. Production per man-hour for crops and livestock, in contrast show wide differences in gains made in the period 10 1940 to 1956 (Table 1). While meat animal production effici- ency has advanced only 14 per cent, feed grain production per man—hour has advanced 305 per cent. TABLE I PER CENT INCREASE IN PRODUCTION PER MAN—HOUR FOR SELECTED CROP AND LIVESTOCK ENTERPRISES Livestock or 1910—1956 1910—1940 1940-1956 Feed Crops Per Cent Per Cent Per Cent Meat animals 25 11 14 Milk cows 89 20 69 Poultry 106 16 90 Hay and forage 137 19 118 Feed grains 349 44 305 Cooper, _t‘al. (1947), writing on the progress of farm mechanization, state that of the 21.2 billion man—hours spent on farms in 1944, 13 billion man—hours or 60 per cent were done by hand or with hand tools such as an axe, pitch- fork, shovel, hoe, et cetera. The authors state that 75 per cent of the man-hours spent with livestock is hand labor. They cite feeding, watering, and manure handling operations as problems needing improved systems. Searching for more specific labor requirements asso~ ciated with materials handling on livestock farms, Kleis (1957) reported data compiled from 320 Michigan livestock 11 farms. Considering 30 different materials handling oper- ations, Kleis classified the methods of performing these operations as eliminated, manual, semi-mechanized, mech- anized, and automatic. The operations on each farm were classified according to the methods employed. The time, tonnage, and equipment involved in each operation were obtained in consultation with the farm operator. Some conclusions in the study by Kleis most pertinent to the analysis at hand were: 1. Materials consuming the most handling time per ton: a. Ground feed--first of three. 2. The most highly mechanized handling is associated with: a. Small grains-—third of three. 3. General types of operations requiring the greatest handling time: a. Feeding or distributing. b. Removal from storage. c. Moving from storage to area of use. 4. Considering average annual tonnage involved along with the man-hours per ton, the materials TEQUiPing the most annual total time were: a. Ground feed—-first of four. 12 5. Materials handling operations conspicuous for the time required: a. Feeding ground feed-~second of seven. b. Moving ground feed from storage to feeding area-~third. c, Removal of ear corn and small grains from storage—-sixth, Kleis suggests that while some operations in handling most feeds are well mechanized, little consideration has been given to their integration into the total handling program. He suggests a need for engineering to bring about such integration. He reports a highly significant corre- lation co-efficient between the amount of materials handling mechanization and the over-all farm production efficiency. Farm Buildings Farm buildings are often the bottleneck in handling materials on the farm. The high investment requirements and relatively long life of farm structures present a static dimension to system planning. Mayer (1947) states that all farm building designs should be studied critically from the standpoint of the best utilization of labor used in the activities in each structure. The location and relationship of each farm structure should be studied with respect to other buildings and the total farmstead. 13 Carter (1953), writing on challenges in farm building design, makes a plea for a coordination of engineering thought with the science of production and the principles and practices of operation and management. According to Carter, research has demonstrated that engineering of struc- tures, methods, operations, and equipment can double the output per farm worker. The increased output comes about through reduced labor, increased yields, and preservation of quality. Carter states that changes to tractor power, hybrid seed, commercial fertilizer, et cetera, has placed new pres- sures on the farmstead physical plant and its design. In his opinion, much of the improvement in farm structures in the past has been in the form of details, additions, attach- ments,or new versions of traditional structures. He suggests that the greatest current need is that of a new attack to create entirely new facilities. The engineer, according to Carter, is charged with the responsibility of accepting new resources and anticipating new demands, rather than waiting until other pressures compel him to act. Carter foresees several obstacles that must be over- come by the farm building designer, namely, the relative permanence of farm buildings, and the natural resistance to change. He suggests that buildings should be considered on 14 the same basis as any other production tool. In his opinion, it is unfortunate that farm building improvements are classed as real-estate instead of as operating equipment. Grain Handling Equipment Most of the grain handling equipment for farms is de- signed primarily with in-to-storage conveying in mind. The host of portable units available with carriages are prime examples. Although most of these units can be used for out- of-storage handling, planning their use inside a centralized structure is left primarily to the individual. For the current analysis, the questions involving such equipment are three-fold. These concern (1) capacities versus speed, size, and angle of incline; (2) horsepower for the same variables; and (3) cost of ownership and operation. Screw Conveyors Millier (1957) presented one of the most complete works on screw conveyors designed for farm use. His studies in- cluded 4 and 6 inch diameter single-pitch screw conveyors, at angles of inclination from approximately 100 to 900 in 100 increments. Wheat, oats, and ground corn meal were the materials conveyed. Speeds from 300 RPM to 1000 RPM in increments of approximately 50 RPM were studied. Results of the studies are presented graphically in Appendix I. Millier concluded that auger horsepower varies 15 directly with the length of screw conveyor in use. Maximumcxnr— acity for a 6 inch diameter conveyor handling oats and wheat occurred at auger speeds of 750 and 850 RPM. Maximum capa- city speeds were slightly lower for 4 inch diameter units. The maximum horsepower was required for both units at a 450 angle of incline for wheat and a 600 angle of incline for oats. In tests involving corn meal, both the 6 inch and 4 inch units continued to give increasing capacity throughout the 1000 RPM maximum speed studied. Maximum horsepower was required in both units at an approximate 450 angle of incline. Paine (1955), writing on the design and application of equipment for conveying grain in-to and out-of flat bottom bins, suggests six variables to use in designing grain handling systems. These include (1) initial cost, (2) cost of operation and maintenance, (3) ease of operation, (4) flexibility, (5) adaptability, and (6) capacity. Paine outlines a system of grain handling for wide, flat storages. Primary features include a 9 inch open top screw conveyor suspended horizontally along the top of the building. A closed tube 6 inch inclined auger is carried on an overhead track such that the intake rests on the floor with the discharge positioned over the top conveyor. The inclined auger can be used for truck unloading, or in re- moving grain from the building. Outlets at points along the 16 top conveyor permit distribution of the grain at filling time. McKenzie and Ross (1957) studied a mechanical bin unloader for removing grain from round, ground level, flat- bottom bins. The unit can also be adapted to square or rectangular structures, although 100 per cent removal may not be attained. The unloading system includes a hori- zontal drag conveyor to withdraw grain from a hopper cen- tered in the bin floor. The intake is below floor level while the discharge is positioned outside the bin above grade level. In operation, the drag conveyor withdraws all of the grain that will flow by gravity to the floor hopper. When gravity flow ceases, the unloader is placed in the bin, in- clined on the remaining grain funnel. When energized, the unit, consisting of a single-pitch helicoid with a shield on one side, conveys grain to the center hopper. Working its way to the floor, the unloader propels itself into the grain pile by means of a friction wheel mounted on the outboard end. The unloader continues to rotate about the center hopper until the grain is removed. A permanent pivot pin installed over the floor hopper keeps the device in position. McKenzie and Ross point out that the unloader and the drag are both portable units, and can hence be used in 17 several consecutive bins. The system can be used for un- loading a shallow layer drying system consisting of a round metal bin with a false floor. Unloading capacity is com— parable to a 6 inch diameter inclined screw conveyor. Puckett(l957) studied a similar unloader. The unit he designed is intended for permanent installation in a flat-bottom bulk storage bin, for use with such materials as alfalfa meal and soy bean meal. The unloading system con- sists of a separately powered drag conveyor, installed similar to the previous system. The unloader is powered through a bevel gear assembly by a motor located in a chamber under the bin floor. Both components are perma- nently installed. The sweep screw in unshielded, and rotates so that the ascending side of the helicoid acts against the material mass. In operation, the drag carries material from the cen- tered, floor-level intake, while the sweep screw is inoper- ative. When bridging occurs and the drag hopper flows empty, a pressure sensitive switch actuates the sweep auger. The sweep continues to cycle until the bin is empty. Rotation of the sweep screw is controlled by the torque of the bevel gear drive, with an adjustable brake to add drag. An idler wheel carries the outboard end of the unit. 18 Chain Conveyors Horsepower requirement data in relation to size, capacity, and angle of incline is markedly lacking for chain conveyors. Mostresearchersappear to use an estimate based on manufacturers quotations, tempered by experience and judgment. Henderson and Perry (1955) present a general description of all types of conveyors used in agriculture. Theoretical equations for calculating horsepower requirements and capacity are presented for chain conveyors. However, in the author's judgment,this formula is so specialized in terms of the conditions under which chain conveyors operate on the farm as to render it of little value. Results in applying the method are based on so many assumptions that one may as well use the expedient method of modifying manufacturers' quo- tations. Euler (1955) used a measure for chain elevators that combines the width of trough and the tons conveyor per hour. He termed the measure foot—hours of elevator trough width. Based on observations of corn elevating systems on farms, he lists the capacity of chain elevators as 13.62 tons per foot- hour of elevator width. Kjelgaard and Cflver' (1957) report on a top conveyor for use in distributing grain in flat—type storage structures, The unit consists of a horizontal single chain flight l9 conveyor suspended horizontally in the peak of the structure. The boot of the conveyor extends outside one end of the building to facilitate loading. Grain can be lifted to the top conveyor with any conventional elevator. Multiple out- lets drop grain at points along the top conveyor, thereby distributing grain and foreign material. Bucket Elevators The capacity quotations for bucket elevators are generally considered more accurate than those for most other farm elevators. This is due in part to the fact that an angle of incline is not involved, plus the fact that the per bucket capacity is more predictable and constant. Henderson and Perry (1955) present a formula for calculating the capa- city of such elevators, along with a general discussion of their characteristics. Wiant and Sheldon (1953) present detailed plans for building and installing a vertical cup-type belt elevator. The elevator may be built in lengths from 10 to 50 feet, and in capacities from 150 bushels per hour to 400 bushels per hour. Complete instructions for fabrication are given, along with power requirement data. Wiant and Sheldon sug- gest that a well planned elevator installation should in- clude some provision for delivering grain to the various storage bins and some provision for carrying grain back by 2O gravity from bins to the elevator hopper. Complete recir— culation of grain is then possible. Pneumatic Conveyors Air conveying of grain and ground feed from the processing area to the feeding area offers a completely mechanized method. Sheet steel pipes supported overhead can place the distribution system completely out of the way. Kleis (1954) states that air velocities of 4000 feet per minute are necessary for satisfactory performance. He suggests that the optimum pipe diameter for a system is the smallest allowable for the desired conveying rate. The optimum diameter is not affected by the length of the pipe, which may be up to 300 feet. Horsepower and capacity data for pneumatic conveyors is presented in Table II. TABLE II HORSEPOWER REQUIREMENTS AND CAPACITY DELIVERED WITH PNEUMATIC CONVEYORS-—HORIZONTAL CONVEYING Pipe Diameter Horsepower* Maximum Inches per Conveying Rate 100 ft- Of pipe Lbs. per Hr. 6 1-1/2 55cc 5 1-1/4 4500 4 1 3500 *Plus 1/3 horsepower for each 1000 lbs. of material conveyed per hour. 21 Grain Processing Equipment Most of the recent research works involving feed processing equipment for farmslurnacentered around small, automatic, electrically driven units. Several commercial models have been developed and marketed, ranging in size from 7-1/2 horsepower down to 1 horsepower. Several variations in tractor driven grinders have also appeared on the market, with special emphasis on power- take-off driven units mounted on wheels. Many of these grinders are of the burr type. Forth, et al. (1951), report on the Feed—O-Mat system developed at the University of Illinois. This system consists of a 5 horsepower electrically driven hammer-mill, fed by a load-controlled mechanical feeder. A multiple channel web-type conveyor acts as a blending unit for small grains and supplement. The blending rate is con- trolled by varying the clearance between the traveling web and a calibrated bin outlet tube. A mechanical unloader for a converted section of corn crib is a part of the system, permitting automatic removal of ear corn at a rate controlled by the mill. The complete system grinds ear or shelled corn with small grain and supplement and blends the ration as it is ground. The unit, since it consists of separate components 22 to handle each part of the ration, can be fitted into nu- merous combinations according to the circumstance at hand. In my judgment, the Illinois Feed—O-Mat system has served primarily to focus attention and ideas on feed hand- ling problems. Efforts to merchandise the unit to farmers were apparently unsuccessful. This appears to be due to the initial cost plus installation cost associated with each sale. Modification of the storage structure to receive the unit is extensive. Without on-the—site planning and subse- quent installation by experienced personnel, results are unpredictable. Sales organizations are not prevalent in the farm field that can undertake such a complex merchandising program. Butt (1955) reports the results of performance tests on a 2 horsepower grinder-mixer. The unit consists of a 2 horsepower hammermill, to which is attached a 4 channel blending device for metering ration components. The blender is driven from the mill, and the feed rate of each channel is adjustable. Automatic shut-off in case material should fail to feed to one channel is possible with the use of series connected pressure switches located in each channel. A timer to shut the mill off at the end of a selected time period is built into the unit, thereby making it fully auto- matic. 23 It was determined that the mill would grind and mix a satisfactory ration for either swine or poultry when the meters were set for a suitable proportion. Proportioning is by volume, and was found accurate within 1 per cent by weight, the volume to weight ratio having been established for the materials‘processed. -Electric power consumption ranged from 0.151 to 0.663 kw-hrs. per 100 pounds of feed, depending on the dial setting and the amount of grinding required. Capacity ranged from 419 to 2086 pounds per hour. It should be pointed out that the 2 horsepower grinder- mixer outlined above will not grind ear corn, unless it is first pre—crushed. Too, the mill generally requires over— head hopper bins to deliver grain by gravity, although a mechanical feeding system is available for use with ground level storage. Ground Feed for Livestock _Several questions invariably arise when one discusses the value of grinding feed for livestock. The question is usually two-fold. First, "Does it pay to grind?" and secondly, "What type of mill is best?". The answer to the first question appears to depend on the class and age of livestock involved. .Wilbur (1933) studying milk production of dairy animals fed ground and 24 unground grain concluded that grinding did pay. The greatest quantity of milk per hundred pounds of feed was produced with what-Wilbur termed a medium-finely ground material. Gerlaugh (1929), studying the value of ground feed for 250 pound calves, found that the calves fed shelled corn consumed a greater quantity and gained more rapidly than calves fed ground shelled corn. The calves fed shelled corn did not pass whole kernels of corn until after they had reached 500 pounds in weight. Snapp (1948) reported a study of ear corn, shelled corn, crushed ear corn, corn and cob meal, and ground shelled corn fed to beef cattle followed by hogs. Average daily beef cattle gains were 2.52, 2.71, 2.59, 2.61, and 3.08 pounds, re- spectively. Feed per pound of gain (on a shelled corn basis) was 6.80, 6.57, 6.58, 6.48, and 5.95 for the five rations. Based on an estimate of 5 pounds of corn per pound of pork, the whole corn produced more total meat (beef and pork com- bined) than did the prOcessed rations. Snapp concluded that unless the price of fat cattle is considerably higher than the price of hogs, grinding of corn is not ordinarily justi- fied where hogs are available to follow cattle. In the absence of hogs, corn should be ground, as the larger gains made by the cattle will more than offset the cost of grinding. 25 Evvard,gt a1. (1927), studying corn preparation for yearling brood sows, concluded that ear corn and shelled corn were more efficient than ground ear corn or corn meal for wintering brood sows. All lots received salt plus 3/5 of a pound of supplement mix daily, plus the corn ration. Differences in gain on various rations were not great. Sows on the corn and cob meal made the least gain. There was little difference in the pigs farrowed from sows fed various rations. Garrigus and Mitchell (1935) reported a 3.5 per cent gain in corn as a source of energy when fed to five pigs weighing from 135 to 196 pounds. Morrison (1951) states that numerous experiments of ground versus whole corn for swine indicate that grinding will not generally pay, up to the usual market weights pro- duced. He cites a series of studies that indicate little gain for ground feed fed to pigs weighing up to 150 pounds. Thereafter, a saving of 6 or 7 per cent by feeding ground feed was attained, but this short feeding period will usually not justify grinding. Foster, 2£.§l- (1955), reported on the value of high moisture shelled corn stored in a hermetically sealed storage as a feed for hogs. Results indicated that corn stored at 27 per cent moisture content maintained its feeding value as a feed for swine. 26 Isaacs, 33 a1. (1958), found that high moisture shelled corn stored in a hermetic storage gave an 8 per cent greater daily gain than did 13 per cent moisture content dry corn when fed to two lots of 15 hogs each. The high moisture corn was stored in a conventional corrugated metal grain bin, with a sealed plastic liner. The initial moisture content of the corn was 25 per cent. The hogs fed the high moisture corn ate 9.2 per cent more corn on a 13 per cent moisture basis, but ate 19.7 per cent less protein supplement. All feeds were fed free choice. The feeding value of the high moisture corn was concluded to be at least as good as that of dry corn. In the author's experience in talking with swine farmers throughout Indiana, some of the results of feeding trials on swine fed dry corn may not be representative of situations cur- rently existent on some farms. With the advent of heated air dryers for drying shelled corn, the farmer has 13 per cent moisture content corn on a year around basis. This moisture content is necessary for safe storage. Several farmers feeding 13 per cent corn to hogs have remarked that although they can detect little gain in feed efficiency by grinding the grain, intake is increased. Some suggest that they can double intake, and hence rate of gain. Other farmers remark that the pigs may eat too 27 much supplement when fed free choice with the hard corn. Thus the economical balance of the ration is uncontrollable. .Studying the difference in grain ground by different types of mills as a feed for beef cattle, Kleis and Neuman (1956) concluded that there was no significant difference in gains of steers on 3 different 56 day feeding tests. The amounts of feed consumed were not significantly dif- ferent between lots fed grain processed by various millsc Materials Handling Analysis Numerous studies that relate to some aspect of mater- ials handling on the farm have been reported by agricul- tural and industrial scientists. The techniques outlined under such captions as plant layout, motion and time study, materials handling, activity analysis, process analysis, and operations research all contribute suggestions relative to the problem at hand. System Design Curry (1955) writing on the development of co-ordi- hated feed handling systems for farms, states that the design of feed preparation and handling systems involves the development or selection and the coordination or inte- gration of a number of separate pieces of equipment into an operating unit. 28 Kelly, gt a1. (1953), writing on the design of a live- stock physical plant suggest that the analysis must consider the flow of animals, feed, water, products, manure, and men. They state that the procedure in designing such facilities should be: 1. Determine the problem. Construct materials flow charts. Make a preliminary layout. Select equipment and machinery. Evaluate the design. Make the final selection of equipment and layout. 40.014er Design buildings for the proper environment for products, animals, materials, and men. Kelly, gt al., estimate that 84 per cent of the grain and nearly 100 per cent of the hay is fed in and around the farmsteads. They point out that while the industrial pro- duction plant is a somewhat static thing within a given production period, the farm livestock enterprise is contin— ually changing in terms of livestock numbers and size, feed volume, et cetera. While the industrial factory can reduce production and curtail costs to meet the market, the farmer must perform one feeding operation, whether he has 1 cow or 1000 cows. He in a sense still may have a full time job. Euler (1955), studying work methods for handling grain on Indiana farms, suggests that the entire process of grain 29 handling can be broken down into basic operations. These include: 1. Separation of grain from parent plants. 2 Conveying of whole or processed grain. 3. Storing grain. 4. Processing grain. 5. Holding feed. He concluded that Indiana farmers in handling over 10 million tons of grain per year could reduce costs from 9 to 11 per cent, mainly by organizing and mechanizing for greater work efficiency. The analysis provides rates of man and machine accomplishments for all operations in handling grain. McKenzie (1956) suggested a method of analyzing grain handling and processing systems. Grain handling from the storage to the feed lot was broken into four steps: storage, assembly, processing, and distribution. Two intermediate storage functions following the assembly and processing steps were listed as optional. By considering different equipment and methods at each step in the preparation of grain for feeding, alternative systems characterized as manual, semi- automatic, and automatic were developed. The analysis also presented some suggestions on combining different types of conveyors into a continuous power train. Suggestions for mechanizing storage unloading were also presented. 3O DeForest (1955) presents four principles of materials handling on the farm. These include: 1. Don't move it, or move materials as little as possible. 2. Handle large amounts. 3. Make flow continuous. Use machines and gravity. 4. Condense it. Reduce bulk and weight. DeForest suggests two reasons why farmers are reluctant to mechanize farmstead operations. .First, other investments offer more immediate benefits, and second, materials flow problems on the farmstead are more difficult to solve than mechanization of field operations. Materials flow is charac- terized as basically a problem in farm structures. .DeForest states that farmers need suggestions and methods to help plan the use of equipment and buildings into an integrated, engineered system. Buildings now on farms lack flexibility for conversion to alternative uses. There is also a lack of equipment designed for materials handling uses. Ross (1957), writing on the analysis of materials handling systems, suggests that very little effort has been made to integrate equipment and methods into a complete system. He states that systems engineering starts with an appreciation of the fact that any action or reaction in any 31 part of an over-all system induces a reaction in other system components. Ross states that any materials handling system which is successful must: 1. Contribute to a maximum financial return and/or decrease the work involved in operating the farm. 2. Conform to the existing conditions imposed by topography, building layout, and seasonal vari- ation in work. 3. Be psychologically acceptable to the personnel involved in the work. 4. Be simple and safe to operate. 5. Be functional. The study conducted by Ross considered materials handling on a 280 acre Indiana grain-hog farm. Data were first collected on existing farm practices. Process charts were developed for the existing layout and for several modi- fied programs. .Each program was then equated in terms of time, human energy requirements, and capital investment. .Ross concluded that process charts were a satisfactory method of analyzing farm materials handling problems. He suggests this method as particularly useful in evaluating human energy requirements. 32 Efficiency Analysis Winter (1956) discussing how to make an efficiency analysis, suggests that the first step should be to estab- lish an objective. This may be cost or labor reduction, or improved service or quality. The areas outlined as most profitable for study include those with high labor require- ments, costly operations, expensive processes, critical quality preservation characteristics, excessive in process storage, excessive materials handling, and/or an unsatis- factory flow of materials. Winter suggests that any study should first attempt to increase efficiency without the addition of new equip— ment. The second step should consider the substitution of new equipment, coupledwith the proper work methods layout, and materials handling. The final step involves the devel- opment of totally new equipment and techniques. In using process and flow charts in an analysis, Winter suggests that the questions of why, what, who, where, when, and how, be asked of every detail. Can transportation be eliminated, distances shortened, sequences changed, or back-tracking eliminated? Further, can storages be elimi- nated, reduced, or relocated? Winter outlines a number of principles to keep in mind in materials handling. These include: 33 Materials flow.-—Speed is increased and costs re- duced when material is moved directly and through the shortest possible distance. The ultimate is continuous flow. Mechanical equipment.--Use horsepower instead of man-power. The total cost of equipment must equal the cost of the man-power before substitution is economical. Unit load.--The larger the load, the more effici- ent the materials handling. Flexibility.—-Use one unit for as many jobs as possible. Equipment in use.--Reduce idle time to a minimum. Performance.--Select the most economical and practical unit available. Equipment replacement.-—Replace present equipment with more efficient devices provided the increased productivity will more than offset the cost of the charge. Safety.—-Safe work means increased productivity. Facility layout.-—Layout has a direct influence on efficiency. It is an integration of equipment, materials, work centers, materials handling, and labor utilization. A poor layout presents the use of modern equipment because of unadaptability. 34 Vaughn and Hardin (1949) in their book on Farm Work Simplification state that the basic consumers of labor in farming are (1) movement of the hands and body while the worker stays in one place, (2) movement of the worker from place to place, and (3) the movement of materials and equip- ment from place to place. A summary of the most important principles concerning work that involves the movement of the worker from place to place includes: 1. Have buildings and work areas close together. Provide for circular travel routes. Use gravity to move materials. Provide wide smooth alleys and doorways. Locate tools and supplies near work. Combine and rearrange jobs. Plan to end one job where the next starts. Haul maximum loads. \OCIDNmU'l-Il‘wm Work at a reasonable speed. Plant Layout Immer (1950) suggests that good plant layout means placing the right equipment with the correct method. These should then be located so that a product unit can be processed in the most effective manner in the shortest possible time. 35 Hall (1958) presents several methods that may be used in determining the location of grain handling facilities on a farm. One approach is called the center of moments or center of gravity method. Given two quantities of feed to be fed at two separate locations, the method seeks to locate a point on a line between the two feed lot locations such that the weight of the ration times the distance moved is equal for both feed lots. Hall points out that the center of moments method gives an erroneous answer. A ton-mile figure lower than the value for the center of moments analysis can be attained if the storage facility is moved to one feed lot. The facil— ity should be moved to the feed lot using the most total ration. Such a layout gives a minimum ton—mile value. Hall presents a general analysis for minimizing ton- mile relationships with three feeding locations. A general equation is developed which can be solved by trial and error . Cost Analysis A comparison of costs is one of the most realistic measures of farm practices. Although a cost analysis generally presents a very static view of a problem, the cost estimates so obtained are valuable guides in decision making. 36 Bradford and Johnson (1953), writing on farm machinery costs, state that the underlying economic principles with respect to the profitable use of a machine are no different than that of other production factors. This means that the marginal cost of using the machine must be equated to its marginal value product. Marginal returns include the labor saved, the marginal physical product, timeliness, and the increased product quality. Heady and Jensen (1954) writing on the nature of machine costs in farming express their thoughts in terms of total costs and variable and fixed costs. Variable costs are those which vary with machine use, such as fuel and labor. Fixed costs, on the other hand, are those that occur irrespective of use, such as interest, insurance, most depre- ciation, taxes, et cetera. Heady and Jensen present a discussion of the costs that must be considered in evaluating the purchase of a given machine. They state that only the additional cost resulting from a given purchase should be considered. This is, then, really a marginal cost which is computed from the additional cost associated with the use of an additional input unit. A detailed discussion of costs that should and should not be considered in estimating the costs of a new machine is presented. IV. METHOD OF PROCEDURE The scope of the grain-feed handling problem consid- ered in this analysis includes the system from the in-take of the in-to-storage elevator to the common output point of the out-of-storage conveyors. The problem definition permitted consideration of a maximum number of factors ex- erting influence on the make-up of handling facilities without consideration of unrelated fringe factors. The step by step method of procedure was: 1. A review of previous investigations of materials handling systems for livestock farms was made to locate usable data and workable procedures. Manufacturers of prefabricated farm grain storage structures were contacted for information on units available, storage capacity, and cost. Visits were made to two manufacturers in Michigan, one in Illinois, and one in Indiana. Three representatives came to the campus. A survey was also made of grain storage plans available in the Agricultural Engineering Plan Service. Cost estimates for selected structures were formulated. A summary cost schedule was then prepared for all structures. 37 38 Visits were made to three manufacturers of grain handling equipment located in Illinois, and to one in Michigan. In addition, two representatives in the Lansing area were visited, along with con- tact by mail to an Indiana manufacturer. The manu- facturersselected were considered representative of grain handling equipment designed for farm service factors. Data collected included units available, estimated capacity and horsepower re- quirements, and retail costs. The equipment included chain drags and elevators, chain and belt bucket elevators, and screw conveyors. Manufacturers of grain processing, mixing, and bulk storage equipment were contacted by mail. Data similar to that for handling equipment were obtained. Summary cost schedules were prepared for all equipment. Agricultural Extension Service and Experiment Station personnel were contacted for information on recommended livestock rations and management procedures; also, information was obtained con- cerning livestock—grain enterprise combinations representative of Michigan farms. The data were used in the preparation of theoretical system requirements. 5. 39 A criteria for the design of grain-feed handling facilities was formulated employing the writings of researchers and feed handling authorities as a guide. Using the design criteria, available buildings and equipment, and livestock-grain enterprise combinations, grain storage layouts were devel- oped. Each layout included a corn, small grain, supplement, and ground-feed storage area, along with space for on—the-farm processing of grain. Where new equipment or building components were needed and unavailable, preliminary designs suf- ficient for cost estimates were prepared. Total cost relationships for storage-processing layouts and alternative equipment complements were prepared for several levels of grain volume and ration requirements. Results were analyzed and summarized. V. DEVELOPMENT OF SYSTEM LAYOUTS A Conceptual Framework Assumptions The first step in outlining a conceptual framework for consideration of a problem is to define the basic assumptions upon which the analysis is based. In the development of the grain-feed handling systems covered in this analysis, the following assumptions are made: 1. The handling systems must be designed such that they can be built component by component, over a period of years. 2. Each system must provide space for on-the-farm grinding. 3. The maximum practical degree of mechanized grain handling must be possible in all systems. 4. Only those grains destined for consumption by livestock need be considered in the system design. This includes purchased livestock feed supplies. Construction by components. This assumption is nec- essary to instill realism in the systems developed. Most 40 41 farmers who use the results of this analysis will have some sound grain storage structures and grain handling equipment on hand. This assumption insures that the systems designed will present an opportunity for economical use of such com- ponents. On-the-farm processing. This assumption is necessary because such processing is always an alternative to commer- cial service. Some operators may not desire to grind, either on or off the farm, and others may not find it econ- omical. 0n the other hand, if the size of livestock enter- prises continues to grow, such processing may be feasible within the life of the facilities. Too, commercial service is a variable factor. What is satisfactory today may be undesirable tomorrow. There is another line of reasoning behind the one—the- farm processing assumption. In the author's opinion, the long time trend in livestock feeding is to a complete, pre- pared ration. Several reasons are offered in support of this opinion. First, most animals utilize a processed ration more efficiently (14, 32, 36, 42). Second, by pelleting processed feed, utilization by the animal appears to be increased, while wastage is reduced. Third, with the trend toward drylot feeding, the complete, prepared ration offers one material to handle at feeding, instead of two or three. Hence, mechanical feeding is simplified. 42 Finally, a free choice system of feeding, from an economic point of view, offers little opportunity to adjust the ration to cost and price situations. A complete pre— pared ration, in contrast, presents an opportunity for week by week modifications in feeding. This permits the oper— ator some adjustments in the ration and growth rate to meet varying feed prices or market situations. By giving more control over growth rate, a complete ration offers a more exact utilization schedule of livestock facilities, a problem of increasing importance in the more intensified enterprise of tomorrow.1 Maximum_practical mechanization. This assumption is a hedge against the decreased labor supply and increased mechanization foreseeable in the future. The possibility of complete mechanical handling at some future date is thus assured. This assumption also permits an estimate of the maximum mechanization considered practical at the present time. 1Although this discussion of complete prepared rations does not preclude the possibility of incorporating forages with grain in a ration for ruminate animals, it is not with- in the scope of this analysis to consider such systems. It appears to the writer that such consideration would place an entirely new and as yet relatively unknown dimension on feed handling system design. This is all the more reason that such practice should be followed closely in the future. 43 Grain for livestock. Limiting the system design to grain for livestock is necessary to allow freedom in the design of facilities. It is the day by day unloading of grain structures in the preparation of livestock feed that is the heart of this analysis. Cash grain storage tends to be unloaded once per year. Consequently, the need for mechan- ical handling is substantially different. In addition, there is merit from a grain sanitation standpoint to have each grain storage totally separate from other grains. Functional Classification of the Problem In a previous paper (28) on the subject of grain handling for livestock farms, the writer outlined a func- tional classification of the problem. The classification consisted of dividing the grain-feed handling problem into functions of storage, assembly, processing, and distribution. Such a division offers several advantages. First, it breaks the problem down into components that are more easily analyzed. Secondly, mechanization opportunity exists with- in a given function that can be approached quite independent of other aspects of the total problem. Indeed, it was just such an independent component approach that has created the problem with which this analysis is concerned. Suffice it to say that independent does not mean unrelated. Thirdly, such a functional division is not unlike an actual investment program in a grain-feed handling system 44 on a livestock farm. It is a "jig-saw puzzle" approach, and can be used in planning and building a system step by step, with each investment a part of a future whole. System Design Fundamentals An analysis of grain-feed handling facilities under the functions outlined above serves to focus attention on some general design fundamentals. For instance, consider the effect of distance on the operation and performance of a system. Effect of distance. There are two alternatives in the layout of storage and processing facilities. One is to sep- arate some or all component structures, and the other is to integrate buildings into a combined facility. Consider the problem of assembling a batch of feed for processing under each layout. With the scattered layout, a transport vehicle would generally be used to travel from storage to storage and collect the ration components. If accurate weights are desired, a return to a common scale location is necessary between each load—out. Once the batch is loaded, it may be transported to a commercial mill, or to the on-the—farm processing area. It should be noted that the method of processing is not influenced in any significant way by the system of storage unloading or batch assembly. 45 In contrast, with the storage facilities as an inte- grated unit, the vehicle is pulled into a central drive-way, and all ration components assembled from this one location. Scales for weighing can be located in the drive. The storage unloading system can be the same as before, but the grain is unloaded directly into the processing area. It may be scooped onto the vehicle, or discharged into the processing conveyor system. The latter may consist of the same elevator used in loading from the scattered storages. The conclusion is that distance between storage units in a grain-feed handling system simply adds to the cost of operation.1 The first fundamental in the design of grain- feed storage and processing facilities is: MINIMIZE DISTANCE. Distance is a factor in the development of other fundamentals. The scattered layout involves the use of storage unloading devices, conveyors, and/or elevators at each location. These units must either be moved or multiple units or methods employed. The former involves considerable set-up, knock-down, and transport time, in addition to the lugging and lifting involved. Multiple units or methods mean increased costs and/or varying efficiency. In the centralized layout, distance between structures approaches a minimum. Movement of conveying and elevating 1The increased fire risk and grain sanitation hazard of centralized facilities are considered of minor importance. 46 devices is reduced, along with set-up and knock-down time. The fact that permanent devices may be installed to facilitate expedient set-up of multiple use units further complements the central layout. The second fundamental is: MINIMIZE SET~UP AND KNOCK-DOWN TIME. .Equipment use. The previous discussion in formulating the second fundamental developed most of the thoughts for the third. One grain handling device can be used for a num- ber of different handling operations, provided it is less work (and cost) to so use it than to employ a second method or device. The centralized storage system places all oper- ations within a radius serviceable by one unit. The third fundamental is: DESIGN FOR MULTIPLE USE OF EQUIPMENT. Manepower use. The fourth fundamental involves the use of man-power. A man is a complicated device. To build into a machine all of the things he can do has to date been impossible. But as a producer of horsepower, he is next to nothing. The average man can develop approximately one-tenth horsepower. :Working ten hours, he can perform one horse— power-hour of work. A one horsepower electric motor in one hour will perform the same work, and consume approximately one kilowatt-hour of electricity. .A kilowatt-hour costs ap— proximately 2% on an average Michigan livestock farm. This A I I‘ll (‘I .‘I’ A ‘II. I. \'|[.li 4", 47 means that a man is worth 2% a day as a producer of horse- power! All that he is worth above 2% per day must come from above the ears. This should be a sobering thought to any thinking farmer. Man should always be used EAEEE as a thinking device. This he can do as nothing else can. In terms of grain-feed handling system design, he should be used first to EDAEE; second as a floating control device, third as an expediter, fourth as an agitator, and last as a producer gt horsepower.l The fundamental to keep in mind can be stated as: USE MAN-TIME FIRST TOGHINK AND LAST FOR POWER. Processing system. A fifth fundamental involves the design of the processing system for on-the—farm grinding. Many authors have expounded on the merits of continuous flow in processing. Although this is a fundamental prin- ciple of materials handling, it appears unrealistic to the writer in terms of reality on the farm. 1This sequence in the use of man-time can be turned around and used as a guide in the mechanization of any operation. The mechanization would proceed as follows: Remove the drudgery. Mechanize all handling. Apply simple on-off control. Integrate the control system. Introduce automatic programming. \fi-P—‘UJIUH 48 In the first place, continuous flow implies flow over time. Yet the per hour feed requirements on a livestock farm are, relatively, very low. This means either of two alternatives: Use a very small unit many hours per day, or a larger unit a few hours per week. The former represents a difficult concept to sell to farmers, because it is con— trary to most mechanization decisions on field crops. The unavailability of successful continuous systems at a reason- able price does not enhance the selling task. To set up a continuous system of processing for rela- tively short time operation amounts to inefficient use of a large device. The system must be the same for 10 minutes or 10 hours of automatic operation. A preferable approach to grain processing on the farm, in this writer's opinion, is to process in batches. A batch system of processing offers several advantages. In the first place, it is adaptable to any type of mill, manually supervised or automatic, small or large. In addition, batch processing avoids much of the automatic control nec- essary for continuous flow assembly. Each batch gives an automatic check on ration formulation, an important consid- eration in formulating high potency feeds with any so-called automatic device. Further, high cost accurate measuring devices can be concentrated into one unit for batch processing 49 permitting purchase of a higher quality, more reliable design. Where weight by volume gives sufficient accuracy, measurement is greatly simplified. Finally, most farm processing centers must have a central conveyor system for handling in—to—storage of grain, as well as out—of-storage load—out or processing. This con- veyor system can usually be fitted into a batch make—up arrangement with little additional cost. In practice, a batch system of processing should be designed for manually supervised, speedy, batch assembly. This is the operation that requires the thinking, planning, and scheduling. This is good use of man-time. Processing may then be completed with a mill of sufficient capacity to justify supervision, or with a small automatic unit. The design fundamental is: PROCESS IN BATCHES. EMPLOY HIGH CAPACITY, MANUALLY SUPERVISED BATCH ASSEMBLY. Long-range planning. The last fundamental simply accounts for the long life of farm structures. Mechan- ization today will be sub-standard tomorrow. Competitive volume today will be too small tomorrow. Methods today will be outmoded tomorrow. The fundamental is very general and can be applied to any materials handling system: PLAN IN AN OPEN-END MANNER FOR FUTURE GROWTH AND ALTERNATIVE ACTION. 5O Summary of Design Fundamentals l. Minimize distance. 2 Minimize set-up and knock—down time. 3 Design for multiple use of equipment. 4. Use man-time first to think and last for power. 5 Process in batches. Employ high capacity, man- ually supervised batch assembly. 6. Plan in an open-end manner for future growth and alternative action. Other Considerations The method of materials handling, the method of feed mixing, and the frequency of feed grinding and distribution are of importance in the design of feed-grain handling facilities. The question of handling methods involves gravity versus mechanical systems. Although this question cannot be sufficiently answered at present to permit sum- mary into a design fundamental, some general guides in the use of gravity and mechanical handling methods can be stated. The method of feed mixing, and the frequency of feed grinding and distribution each involve options that may be equally sound, depending on circumstances. Gravity and mechanical handling. Handling by gravity flow is often recommended in the design of materials handling systems for farms (9, 39). The implication appears to be that since gravity handling involves a natural phenom- ena, it is thereby a preferred method. However, gravity 51 flow is generally not attained free of cost. A structure must be elevated and/or hoppered to attain such flow. The cost of these features must be charged to storage unloading. The indiscriminate uSe of gravity bins in a grain-feed handling system may prove costly. Elevating a bin and hoppering a bin should be consid- ered as two different but complementary methods of storage unloading. An elevated bin normally is designed to discharge above grade level, usually at a height sufficient for grain- feed load-out without rehandling. By elevating the structure, all material is discharged that will flow by gravity to the outlet. A hopper bottom, in contrast, is designed to prevent any repose of material in the bin, thereby bringing about complete removal. Elevating a bin thus avoids the use of grain-feed elevating equipment. Hoppering, on the other hand, is an alternative to the use of a mechanical, flat- bottom bin unloader. Elevated versus ground level bins. A ground level, flat-bottom bin unloaded with a mechanical grain-feed elevating device is an alternative to an elevated flat- bottom structure unloaded by gravity. To be strictly comparable, the grain-feed elevator should deliver the same quantity of material at the same rate and height as the elevated bin. Assuming both bins are of the same dimensions, 52 the quantity of material that will flow to the grain outlet is equal. To attain maximum gravity flow from one dis— charge point, the grain outlet with either bin should be located in the center of the bin floor. Several conSiderations are important when comparing gravity handling from an elevated bin with mechanical handling from a ground level bin. First, to attain gravity flow, every bin must be elevated, thereby involving dupli- cate investment. The mechanical system, in contrast, can be portable for use on any number of ground level units. Secondly, elevating a bin increases the height of the bin inlet, by an amount roughly equal to the support height. Equipment length necessary to fill the bin must be corres- pondingly increased. In selecting grain elevators for use for both in-to and out-of storage grain handling, the greater height of in-to-storage operations generally deter- mines the length of the elevator. The over-all lower inlet height of the ground level structure reduces the elevator length, and hence cost. Flat versus hopper floors. The use of a mechanical unloader in a flat-bottom bin to remove material that reposes on the bin floor is an alternative to the con- struction of a hopper-bottom for complete gravity removal. ‘Some adjustment must be made in the comparison of the two bins to compensate for the loss of storage associated with 53 the hopper system. The mechanical unloader may be either a permanent fixture in one bin, or a portable device for use in a number of similar structures. The hopper is a perman- ent installation. Selecting the handling method. The question of whether to use mechanical unloading from ground level bins or gravity unloading from elevated structures is primarily one of cost. Whether to use a hopper-bottom bin or a mechanical unloader in a flat-bottom bin is also a question of cost. Unfortunately, data on the cost of elevating and hoppering bins are markedly lacking. Similarly, mechanical bin un- loaders for flat-bottom structures are not manufactured to any great extent. Consequently, a detailed cost analysis is not possible at the present time. This does not mean that some general guides concerning the use of these materials handling methods cannot be for- mulated. The factors that influence decision making can be stated. A rigorous evaluation of most cost aspects of each method, however, must be left unanswered. The cost of grain storage unloading is a function of the type and amount of material handled and the handling frequency. If one bin is unloaded once per year, the cost of the handling method must be charged to that one quantity of material. In contrast, if one bin is unloaded and 54 refilled many times throughout a year, the cost of storage unloading can be charged to the total quantity handled. Cost per unit is proportionately reduced. Similarly, if one bin is completely unloaded in one operation per year, a single equipment set—up is involved. If, in contrast, some withdrawal of material is made every day, a compli- cated set-uplof equipment may involve more time than the actual operation. The handling cycle affects the choice of method in another way. If similar storages each contain the same kind of grain, only one storage need be opened at a time. When unloading is completed in one structure, a portable mechanical system may be moved to a second storage. In contrast, if material must be withdrawn from several bins in the same time period, moving the unloader tends to be impractical. Too, if both bins are not emptied at each withdrawal, moving a bottom unloading mechanical device is impractical. Handling system design guides. In planning feed- grain handling facilities, some general recommendations lSet-up as used throughout this text means the nec- essary arrangement, assembly, and servicing of equipment prior to operation, rather than the equipment itself. The latter is sometimes described as an equipment set-up, but the author does not use this context. 55 concerning the use of gravity and mechanical systems of handling can be formulated. These recommendations are: 1. Limit the use of elevated structures to small working bins in the processing area. The more times a bin is refilled, the less is the cost per unit of material handled. Since elevating equipment is necessary no matter what type of storage is used, build small elevated bins and invest in high capa- city refilling equipment. Consider free standing, small elevated bins that can be rearranged in the future. Limit hopper bottom structures to working bins in the processing area. Since material and labor are major items in the cost of such facilities, keep bin size small. Use simple one-way and two-way slope hoppers instead of more costly four-way designs. Cost is materially reduced. Flow character- istics may be improved. Consider the use of hopper floors of gentle slope, rather than the steep 60 to 75 degree slopes required by most ground feed materials. The latter bins occasionally bridge, requiring agitation. Thus, supervision is required. The gentle slope requires more agitation, but uses supervision man—power already at hand. Invest some of the reduced construction cost of the gentle slope unit in methods of easier agitation. One-way and two-way slope bins place the "bottleneck" at the side of the bin, making hand agitation more practical. For 100 per cent unloading of bulk grain storage, consider the use of mechanical devices that remove material from a flat floor. Plan a portable installation of the unloading system, so that the unit can be used in all storages. Recognize the advantage of center draw-off as opposed to a side outlet, both from a maximum gravity flow and balanced structure side-wall load view-point. Determine the quantity of grain that will not flow by gravity to the storage outlet. The handling of this quantity of grain is all that can be accom- plished witha.hopper or mechanical device. 56 Feed Mixing A general criteria on mix requirements. The question concerning how complete a mix is necessary for each class of livestock is important in considering mixing methods. Little specific information on this question is available. A general criteria can be reasoned in terms of animal intake. The greater the intake, the greater the chance that the animal will consume a random mixture of blended and un- blended material. .This means that the smaller the animal, either in terms of age or type, the more important is a thorough mix. Thus, baby animals and animals such as chickens require a more accurate mix than adult swine or cattle. The use of feed as a carrier for growth stimulants and medication has placed more rigorous measurement and blending requirements on livestock ration formulation. In addition to questions of possible toxicity resulting from an incomplete mix, the cost and returns of the additive when not properly distributed throughout the herd must be con- sidered. Wagon mixers. The advent of self-unloading feed wagons has introduced a new dimension in feed mixing methods. Although these wagons are commonly advertised as transit 57 mixers, few models exhibit design features characteristic of horizontal mixers. With the exception of a few models, the mixing accomplished in a self-unloading wagon generally consists of withdrawing material from the bottom of the load, and discharging the material back into the wagon. Only one-half load can be so mixed on many feed wagons, because the discharge spout will not permit loading to the far end of the box. Standpoint of this thesis. The systems outlined in this analysis are planned for either wagon mixing or the use of a stationary verticle mixer. In my opinion in working with farmer's, rationsfor swine, beef, and dairy cattle can be acceptably mixed in a self-unloading wagon. Poultry and baby animal rations should be blended in a conventional mixer. The mixing requirements for adding growth stimulants and medication to feed may change as new formulas are developed, and should be considered in terms of specific standards for each material. Grinding_Cycle There are two alternatives in planning the grinding cycle. One involves frequent, small batch operation, and the other weekly or semi-monthly large batch grinding. The question of which cycle to use is primarily one of set-up cost. l 3" ‘lll‘ . ll...lll III..II'II...l|lr . 1 58 ' frequent If a grinding system is always "ready to go,‘ small batch processing is a good alternative to a large batch system. Automatic operation is especially well suited to small batch operation. If set-up time is virtually eliminated, short time processing approaches the longer cycle systems in the efficient use of labor. Tractor grinding systems, which generally are not automatic in operation, involve more set—up time than electrical powered systems. Consequently, the grinding cycle generally will be longer for a manually supervised tractor powered system than for an automatic system. Some farms have a sufficient number of tractors to permit per- manent location of one power unit at the grinding site throughout much of the year. The set-up efficiency of such a system can be high. However, this may not be efficient use of tractor power, and may add to operation costs. Feed Distribution Cycle Processed feed storage may be planned in several ways. The storages may be located at the processing site, with the feed distributed as needed. Or, the feed may be stored at each livestock area, either in an intermediate storage or in a self-feeder. The feed processing cycle and distribution cycle each influence the amount and location of processed feed storage. A short, frequent schedule of 59 both tends to minimize the amount of the storage space nec- essary. The greater the cycle length of either operation, the greater the storage requirement. In the author's experience in consulting with farmers, a few individuals have organized a feed processing and dis- tribution cycle to match the size of their self-unloading feed wagon. Feed is processed and discharged directly into the self unloading wagon. The cycle is planned on a day by day schedule, according to livestock needs. Each batch is stored on wheels, from which it is delivered directly to the feed area. One swine farmer delivers feed to hogs on pasture as he goes to and from field work. His only serious problem with such daily distribution occurs during an extended rainy period. Presentation and Discussion of System Layouts The Basic Plan The grain-feed handling system layouts consist of three basic components. These include: 1. A corn storage component. 2. A small grain storage component. 3. A feed processing and storage component. Figure l is a schematic drawing of the basic layout. Each unit is made up of ground level structures. This 60 .Acaaaomc oouapass m oucfi UoCHQEoo mucocoasoo Hm>oa unponw mo a: come ma pSOmmH comm .psomma Empmhm msHHUQmQ commucfimnw canon och mo wcfizmpc caumEocom ¢ .H csswfim pass on mm mafiaocmm mmeOBm can: pass E m ll w: moon I as + . + pooMICHmno mam Choc owmpopm comm 61 permits construction of any component at any time, inde- pendent of the remaining units. The only requirement in construction by components is an over-all plan outlining the final system. Construction need not be spread over a period of time, if a complete facility is desired imme- diately. Many options exist in the type of structures that may be used in building any component. Figure 2 is a schematic diagram of the component structures that are considered in this analysis. In the author's opinion, the structures listed in Figure 2 and outlined subsequently in more detail indicate building types and grain handling methods most representative of the needs of today's and tomorrow's agriculture. Some of the structures listed are not typically found on Michigan farms. This should not be interpreted to mean they do not represent sound investments. It Should rather be interpreted as a ques- tion concerning whether traditional designs are meeting the needs of today. New building designs offer features in storage methods and handling practices not even con— sidered in the planning of more traditional plans. The mechanization of materials handling is an im- portant consideration in the selection of any building. A structure planned in a period when a day's labor was EAR CORN DRY SHELLED CORN HIGH MOISTURE SHELLED CORN 62 CORN STORAGE SMALL GRAIN STORAGE Single C ib Drying Crib ‘Rmmd Crib .Round Bins Flat 2 Storage r4 Sack Flat 52) Supl. >. Storage .4 . .4 4—— -—— P/ :1 Lil - , - E: / a: Wood I w Round s. PROCESSING Bins , Bins E /a a: <: Flat Storage DISTRIBUTION Figure 2. Options in grain-storage structures and their relation to a grain-feed handling system. 63 worth 50¢ to $1.00 is a liability in light of mechanical handling possibilities today. Figure 3 lists in schematic form some of the mechanical handling methods that are available for storage-unloading, grain assembly and processing, and feed distribution. As with the storage components, the handling equipment may be installed as a complete assembly, or purchased unit by unit over a period of years. However, the necessity for a complete plan prior to the construction or purchase of any component is appar- ent. AS the reader reviews the feed-grain handling system layouts presented on the following pages, he will recog- nize a level of materials handling mechanization consid- erably above that commonly found on livestock farms. It should be remembered that this is one of the objectives of this analysis-~to present systems that embody a maximum opportunity for mechanical handling. It should also be recognized that there are many degrees of mechanical handling. Virtually all of these degrees are possible in the following layouts, from scoop shovel methods to maximum mechanical methods. In the author's opinion, no matter what level of mechanization is used, the layouts present an efficiency opportunity at least comparable to more traditional methods. 64 :chhw m mo coauocSM some now .Emanonm mafiacsmn boom noacaaasamnod meanness mementos: .m madman HmOHnoEEoo spam mmo Loam> Can nmaaom Icoo HHOHcmcomE Eonmdo somm> mozo> moNHE Icoo oohpunoz Icoo cameSOcm unoccfisc popcoacs ch OHOHBO> capuomam nomc>coo nomm>s00 sonom mcficmOHGSumamm HHHELOeEmm OHOHBO> dooom gouache OHOHBO> cop umfim Hafiz sham poxmmp no gomm wasp samzo nonm>oam gown no poxmmm nopomna Hc>onm accom Ho>onm Qooom Ho>onm mooom Emma so wcficmoacb wcfiomoq ZOHBDmHmBmHQ wqmzmmm< mwOHO mammppoa mo p:mEm>oE on» wsammm pom pmapnmo amonnm>o wcchHzm < xomsp nofinnmo mamas cannon m ma phone Eouponunsoon wcchfism .: opswfim 67 greatly simplified. The use of the conveyor in servicing a number of structures arranged around an enclosed area can be fast and efficient. Figure 5 is a schematic drawing of a one-way slope, wood hopper bin. The bin is rectangular in shape, with all floor stringers, flooring, studs, and sidewall essen- tially rectangular components. Fabrication of a hopper bin is thereby simplified. The bin is not designed to be entirely free-flowing. It is rather designed to operate with hand agitation, but with agitation that does not require much effort. The bin can be divided into any number of sections, each dis- charging through a flow control at the lower end of the sloping floor. The sections may be of any Size corre- sponding to needs. Partitions could be made removable, within structural limits, to permit adjustment of bin size to seasonal and yearly changes. An access door at waist to shoulder height is provided in each section for agi- tation of the final material reposing on the floor. Several options exist in mechanizing the material movement from the one-way Slope hopper bin. The bin may be elevated to discharge above feed cart height. Or, the discharge may be placed near the floor, with the material elevated with a mechanical device. The latter method 8 :0 .CH9 Eouuonunoaaoz macaw zmzncco a mo wcfizmnn unanswzom .m onswfim pooaom nomo>coo zonom _ _ _ sohcocfiw< pom whooo_mmooo< \ com ocean Hocccoo 69 requires a continuous hopper along the bin discharge. The use of a suspended screw conveyor system such as outlined in Figure 4 would permit servicing a long bin with one conveyor. A horizontal screw conveyor may be installed along the entire bin front. The use of left and right hand helicoids on one shaft will bring material to a central point. A permanent or portable inclined conveyor is used to lift the material to the desired height. Some caution must be used in the selection of the continuous horizontal conveyor system. Feed materials cannot be stored in adjacent bins on one conveyor train if any residual material remaining in the conveyor is objectionable in the other feeds. Too, if accurate weights out of storage are a part of the operation, it should be recognized that considerable material may be in transit when the final weight is reached. Provision for returning any overrun to the proper bin must be considered. 1 Ear Corn-Shelled Grain Layputs Single crib with circular metal Shelled grain. Figure 6 is a feed—grain handling system plan for a small lShelled grain includes both shelled corn and small grain. Many farms store some shelled corn. Since the storage structures for shelled corn and small grain may be the same. they are grouped under shelled grain storage bins. 7O 14' Die. ' 20' r] Layout 6a [Sca1e: 1/10" = 1'] A '=-_T—_——=I=l==——T_ ("—7 Elevation 6 :: - Sac‘ -1 Good- One-way slope ulk Bins I.‘ Hopper Bin oose-neck drag Bulk Supple. ‘—J Mill -J / Layout 6b Layout 60 Figure 6. Grain-feed handling system with a six foot wide single crib, two shelled grain bins, and a 20' x 24‘ processing area. 71 livestock farm. The plan features a 6 foot conventional or pole single crib for ear corn storage, coupled with round metal bins for shelled grain storage. One or both of the round bins may be equipped for in-storage drying. The primary difference in the three layouts of Figure 6 involves the location of the grinder. Layouts 6a and 6b use a stationary mill location, while Layout 6c requires moving the mill. In Layouts 6a and 6b, the ear corn conveyor system consists of a horizontal chain con- veyor placed along the side of the crib, and an inclined chain conveyor that feeds the mill. Both units are inde— pendently powered, although the inclined unit may be driven from the mill. The horizontal conveyor can be shifted to service either end of the crib. Layout 6b indicates a small hopper storage bin for small grain located over the grinder conveyor intake. This bin has a 2-way slope hopper, and discharges approximately 2 feet above floor level. This permits maximum capacity with the least height. The bin would be sized for one batch of feed. Layout 6c presents an interesting variation in ear corn handling mechanization. By running the drag tunnels across the crib rather than along the side, the amount of conveyor necessary is reduced. In the particular crib shown, running the tunnel across the crib will remove the 72 same amount of material by gravity as will a lengthwise installation running along the side of the crib, as in 6a or 6b. Since one conveyor with an inclined section at the discharge end is used instead of two tandom units, the cost of drive equipment is reduced. The cross tunnel method on a wood floored crib is also more easily in- stalled than a lengthwise tunnel centered in the floor, because the cross tunnel can be boxed in between floor stringers. The use of Shallow hoppers formed in the concrete floor is recommended at the intake of the grinder conveyor and in front of each round bin. Cast-in-place hoppers are out of the way, and in addition give the necessary height differential needed for tandem operation of two conveyors. The author considers the layouts illustrated in Figure 6 to be a minimum in space and capacity. The processing area is crowded. The driveway clearance is critical. The processing area can be expanded to 24 feet for additional space. Circular crib and circular Shelled grain. The layout in Figure 7 is very similar to that of Figure 6, except in the type of ear corn storage. Four additional feet have been added to the width of the processing area 73 111 Layout 7a. 24' x 24' Processing Area, Circular Wire Crib. [Scale: 1/10" = 1'] Elevation 7a Figure 7. Grain-feed handling system using circular ear corn storage with circular small grain storage. 74 to permit a wider door and driveway clearance. The round grain storage bins are Shown as equal size. ACtually, they may be made up of any combination of two bins that will fit the space and still give access from the proc- essing area. The reader will note this latter feature is a part of all layouts. In the author's opinion, a good grain-feed processing system permits batch assembly totally within an enclosed area. A layout that involves going outside in cold weather is poor design. In the layouts in Figure 7 (and all layouts in this thesis) the round structures are placed within 2 feet of adjacent buildings. This appears to the author to be a minimum distance to permit working between two buildings for construction or maintenance. If neither structure is round, this distance must be increased. The two round cribs in Layout 7a might be moved apart to bring the drag discharge nearer the corner. The power-take-off shaft length would be reduced, and some space gained for supplement and feed storage. The sack goods dock shown in Layout 7a is moved when the mill is moved. Assuming the corn storage is ample for a year's grinding needs, this involves one move per year. Layout 7b features a chain drag conveyor of the same type (a goose-neck drag--a horizontal drag with 7 < \Future \ 5 /"§995r b ‘\ ‘ S§ \\ Mill \\\ 1 \ '\§$§ / Inclined Screw \\\ -:::D \ ‘12 / \ ‘ Vi‘IGI‘. :E Goose-Nec Drag :LJFd.$ :Horizontal Elk: g screw 16' Dia sup- f ' Blk. h Sup. ? Layout 7b. 24' x 24' Processing Area, Circular Sheet Metal Crib. [Scale: l/lo" = 1'] Elevation 7b Figure 7. (Continued) 76 an inclined discharge section) as in 7a, but with a longer horizontal section. Layout 7b offers the advan- tage of a stationary mill location, along with the possi- bility of a hopper bin for feeding small grain into the mill. Although tractor power-take-off driven mills have been Shown in Figures 6 and 7, the use of belt driven mills for tractor or electric power is possible in all layouts. The reason for illustrating the power—take-off mill is to consider the location of the tractor. Since a tractor driving a power-take-off mill must be close to the grinder but clear of the driveway, this grinding method presents the greatest problem in planning. The use of round metal bins with a small crawl- type service hatch rather than a large walk-through door should be considered in each layout. When complete me- chanical unloading is used, the need to get inside the bin may occur only two or three times per year. The saving in bin cost when the walk—through door is elimi- nated can be used to partially off-set the cost of me- chanical unloading. Drying crib with circular shelled grain. The lay— outs in Figure 8 present some additional variations from previous plans. The primary difference again is the type A I . II p , {fol w G d. I :3 II we Fed ,3 ll 3'9 n‘ g, ! a) - It A I l ‘° is > . : . |'r'--—::=::: ' 4’ u' s 4. ' O ,o I. I Sack [<5 Ln " I '8 8 Elk (U \D 'I' g: .p I I. | q-l ((3 Sup. J ll I'S 8 0.] h. :1 l—‘l «1 ', Ira m L.‘ u |__.;. Layout 8a. 24' x 24' [Scale: 1/10" = 1'] -;i3 ““1"“ Screw Processing Area, Drying Crib. Figure 8. Elevation 8a 77 14' Dia. 16‘ Wide Grain-feed handling system using a 16' ’drying crib with circular shelled grain. 78 of corn crib used. The crib in Layouts 8a and 8b has a permanent drying tunnel running lengthwise through the center of the structure. This tunnel serves for drying, inspecting, and removing the corn. Whereas the crib in Layout 8a can be used with or without forced air drying, the additional width of the plan in Layout 8b must be equipped with a drying fan to satisfactory store corn in Michigan. The crib may be built in any length. The ear corn conveyor system in the layouts in Figure 8 consists of two separate units. One conveyor is inclined from the drying tunnel to the processing area. This unit is permanently installed, and may dis- charge at heights from floor level to the grinder hopper height. The second chain conveyor is a horizontal unit that may be shifted to either side of the drying tunnel, and to either end of the crib. Hence, the horizontal drag, which is one-half the crib length, can be used in four positions. Layout 8b indicates a small grain storage unit dif- ferent than shown previously. A four bin layout of round metal structures doubles the Shelled grain storage capa- city of previous systems. Any or all of the bins may be equipped for in-storage drying with either heated or un- heated air. One flat-bottom bin unloader can service all 79 .4 20' ‘ 10' 7:41; ._ + I] 14' Die. I . I “"""'1' | Mixer I Mill I A I Hopper Bin *———-——-— - Ground Feed. | I I I I | I i I 32‘—-3200 bu.-4Variable 100 bu/ft 1 1__! Layout 8b. 24' x 24' Processing Area, 24' Wide Drying Crib,Four Circular Grain Storages. [Scale: 1/10" = 1'] £14. Elevation 8b Figure 8.(Continued) 8O bins- The under—floor conveyor Channels in the two bins opposite the corn cirb in Layout 8O have been skewed in- ward toward the center of the processing layout. This places the discharge of the under—floor conveyor between the bulk bins. Cast-in-place hoppers are indicated between the bulk bins. The main service conveyor in the processing area is a 4 or 6 inch inclined screw conveyor, track~mounted as shown in Figure 4, Figure 9 outlines a plan that orients the crib used in Figure 8 in a different manner with respect to the processing area. Although the crib drag length is in— creased for this layout, the over-all plan is narrower than that of Figure 8. It may thus be adaptable where erection Space permits only a long, narrow facility. Any of the grinder and feed storage layouts that are planned for a stationary mill location, and one ear corn input, are adaptable to Layout 9. Thus, any of the processing area arrangements Shown in Layouts 6a, 6b, 7b, or 8a, are possible. In addition, the 4 bin Shelled grain component of Layout 8b, along with the corresponding grain processing area arrangement, is an option in Lay— out 9. The layouts shown in Figures 10 and 11 feature a tractor storage area as a part of the plan. The cribs shown are the same as those used in Figures 8 and 9. A 24‘ .41 16' 24' Layout 9 [Scale 1/10" = 1'] Elevation 9 Figure 9. Grain—feed handling system with 16‘ drying crib and circular shelled grain storage. Crib unloaded from one end. 82 16' [Scalez 1/10" = 1'] Elevation 10 Figure 10. Grain-feed handling system using two 16' wide drying cribs with circular shelled grain storage. 83 1 16' g _ O H b V a _I - 3’ I a) can. g I Feed | I I [Scalez 1/10" - 1'] Layout 11 Elevation 11 Figure 11. Grain-feed handling system using two 24‘ wide drying crib with four circular shelled grain storages. 84 comparison of Layouts 8a and 10 shows that the processing building in Layout 10 has been reduced in width. This is compensated by the space between the two crib storages. Figure 11 is a plan for a 4 bin shelled grain storage unit in conjunction with two drying cribs. Clear—span crib with circular small grain. Figure 12 presents a grain-feed handling system using a flat storage structure for ear corn. Layout 12a is designed for storage unloading with a tractor manure loader equipped with a snow scoop. The plan features two options in ear corn grinding. In one method (shown on the plan) a small hopper bin located in one corner of the ear corn storage holds sufficient ear corn for one batch. The bin is filled prior to grinding. A second option (not illustrated), would involve the use of a Short goose-neck drag, with the horizontal section recessed into the crib floor. A 10 foot to 16 foot unit would suffice. The drag would be located at the same point as the hopper bin. In operation, the tractor scoop would be used to pile a mass of ear corn over the drag. The quantity of ear corn that would flow from this pile by gravity and agitation would constitute a batch. The tractor scoop may be used to shove the re- maining corn into the drag. 85 Hopper Binfifi _1 (ear corn) 4:5//, Grd. d Goose- ee neck drag s 32' x 40‘ ‘Eiii" I 5000 bu. Sack l Goods? ‘_J 1 Layout 12a. 20' x 32' Processing Area, Designed for Unloading With Tractor Scoop [Scalez l/lO": 1'] t= .. 4 Elevation 12a Figure 12. Grain-feed handling system using a clear span. ear corn crib and circular shelled grain storage. 86 The use of a tractor scoop for storage unloading re- quires a double door into the corn storage area. Layout 12a is planned with a double door in the end of the corn storage, and a corresponding entrance on the Opposite side of the processing area driveway. .This may be unnecessary and uneconomical. It is planned as an option because a flat-storage structure may be used for various purposes. Hence, when the storage in Layout 12a is partially or com- pletely unloaded, it may be used for machinery or fertilizer storage, provided access is possible. The door arrangement shown would accomplish this, as would an entrance in the side of crib structure. The 4 bin shelled grain storage component in con- junction with a.flattype ear corn storage is Shown in Lay- out l2b. A drag system of ear corn handling consisting of two drag tunnels and one drag is illustrated. Depending on the height of the flat storage structure, one or two drying ducts may be used. With two drying ducts, the ducts would be placed over the drag trenches. Figure 13 shows two flat-storage structures set end to end, with the processing storage in between. This plan has some disadvantages. One criticism is the limited space available for processing equipment and feed storage. The plan also gives little room for shelled grain storage 87 32' x )40‘ ~- _ 5000 bu. (‘\ goods ,_+< $ $ :Goose ~neck drag nun / \ r...— Mill / I \ / \.. Grd. ; Feed J 1 Layout 12b. 24' x 32' Processing Area, Drag System of Bar. Corn m Handling [Scale: 1/10“ = 1'] D Elevation 12b Figure 12 (Continued) 88 Wham Grd. Feed 32‘ X 40' 32' X 40' 5000 bu. 5000 bu. Layout 13. 22' x 32' Processing Area [Scalez 1/10" = 1'] T; H v 'r r 2 l. .. Elevation 13 Figure 13. Grain-feed handling system using two clear span cribs designed for tractor scoop handling. 89 location. The latter storage might be incorporated into a section of one of the flat storage structures. Layout 13 has one advantage over all other layouts presented to this point. Assuming all of the ear corn will be fed out in a year, one of the storages should be empty by late winter. This unit can then be utilized for other purposes until harvest time. Considering the possible need for fertilizer storage and machinery repair during the spring planting season, this may be a strong asset. Dry Shelled Corn-Small Grain Layouts Clear span shelled corn with circular small grain. The layouts using flat shelled grain storage are essen- tially the same as those for flat ear corn storage. In fact, this is one of the advantages of such construction-- the facilities can readily be converted from ear corn to shelled corn. The primary difference in a flat storage layout for shelled grain as opposed to ear corn is the handling system. Figure 14 presents a flat storage and round bin lay- out for dry shelled corn and small grain. A comparison of this plan with Layout 12a will demonstrate the similarity in design. The unloading system for the flat grain storage con- sists of a horizontal screw conveyor (open top) recessed — / ‘ —_ \ \ / ' // \\ Automatic .3 Flatvfibttom \ grinder-mixer u bi? 1 \ \ w/hopper bin un oade // \a Bucket Elev. \Eorizontal a / iBelt \ screw .\ / PolgOI Blk.Supple, \ / '\ \ / /,’<\ Horizontal —--- ' '\ \ screw Layout 16. 24' x 28' ///1F‘\\‘ .Processing Area [Scale: l/lO" = 1'] Top Conveyor Elevation 14 Figure 14, Grain-feed handling system for shelled corn and small grain designed for complete mechanical handling [11' illl III‘ ‘III l 3'. .II it 91 in the center of the floor. Cover boards over the trench control the load on the conveyor. A flat—bottom bin un— loader is used in conjunction with the horizontal screw to convey grain to the trench. When gravity flow to the trench ceases, the unloader is placed in operation. By moving the unloader pivot point along the conveyor trench, 100 per cent grain removal is possible. Elevation 14 is a partial cross section view of the complete conveyor system. A vertical bucket type elevator is used both for in-to-storage and out-of-storage handling. A belt-type horizontal conveyor is recessed into the drive- way floor. A 6 inch screw conveyor mounted along the peak of the flat structure distributes grain along the entire length. Spouts are run to the circular grain storages. The horizontal screw conveyor in the floor of the circular storage brings grain to the boot of the vertical elevator. A flat bottom bin unloader is used to attain 100 per cent grain removal from the round structures. A Space is allotted in Layout 14 for a heated air batch drying system. Grain can be spouted to the dryer, and returned by conveyor to the elevator boot. One of the circular storages could be used for heated air batch drying with the flat—bottom unloader to remove the grain. However, the capacity of such a system would appear 92 unsatisfactory for the volume of grain considered in this layout. The rather unorthodox appearance of the headhouse of the vertical elevator in Elevation 14 is necessary to attain spout height to the side structures. The use of a horizontal conveyor to carry grain to the side structures might be con- sidered an alternative method. Figure 15 presents a double flat storage layout and elevation. The processing area is centered between the two structures. The advantage of two flat storage units, one of which is unloaded by mid—winter, was discussed previously. It applies equally well in this layout. 8 The handling system in Layout 15 differs from 14 in several respects. First, the absence of the round struc- tures at the side reduces the need for the high headhouse. However, the batch drying bin has been moved to the side, and requires filling from the central elevator. A hori- zontal conveyor is substituted for the high headhouse. This conveyor conceivably can be the same unit used for storage unloading. Since both operations are not carried on at the same time, dual use is possible. The use of free—standing low outlet height hopper bins for wet grain storage is a part of the plan. They can be filled with either the vertical elevator or directly 93 -' \\ \\v Automatic Flat-bottom grinder~mixe 32: X you bin un~ \ W/hopn r bin 10,000 bu, loader'fik \ Bucket Elev. \ fl SCI'LEW I éBelt / 32' X 40' / 10,000 bu. / W=h grail /’ bl}; LJU Yjje ,/ __ / Layout 15. 24‘ X 32' Processing Area [Scale: 1/10" 2 1'] Dryer Ty} Conveyo track mounted Elevation 15 Figure 15. Feed-grain handling system featuring two clear span storages, drying, automatic grinding, and complete mechanical handling 94 from a self-unloading grain-feed wagon. The hopper stor- ages are positioned to discharge directly over the return conveyor from the drying bin. Hence, wet grain (and throughout the year, ground feed and supplement) can be returned to the vertical elevator boot for handling. The absence of bins for small grain storage is a criticism of Layout 15. These bins can be added in the flat storage adjacent to the elevator. The storage Layouts in either Figure 14 or 15 may be filled with portable outside elevators. However, the addition of drying to the handling requirements should suggest the use of a vertical bucket elevator. An automatic electrically powered grinder-mixer is featured in the Layouts of both Figures 14 and 15. The grinding systems consists of a four compartment hopper— bottom bin, the four channel grinder-mixer, and a 4 inch screw conveyor to deliver ground feed to a self-unloading feed wagon or a bulk storage bin. Circular shelled corn with circular small grain. Figure 16 presents a shelled corn and small grain layout consisting entirely of round storage structures. A ver- tical elevator serves as the central conveyor, and is fed with a horizontal belt conveyor recessed in the drive-way floor. With the elevator located in the center of the fl Wet corn or blk.sup1. :Belt 7‘ Dryer ‘—'1L 1 -_:_ Bucket Elev. Automatic grinder- mixer w/ hopper bin 18' Dia. 3000 bu. Layout 16. 24' X 28' 18' Dia. Processing Area Elevation 16 Grain-feed handling system with circular shelled corn storage, drying,automatic grinding, and complete mechanical handling. Figure 16. 96 bin circle, the horizontal drive-way drag must be longer than in Figures 14 and 15. The unorthodox headhouse appears again in Layout 16. The height is necessary to maintain slope on the spout tubes. Grain is also spouted to the drying system, although a mechanical conveyor in the top of the processing structure may be substituted for gravity spouts. A weather-proof vertical elevator installed outside the processing building is an alternative to the tall head— house. However, with so many spout lines involved, the author prefers the shelter of the enclosed headhouse to keep moisture out of the distributor head and vertical leg. The outside elevator would require support for stability. This can be done by cable guys, or by installing a utility pole on each side of the vertical leg. The tall headhouse would be framed around two utility poles. The out-of-storage handling system for Layout 16 is the same as that for the circular storage units in Layout 14. The use of grain aeration equipment in dry grain storages of over 2000 bushels capacity must be considered in storage layout. The round metal and flat storage struc- tures outlined in the previous dry shelled corn layouts are adaptable to either a floor-level or top mounted system. 97 The top mounted system offers the advantage of no obstruc- tions in storage unloading. Although common in circular storages, the use of an overhead suspended aeration system in flat storage would be considered experimental. High Moisture Corn-Shelled Grain Layouts The layouts for high moisture corn storage are almost identical in plan View to those for circular dry corn storage. Two alternatives in structure choice exist. These include silos and metal storages with plastic bag liners. Silo corn storage with circular shelled grain. A silo layout is shown in Figure 17. An outside weather- proof vertical elevator is illustrated, although a forage blower should be considered an alternative. Placing the elevator outside the processing area adds to the length requirements of the cross-driveway drag. The out-of- storage handling system is not materially affected by the shift in elevator location. The bulk of high moisture corn to date has been stored in hermetic (gas tight) storages. However, research underway indicates that non-hermetic storages may give sat- isfactory preservation. Consequently, non—hermetic storages can be considered as an alternative to gas-tight structures. 98 @/ 14' Dia _ - .QBelt [ Wet corn or blk.sup1e. Layout 17. 24' X 24' Processing Area [Scale: 1/10" = 1'] Elevation 17 Figure 17. Grain-feed handling system using high moisture corn storage and a vertical elevator. 99 Plastic—lined circular corn storage with circular small grain. Figure 18 presents a storage layout essentially the same view in plan view to that of Figures 16 and 17. The storage structures in Layout 18 are round metal bins with plastic bag liners. This storage method, developed by Isaacs (21), is hermetic. The handling equipment system in Layout fl18 is the same as the 4 bin layouts without a vertical elevator for in-to—storage handling. A vertical elevator system can be used, if desired. Unloading high moisture corn from flat-bottom bins is a problem with few answers. The glass lined hermetic storages are commonly sold with a horizontal screw con— veyor recessed in the floor. The intake of the conveyor is centered in the floor° This method of unloading can- not be safely applied to tall structures not designed for non-uniform sidewall loading. With one—point withdrawal, the grain may not feed uniformly to the conveyor. An un- balanced sidewall load may cause the structure to fail. The shallow depth metal bins of capacities less than 1000 bushels studied by Isaacs have been unloaded satisfactorily with a horizontal screw conveyor injected into the side of the grain mass. Farmers in Indiana have used plastic liners on bins over 1000 bushels in capacity. The use of top-mounted silo unloaders for high moisture corn unloading has not been investigated to any appre- ciable extent. 100 24' x 24' Layout 18. 24' x 24' Processing Area [Scale: 1/10" = 1'] Elevation 18 Figure 18. Grain-feed handling system using plastic- lined round metal bins. VI. PRESENTATION AND DISCUSSION OF COST AND CAPACITY DATA Cost As A Measure A measuring criteria of some dimension is needed as a foundation for the analysis and discussion of the grain- feed handling systems presented in the previous chapter. There are a number of system characteristics that might be measured, including total horsepower required, labor re- quired, the feet of conveyor used, the amount of buildings and building space used, et cetera. However, any one of these characteristics would give very little information about the total system. Each is a somewhat specialized measure that may or may not have any significant bearing on the over-all performance of the system. Each of the above system characteristics have at least one common denominator, namely cost. A cost analysis can simultaneously consider the floor space, horsepower, feet of conveyor, and labor. A cost analysis represents a total measure, to the extent that costs are indicative of the inter-relation of these and other system characteristics. Cost expressions are static in terms of time, having been derived for a particular product with a specific time, 101 102 place, and form relationship. This static characteristic of cost relationships presents some limitations in their use, because of the dynamic nature of reality. This does not mean that static cost estimates are not useful. They are probably the most valuable guide to decision making in use today. Farmers and farm managers must use such esti- mates almost daily to project management into dynamic sit— uations. Equipment Costs The cost data presented on the following pages were obtained from manufacturers and distributors of grain handling and processing equipment. In the author's opinion, these data represent typical price schedules for equipment available to Michigan farmers. The reader should recognize some of the assumptions that are made in the preparation of such a cost schedule. First, a choice must be made concerning which equipment to include in the listing. This presents an immediate problem in ascertaining service requirements of the equipment for the particular operation in mind. Too, special features on each device, boldly advertised as preferable to any other product on the market, must be credited or discounted on an arbitrary basis. lO3 The final price schedule is determined by an averaging process,1 using the equipment and price schedules considered representative of the situation. This average price can then only be used as a guide in consideration of a specific situation. It must not be considered as an absolute value. The author believes that his farm experience, coupled with nearly ten years of professional experience in working with materials handling equipment and problems on farms, adds credence to the validity of the equipment and cost schedules presented in this thesis. The equipment data are more accurate than the building data, because the equipment represents a more standardized product, subject to more accurate price determination. Too, since the equipment tends to be small, there are generally more manufacturers building such devices than farm building manufacturers. Consequently, more manufacturers are repre- sented in the equipment schedules than in building schedules. Grain handling equipment tends to be purchased as a complete package, ready to operate, whereas farm buildings are often built by the farmer. The latter is particularly true of wood, site constructed buildings. The descriptive- ness and accuracy of the price schedules on building are, lThe averaging process used in the development of cost schedules was of several forms. Given a number of devices, the cost schedule was determined by fitting a regression line using a least squares method. With two devices, the cost sch- edule is a simple average. With one device, the manufacturers price schedule was used. lO4 consequently, directly proportional to the degree of stan- dardization of each building type. The quotation on round metal bins can thereby be considered with much greater assur- ance of accuracy than the quotations on wood structures. Similarly, quotations on traditional wood structures, such as the single crib listing, can be used with greater assur- ance than the clear span crib estimate, since the latter represents a new plan from which few buildings have been built. Use of cost data. The author wishes to impress on the reader that the cost data presented on the following pages is intended as a guide. To attain greater accuracy, local prices should be used in estimating the cost of all components for an actual farm situation, Using these local prices, the procedure outlined in the cost analysis can be applied. Equipment Horsepower and Capacity Formulating the horsepower requirements and output capacities of materials handling equipment presents as great a paradox as that of cost schedules. Manufacturers quotations are extremely inconsistent. They are most con- sistent in the presentation of no data, or in the listing of data in ranges so broad as to be meaningless. Millier (31) presented a comprehensive study of screw conveyors. Graphic summaries of his findings are lO5 presented in Appendix A. Wiant and Sheldon (41) outlined the power requirements of bucket elevators for capacities up to 400 bushels per hour. McKenzie and Ross (30) present data on the power requirements of a flat-bottom bin unloader. Capacity and horsepower requirement data for the re- maining grain handling and processing equipment was deter- mined by rather subjective methods. This generally con- sisted of reviewing manufacturers' quotations, and equating these to actual situations in the author's experience. Since the power requirements of most conveying devices are linear, an established relationship documented by experience was used as a base value. Capacity figures are more diffi- cult to document from experience, because of the highly variable nature of grain materials, particularly ear corn. Manufacturers quotations, with adjustments based on the author's experience, were the final criteria used. Table III is a presentation of the estimated horse- power requirements and output capacity for selected grain handling and processing equipment. It should be noted that some devices have been divided into light duty and heavy duty classifications. 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The values used are those suggested in the Agricultural Engineers Yearbook (1). TABLE IV ASSUMED INTEREST, TAX, HOUSING, AND INSURANCE SCHEDULE FOR STRAIGHT LINE DEPRECIATION OF GRAIN HANDLING AND PROCESSING EQUIPMENT--PER CENT OF NEW COST PER YEAR1 Assumed Rate Fixed Cost Per Year Per Year Item Per Cent Formula2 Per Cent Interest 5.0 (P+S) i 2.75 2 Taxes 1.6 0.016P 1.6 Housing 1.0 0.01P 1.0 Insurance 0.4 0.004P 0.4 TOTAL 5.75 1Source: Agricultural Engineers Yearbook. 2Symbols: P is purchase price in dollars or per cent; S is salvage value in dollars or per cent; 1 is interest rate. A complete schedule of fixed cost relationships for grain handling and processing equipment is presented in l .1.» l . III'IIII' - 109 Table V. The life in years for all values not footnoted were estimated from Kleis (24) and the Agricultural Engineers Yearbook (l). Summaries of these basic data are located in Appendix B. The repair schedule was determined from these same sources. The value selected was that considered most applicable. The reader should note the difference in hours of life stated for light duty and heavy duty chain and auger con- veyors. There is no basis for this difference in references cited. The values reflect the authors' judgment. Equipment Cost Schedule Table VI presents fixed and variable cost relationships for grain conveying equipment. The values are presented in terms of two figures, one for the basic length unit and a second value to be added or subtracted for the module length change. With this method of presentation, any length of conveyor with the range specified in Table VI can be eval— uated on a cost basis. The fixed cost schedules in Table VI are presented without including the motor cost. This is necessary because electric motor costs are not linear with respect to horse- power. When a conveyor unit is selected and the costs deter- mined from Table VI, the motor fixed cost value is added to that of the conveyor. 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I. a I0 8 3 090 . B 2 WW an. e o a e 0... 2x6. 2 o 4 e: -um /o 03.8 .8002 00:: J O 8 J S U. J 00. J8 8 J S U. U. 38 U.I. SOT T. S a. 8 OT. SE S Q J QJ J0, EmpH a.rt a a e 0.rt .0 a a .La .L n YJJ e n J 9 n4. 3 . 8 1. . a. J yw Agouosvmasooz 0000000>< 0000 000002 0000Vu000 0000m j! Acmscfipzoov H> 00009 TABLE VI (Continued) SJBIIOG ‘nq OOOI Jed EGIQBIJEA SJBIIOflfi JBGA 880 898X10 T saettoq qsoo meN 1.25 0.13 1625 0.13 488a qqfiueq l 1 Basic Unit(Less Motor) Avaliable Module(&g%gr) SJBIIOG 'nq OOOI J80 geIQEIJPA SGIQEIJBA JBBA Je d EPGXTfi 10.75 1.60 saettoq qsoo meN 100 15.00 1880 uqSU81 qeeg eSueH UQSUGT 12 l I/QH Tun U91.OI Jed JemodasaoH tau/LI n8 Ithoedeo Item (With motor drive but less motor) I beam track Carrier—700# test Swinging boom w/ I beam track -D0ub1e angle track Overhead Carriers 116 117 The fixed cost values for electric motors are presented in Table VII. Note that fixed cost values are presented based on two different life estimates. This is based on the assumption that the life of an electric motor is equal to that of the device on which it is used. Although it may seem strange that an electric motor can have two lives, the author believes that a short life in grain handling equipment is associated with more rugged service. On this basis, the elec- tric motor would have a reduced life. Table VIII presents a fixed and variable cost schedule for selected grain processing and conditioning equipment. Since the devices listed are generally fixed in size and hence, horsepower requirements, the motor cost is included in the cost schedules. Storage Cost Schedule Table IX lists the estimated life, repair, and annual ownership values for grain storage structures. The life estimate values are slightly different than those often quoted. Wood grain storage structures are frequently listed with a 30-35 year life. Euler (10) lists a conventional double crib as 33 years, while placing the life of a metal structure at 25 years. This seems unrealistic to the author, first because the metal structure should remain in sound repair as long as a wood unit, and second, because obsolesence may void both structures before they are worn out. 118 TABLE VII ESTIMATED NEW AND FIXED COSTS FOR SINGLE PHASE REPULSION-INDUCTION ELECTRIC MOTORS AND MANUAL AND AUTOMATIC MOTOR CONTROLS Control Cost $ Total Fixed Cost/Yr.$l Horsepower New Auto- Cost 15 Year 12 Year Rating Cost $ Manual matic $ Life Life 1/2 78.00 17 95.00 12.11 13.53 35 113.00 14.41 16.10 3/4 96.00 17 113.00 14.41 16.10 35 131.00 16.70 18 67 1 103.00 17 120.00 15.30 17.10 35 138 00 17.60 19.67 1-1/2 139.00 17 156.00 19.89 22.23 35 174.00 22.19 24.80 2 181.00 21 202.00 25.76 28.79 39 220.00 28.05 31.35 3 242.00 21 263.00 33.53 37.48 41 283.00 36.08 40.33 5 309 00 25 334.00 42.59 47.60 41 350.00 44.63 49.88 7-1/2 511.00 25 536.00 68.34 76.38 75 586 00 74.72 83.51 lFixed costs computed using: Repairs-—2.0%; Interest-- 5%; Taxes—-l.6%; Insurance 0.4%; Housing-—None, Total: 15 yr. life--12.75%; 12 yr. 1ife--14.25%. TABLE VIII 119 ESTIMATED FIXED AND VARIABLE COSTS (EXCLUDING LABOR) 0F SELECTED GRAIN PROCESSING AND CONDITIONING EQUIPMENT. MOTOR AND CONTROL COST INCLUDED Cost-Dollars Capac- Item ity Horsepower Fixed2 Variable #/hr Requiredl New Per Per _, Year Ton3 Feed Grinders Hammermill-lO" 3500 10-25 237 37.32 0.63/T w/blower,wagon (tractor) spout,be1t pulley PTO drive-add 175.00 27.56 Trailer mtd-add 75 11.81 Burrmill-12" 3500 10-25 506 87.28 0.63/T' vertica1,station- (tractor) ary, flat belt drive, no elevator Accessories 9'e1evator-add 60 10.35 l'elevator sec- tion—add 7 1.21 PTO drive 30.00 5.18 6 groove "v"sheave 20.00 3.45 4' horizontal dis- 50.00 8.63 charge auger 8' single chain 190.00 32.78 mill—driven feeder Grinder—mixer 1200 2 645.00 95.14 0.066/T Gravity fed unit complete screens, automatic controls, auger base 1See Table III 2See Table V 3Tractor cost based on $1.10 1-hr, electric motors at 1 hp-hr = 1 kw-hr = 2¢. TABLE VIII (Continued 120 Cost-Dollars Capac- , Item ity Horsepowe Fixeda Variable3 #/hr Required New Per Per Year Ton Accessories Control hopper 374.00 55.17 for feeding from ground level, com- plete with power chords safety switches,auger base, bin level switches, wall switch panel. Safety switches-- 4 channel 11.25 1.66 Corn Sheller-Station- 125 7-1/2 290 39.88 -l.lO/hr ary cylinder-type w/ bu/hr elec. flat belt drive, 9' 10-15, cob stacker,corn tractor blower & wagon spout Accessories PTO drive 65 8.94 Trailer mounting 100 13.75 Feed Mixers-Vertical type complete w/ 1 bagger, access hatch, 2 sight windows,"v" belt drive(top) less motor 700# above floor 3000# l 406 55.83 0.013 hopper 1200# above floor 4000 2 605 83.19 0.02 _ hopper 2000# floor hopper 5000 3 801 110.14 0.024 3000# floor hopper 6000 5 1053 144.79 0.033 Drying Fans-Ear Corn 6 blade direct con- nected-— 32" 2500bu 3 520 61.20 0.023/bu 36" 4000bu 5 780 91.70 0.023/bu 42" 6000 7-1/2 1060 124.50 0.023/bu 121 TABLE VIII (Continued) Cost-Dollars Capac- FixedE’Variable5 Item ity Horsepower New Per Per #/h4 Requiredl Year Ton Aeration Systems Top mounted unit 3000bu 75 8.80 0.005/bu w/6' perforated pipe, motor,fan Aeration Fans l8"-7 blade semi- 1/2 235 27.60 0.005/bu pressure direct connected fan, motor , l8"-7 blade as 1-1/2 360 42.30 0.005/bu above Aeration Duct—Metal l sq.ft.cross- 4/ft 0.44 section .meaa names An ebba>ae nooa pa coapnae nopdoo mSHQ .&N am mmxme «RH 98 mocmLSmcH .Rm pm pmmpmch mafia whamamp moodaocH Hmpoefi 122 mo.o-ofi.o m.ma o.m oo.o-om.o ooomnooo: mm mm ooomoH npabe .oa .meaz.qm -ooo aa.o-ma.o m.ma o.m mw.o-oo.a ooam-ooom mm mm 0060 mnane .o .mbaz .ma -ooom .wcannaao and: emeamz nuaz mamunmaoo pamoxm m>onm mm mean swam bean babe--paao manzom ca.o-ma.o m.ma o.m om.onoo.a ooomuooom mm mm ooomoH nnaao_oa.mcaz.em -ooo ma.o!ma.o m.ma o.m mo.H-mm.H commuoomm mm mm oooo agape .m.mba3_oa -ooom .Hmscsn wean AHOCQSD weahpouzmzxamz coaumcHnEoo_mx.znnzmz IO>HLU on Hmcofiucm>coo unnauo Cannon ma.o:ma.o m.mH o.m oo.Huom.H ooomuomoH mm ma ooom .o Oahu maom ICON Innfiho mawcfim wa.o-am.o m.ma o.m om.H-oe.H oomm-omaa mm ma ooom cpeHz_m Hacoapcm>coo noon --paao mawnam H "v .3 a $33. manna Hannsm Lem Seem. ms md OH 3. 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T8 3...... 3 G. e e u. n ‘ a o 30000300000 33 00039 The estimated annual repair values were GEJCIODOU uSin; Euler (10) and Wooley (MA) as a guide. The interest, tax, and insurance schedule is footnoted on Table IX The total fixed cost values of Table IX are presented in terms of annual cost per bushel of storage. Thus, a direct comparison of estimated storage costs for each structure is possible VII. .COST ANALYSIS AND DISCUSSION An Evaluative Framework Analyzing#$ystem Costs The costs of owning and operating the grain-feed hand- ling systems presented in Section V can be analyzed from several View points. The primary consideration is the effect of through-put volume on unit handling costs. The through- put volume can be varied in two ways: (I) The system size (storage capacity) can be increased to handle a progressively larger volume of material; and (2) the system size can be held constant with the through-put variable, A discussion of these alternatives analyses and their effect on cost relation— ships is presented below. _Variable through—put——variable system size. Increasing the amount of storage to handle additional grain produced and fed is not unusual on many Michigan livestock farms. The grain may either be farm produced or purchased at harvest. In either event, the feed grain handling facilities are designed to hold a year's supply of feed. In analyzing costs, increasing the grain volume handled by increasing the system size presents a changing fixed cost° 128 129 A given fixed cost is characteristic of a particular system; change the system, and the fixed cost will change. The equipment components may also be altered, as the through-put of material is varied. Increasing the storage size entails some combination of increases in length, width, height, and diameter. Additional equipment length and/or capacity necessary to service this increased structure size adds to the system fixed cost. Modifications in the length or capacity of handling devices alter power requirements and thereby affect operating (variable) costs. A discussion of the relationship between system grain storage size and equipment capacity is considered in a sub- sequent discussion. Variable through-put—-constant system size. Two types of grain-feed storage programs on farms operate by varying the amount of material handled through a given size facility. One is the farm operation that purchases feed grain through- out the year. The other is a farm enterprise with several storage locations on separate farmsteads, but with a central— ized livestock operation. This latter enterprise organization deserves some dis- cussion. The growth in livestock and crop enterprise volume has generally been associated with purchase of additional land (38). But these land purchases are often located some 130 distance from the headquarters farmstead. This distance pre- sents problems in crop and livestock enterprise organization, Just as it does in grain-feed handling system design. Two considerations are important to the discussion at hand. Long hauling distances during grain harvest reduce harvest speed, thereby increasing the risk of field loss due to weather damage. The location of grain storage at or near the crop production site contributes to expedient harvest. Increases in livestock enterprise volume and efficiency, on the other hand, usually are associated with more production per man-hour (Table I). This generally means a more concen- trated operation, so that the enterprise can be more effici- ently serviced and supervised. Thus, while the farm acreage tends to spread out as the enterprise volume is increased, the livestock enterprise organization tends toward central- ization. A logical answer, from the standpoint of grain-feed handling system design, is to construct an efficient storage and processing center at the livestock enterprise site. This facility is sized in terms of the grain production on the adjacent land and the efficient transfer of grain from outlying storage points. The fixed costs of the central facility are constant, and as the volume of material handled increases, the fixed cost per unit decreases. Variable costs are constant for each unit of material handled, up to the 131 point at which equipment use exceeds the service factor for which it was designed. System comparisons. The results of either analysis dis- cussed above may be combined in a comparison of different systems operated under the same circumstances. Assuming that the systems are comparable in performance, conclusions based on comparative costs can be drawn. Other Considerations Equipment and storage capacity. Handling and processing equipment capacity is generally sized in relation to live- stock enterprise needs. The effect of the grinding cycle on the choice of processing equipment was discussed previously in Section V. Ideally, processing equipment might be sized to grind a day's feed supply in 24 hours. With automatic equip- ment, something approaching this ideal design may actually be practical, although some allowance must be made for service and break-downs. In reality, a grinding cycle of less than 8 hours per day is desirable, In fact, the grinding cycle on a manually supervised operation must be sized in terms of the seasonal demands on labor. Spring planting is probably the most critical period, The marginal valueproductivity of labor in grinding feed must be compared to the marginal value pro- ductivity of labor for producing crops (or for any other 132 competing enterprises) because this is what the labor would earn if invested in the other enterprises. Unfortunately, information and methods that will permit an expedient evaluation of the marginal value productivity of labor in such circumstances is unavailable. Consequently, an arbitrary basis for analysis must be established. It seems reasonable to the author that a grain processing system requiring manual supervision should have a capacity sufficient to process a one week supply of feed in one-half day. This arbitrary standard is based on the spring season as the critical period, and the assumption that inclement weather will occur at least once within the week. To plan to grind all day would disregard other competing rainy day activ- ities, such as machinery repair, purchase of supplies, or leisure. To set a standard that allotted less time to grinding would appear unrealistic in terms of available equipment capacity. Placing a time limit on any operation involving equip- ment presents a critical problem in estimating equipment capacity. If the capacity of a given device is under- estimated, the unit is unduly discounted. The author wishes to emphasize again that the entire evaluation procedure based on costs and capacity data presented in this thesis should be viewed as a guide, rather than as an absolute measure. 133 Eabgr. In the presentation of all cost data in Section VI, labor was not included as a variable cost. This method of presentation was used to permit consideration of any equipment component as an automatic or manually supervised device. Too, man—power may be used to supervise several simultaneous devices, provided they are sufficiently close together that all may be observed and managed. Thus, labor requirements can be summed for any equipment combination used under several systems of operation. The set-up and knock-down time associated with different grain—feed handling systems, however, cannot be estimated with any assurance of accuracy. The time required to move a flat— bottom bin unloader from one bin to another once per year is probably insignificant in terms of total system cost. But the time requires to move a 4 inch diameter screw conveyor from one bin to another on an everyday basis may be highly significant. The author chooses not to attempt to estimate set-up and knock-down times for various and sundry grain handling equipment. To do so would be drawing on judgment with little credence or faith. The reader should recognize, however, that differences are apparent in the time required to get ready to do a job and to restore the original arrangement. These dif— ferences may be highly significant, particularly when auto— matic and manually supervised operations are equated. 134 Alternative equipment use. Some of the equipment in- cluded in this analysis can be used with other materials not connected with grain-feed handling. A double chain ear corn- baled hay elevator and a forage blower are examples. The system cost curves are developed assuming no alternative use. Alternative building use. In the discussion of system layouts in Section V, the use of clear span structures for activities other than grain storage was mentioned. Suggested activities included machinery repair, fertilizer storage, machinery storage, et cetera. To measure this additional-use opportunity of clear span structures, however, presents a problem very similar to that involving the use of labor. The value of the additional-use opportunity of a clear span structure depends on the need for the space. If the structure is needed for re-storing corn from less efficient structures, the value of the space is the marginal value productivity of the structure in storing another bushel of corn. This value must be equated to the MVP of the structure in storing ferti— lizer or machinery. Assuming no more corn is to be stored, the additional-use value of the crib is the MVP of the struc- ture in storing an alternative product. In the final analysis, ear corn storage in a clear span structure may be more economical than some other method, This does not say that the flexibility of the open structure should 135 not be added credit in its favor. Neither can one arbitrarily say that because an open crib is used only one-half year as an ear corn storage, then only one-half of its cost need be charged to corn storage. Livestock-~feed-grain relationships. One of the basic assumptions stated in Section V concerning the scope of this analysis limits the study to livestock grain-feed supplies. This means that the grain storage capacity of a given system must be planned to include a ratio of corn to shelled grain storage space in line with ration requirements. Agricultural Extension and Experiment Station personnel were contacted for information on livestock rations. General rations sufficient for estimating storage and processing re- quirements were obtained and are presented in Table X. The storage capacity ratio of corn to oats in each grain-feed handling system can be estimated from Table X. The oats component of each ration is between 20 and 35 per cent by weight of the corn component. Selecting a l to A oats-corn ratio as reasonably representative of all rations, one can convert the values to bushels and use them in estab- lishing system storage capacity ratios. The l to A oats- corn ratio is approximately equal to 3 bushel of oats to 7 bushels of corn. This is the storage ratio, and can be applied to any system. 136 TABLE X GENERAL LIVESTOCK RATIONS FOR ESTIMATING GRAIN-FEED HANDLING SYSTEM STORAGE AND CAPACITY RELATIONSHIPS Pounds of Material Item Swine Dairy Beef Corn-Cob Meal 1200 1825 Corn 1400 Oats 300 400 Supplement 300 400 175 Total 2000 2000 2000 Ave. Daily Intake per Head 7 10 15 Total Feed Req'd. per 1 2 Head 800 3300 2000- 3000 Pounds grain Req'd. per Head 680 2600 1825— 2700 lAmount includes pro-rated charges for sow. 2Amount includes 60 day dry period at A#/head/day. The reader should be cautioned concerning the use of the rations in Table X. These are composite rations, con- sidered sufficient for use in estimating grain-feed handling system requirements. Good quality beef cattle might be fed more corn than that listed in Table X. Limiting corn in a silage feeding program would involve less material. In esti- mating for a specific situation, values based on the actual operation should be used. 137 System Cost Relationships The cost analysis presented on the following pages is not a complete treatment of the systems presented in Section V. Considering the number of systems outlined coupled with the possible variations within a given layout, a complete cost treatment of each system with variations would involve time and space in excess of their total contribution to this thesis. It is the principles behind the development of cost relationships that are important to this thesis. On this basis, handling systems and building and equipment compon- ents have been selected that serve to bring out these principles. Storage and Handling Systems Only grain storage and handling systems from the in- take of the in—to—storage elevator to the output at a common point of the out—of-storage handling system are con- sidered in the cost analysis. The reason is two-fold. First, the analysis of a specific feed processing system is of equal magnitude to that of the storage and handling systems. Secondly, the storage and handling systems can be treated independent of the method of processing used. Grain processing may be done either on or off the farm. In either event, grain must flow from storage to a.rentral 138 point (a vehicle for transport to mill, or a grinder). Whether the storage is unloaded with a scoop shovel or a bin unloader, the grain ultimately is blended into the same ration. The equipment system for handling a given combination of grains at a particular level of mechanization is, therefore, rather independent of the processing system used. The only situation in which the above statement may not apply is in continuous flow systems. In continuous flow, the flow rate is controlled by the processing rate. This may be completely different than the rate at which a batch may be assembled. This is of particular consequence in ear corn processing, since the latter does not flow well from batch bins. In the final analysis, however, reducing the flow in ear corn handling equipment to rates below 500 bushels per hour is usually done by controlling speed, rather than in selecting smaller capacity units. Small capacity devices (in the 75 to 250 bushel per hour range) are simply not available. Although the reduction in speed reduces the motor cost, this is offset by the cost of speed reduction. Fixed costs are essentially unchanged. Variable costs, however, are significantly changed when flow rates are reduced. The primary change occurs in the labor costs. Operating a system at one-half the normal 139 capacity will double the labor costs per unit. Since labor constitutes a large share of variable costs, the additional cost of labor with the reduced system capacity is highly significant. Capacity and cost data for processing equipment were presented in Section V, and can be used as a guide in esti- mating processing system costs. However, the consideration of different processing systems and their effect on total cost relationships is left for future analysis. Cost relationships—-Layout 8a. Tables XI through XIV present detailed cost data for Layout 8a equipped for batch assembly with no consideration of the method of processing. The data is presented for a system built around a 16 foot wide drying crib. Since the cribs are only 6 feet in width, they may be used with or without drying equipment. The small grain storage components considered are round metal bins. These bins are not equipped for drying, although aeration equipment is included as a cost in storages of 2000 bushels or more capacity. Table XI presents a cost schedule for the static com- ponents of Layout 8a using the 16 foot conventional drying crib. These static components are the units that do not change with volume, and are thereby the same, irrespective of the size of cribs and bins used. 140 TABLE XI COST RELATIONSHIPS FOR STATIC COMPONENTS OF LAYOUT 8a ADAPTED FOR BATCH ASSEMBLY WITH- OUT PROCESSING OR FEED STORAGE EOUIPMENT Variable Cost Fixed Cost Power Investment Per Year Dollars Item Size Dollars Dollars per lOOObu. Processing Bldg. 24'x24‘ 1240.00 167.00 Elevator-Single 8"x24' 411.20 57 54 0.048 chain aluminum— unmounted Screw conveyor— 6"x 16' 221.60 23.10 0 023 unmounted Screw drag 5'x 11' 145.80 18.96 0.024 Swinging boom 6' 65.00 6.98 carrier Total 2083.80 279.58 Table XII contains data for the components that vary with the volume of material handled. It also demonstrates the use of the building and equipment cost schedules pre- sented in Section VI. Table XIII presents a summary of the investment and fixed cost values for several system Sizes. Table XIV presents the total and average variable costs for Layout 8a. The equipment variable costs are simply the summation of the variable costs for components. However, the COST RELATIONSHIPS FOR VARIABLE SYSTEM COMPONENTS TABLE XII LAYOUT 8a ADAPTED FOR BATCH ASSEMBLY WITHOUT PROCESSING OR FEED STORAGE EQUIPMENT 141 x. m m :3 I U) cu $4 H ,0 42B L o m .04JL Storage cos 6 o¢>w.a couaoo Volume Egg 3389.8 .3888 Item Size Bu. Ton g Q g0 g: Q g 94% Drying Crib 16 x 32 2000 70 2500.00 312.00 Grain Bin- 14 x 8 800 13 512.00 59.00 round Drying Crib 16 x 48 3000 105 3600.00 450.00 Grain Bin 14 x 10 1300 21 580.00 67.00 Drying Crib 16 x 64 4000 140 4630.00 578.00 Grain Bin 18 x 8 1700 27 813 00 94.00 Drying Crib 16 x 96 6000 210 6300.00 788 00 Grain Bin 18 x 12 2500 40 [871 00] [100.00] Aeration [ 75.00] [ 8.80] 5.00 System Total—- 946 00 108 80 Elevatoramtd. Double chain l Basic unit 24' 397.00 58.55 0.048 4—4’modules 16' 145.00 21.40 0.032 Tilting 8' 125 00 18.45 0.0C8 feeder 1 I Motor 5.... 23.32.22 £2.62 Total 1001.00 151.00 0.088 Crib Drag—8" - Basic Unit 16' 150.00 20.60 0.027 Motor 3/4hp2 131 00 16.70 Total 28I700 —37.30 0.027 Basic unit 16' 150.00 20.60 0.027 l-8'modu1e 8' u2,5o 5.85 0.013 Motor 1-1/2hp2 17b 00 22 20 Total 360 50 48.65 0.04 Basic unit 16' 150.00 20.60 0.027 2-8'modules 16' 85.00 11.70 0.027 Motor 1-1/2hp2 174.00 22.20 Total ‘E09.OO 54.50 0.053 1Manual control. 2Automatic control. TABLE XII (Continued) 142 778’ x. :1 c>m o .0 Storage 43.52 0:333 Sumo Volume 335.2 8.2 23338 Item Size >Er-4 wow-4 «400.4 Bu. Ton E. 8 378 :3 9.; Basic unit 16' 150.00 20.60 0.027 448'modules 32' 170.00 23.40 0.054 Motor 3hp2 283.00 36.08 Total 603.00 80.08 0.081 Bin Unloader 6' 250.00 32.50 0.015 Motor 1/2hp2 113.00 14.41 Total 363.00 36.91 0.015 Bin Unloader 6' 250.00 32.50 0.015 2-1'modules 2‘ 2 20.00 2.60 0.005 Motor 3/4hp 131.00 16 70 Total 401.00 51.80 0 020 labor charges are two-fold: One charge is for equipment supervision time and the other is for shoveling time. The former is the time required to move a quantity of material by the lowest capacity unit in the conveyor train. The crib drag, for instance, has a theoretical capacity of 600 bushels per hour. But the single chain elevator into which it dis— charges has a capacity of 500 bushels per hour. Hence, the latter determines the flow rate and the man—hours required. The man-hours in shoveling are required to remove that ear corn which will not flow to the drag conveyor with agitation. The angle of repose (with agitation) is estimated 1'. Ill 1" INVESTMENT AND FIXED COST SUMMARY FOR LAYOUT 8a ADAPTED FOR BATCH ASSEMBLY WITHOUT PROCESSING OR FEED TABLE XIII STORAGE EQUIPMENT 143 Capacity Tons .1311: 1253 .1272 229?. Ear corn--bu. 2000 3000 4000 6000 Small grain--bu. 800 1300 1700 2500 Investment Cost--Dollars Fixed complement 2084.00 2084.00 2084.00 2084 00 Cribs 2500_00 3600.00 4630 00 6300 00 Bins 512 00 580 00 813 00 946 00 Elevator 1001 00 1001 00 1001.00 1001.00 Crib drags, un— 517.00 790 00 810.00 1004.00 loader Total 6740.00 7994.00 9338.00 11,334 00 Fixed Cost/Year—-Dollars Fixed complement 279.60 279.60 279.60 279.60 Cribs 312.00 450.00 578.00 788.00 Bins 59.00 67.00 94.00 108 80 Elevators 141 00 141.00 141.00 141.00 Crib drags,un— 84.20 95.55 106.30 131 88 loader Total 875.80 1033.15 1198.90 1449.30 Fixed Cost/Ton 10 55 8.20 7.18 5.80 TABLE XIV 144 VARIABLE COSTS FOR LAYOUT 8a ADAPTED FOR BATCH ASSEMBLY WITHOUT PROCESSING OR FEED STORAGE EQUIPMENT-~16 FOOT DRYING CRIB WITH NO DRYING EQUIPMENT Variable Costs-—D011ars Item 83 Ton 126 Ton 167 Ton 250 Ton Equipment Single chain elev. 0.096 0.146 0.192 0.228 Crib drag 0.054 .120 .224 .486 Double chain 0.246 .290 .403 .572 elev. 6" screw-inclined 0.018 .030 .039 .058 5" screw-bin2drag 0.019 .031 .410 .060 Bin unloader 0.003 .003 .01 .01 Total 0.436 .620 0.906 1.474 Labor Supervisigg equip. 12.25 17.40 25.00 36.50 Shoveling 3.80 5.70 7.60 11.80 Total 16.05 23.10 32.60 48.30 Sum of Totals 16.49 23.72 33.51 49.77 Per Ton 0.20 0.20 0.20 0.20 lSmall grain capacity based on 50% Of ear corn. 2Bin unloader only used on non-gravity flow quantity for center’discharge. 3Shoveling is for ear corn that will not flow to drag-- estimated to be that quantity reposing under a 450 line from the drag. minute (ear corn). that a man can both supervise and shovel. Man-time estimated at 2 bushels per Supervising time per ear corn drag system was deducted from shoveling time on the assumption 145 at 45 degrees.1 Data by Ross (35) indicates that a man can shovel 150# of small grain per minute. Considering ear corn as more difficult to shovel than small grain, the shoveling rate was assumed 2 bushels (140 lbs) per minute. However, since supervision labor is already at hand to operate the equipment and agitate the corn for gravity flow to the drag, this same labor is considered available for Shoveling. The supervision time for handling the non-flow quantity was, therefore, deducted from the shoveling time. The use of automatic motor controls on the conveyor system is considered necessary to permit supervision and shoveling at the same time. A control switch on an extension cord can be carried to any point in the crib,_permitting remote control The use of an automatic Shut—off switch at the discharge in case an over-flow occurs would enhance the system Incidentally, unless additional labor is used to remove the non—flow quantity of material, the system capacity will drop from 550 bushels per hour to 120 bushels per hour (rate of one man Shoveling ear corn). It is obvious that additional man-hours must be charged to removal of the non-flow quantity Tables XV through XVII present summary cost data for variations in the crib type and Size used in Layout 8a. The 1Actually ear corn does not have a specific angle of repose The author believes that an angle does exixt above which ear corn will flow with a minimum of manual agitation. Below this angle, the ear corn must be shoveled. This angle is assumed to be 45 degrees. 146 TABLE XV VARIABLE COSTS FOR LAYOUT 8a ADAPTED FOR BATCH-ASSEMBLY WITHOUT PROCESSING 0R FEED STORAGE EQUIPMENT---24 FOOT DRYING CRIB WITH DRYING EQUIPMENT COSTS INCLUDED Variable CostS--Dollars Item 134 Ton 202 Ton 268 Ton 403 Ton Equipmentl 74.34 121.83 162.57 243.63 Labor Supervising equip- 20.50 28.90 40.20 60.50 ment Shoveling2 10.15 15.20 19.45 30.35 Total 104.99 165.93 222.22 334.48 Per Ton 0.78 0.83 0.83 0.83 lIncludes unheated air ear corn drying costs estimated at 2.3¢/bu. (McKenzie, 29) and areation costs for small grain in storages 2000 bushels or more) of l/2g/bushel. 2See Table XIV for description. variable costs presented in Table XV include the charge for shoveling the non-flow quantity of material, However, this quantity is considerably greater in a 10 foot wide crib as opposed to a 6 foot width. Costs are proportionally increased. The variable costs in Table XV also include charges for drying the corn. The 10 foot crib width requires forced air drying. Hence, the cost of such equipment must be considered "HITV'EIH L J TABLE XVI 147 SUMMARY OF TOTAL INVESTMENT AND AVERAGE FIXED, VARIABLE AND TOTAL COSTS FOR LAYOUT 8a ADAPTED FOR BATCH ASSEMBLY WITHOUT PROCESSING OR FEED STORAGE EQUIPMENT Capacity-Tons (Small Grain & Ear Corn) Description 83 Ton 126 Ton 167 Ton 250 Ton Drying Crib-Size 16x32 16x48 16x64 16x96 l6'conventional Total investment 6740.00 7994.00 9338.00 11,334.00 Fixed cost/ton 10.55 8.20 7.18 5.80 Variable cost/ton 0.20 0.20 0.20 0.20 Total cost/ton 10.75 8.40 7.38 6.00 16‘ Pole Total investment 6240 00 7279.00 8369.00 10,096.00 Fixed cost/ton 9.78 7.48 6.46 5.17 Variable cost/ton 0.20 0.20 0.20 0.20 Total cost/ton 9.98 7.68 6.66 5.37 Description 134 Ton 202 Ton 268 Ton 403 Ton Drying Crib-size 24x32 24x48 24x64 24x96 24' conventional Total investment 8099.00 10,299.00 12,033.00 15,481.00 Fixed cost/tonl 7.82 6.58 5.70 4.70 Variable cost/ton 0.78 0.83 0.83 0.83 Total cost/ton 8.60 7.41 6.53 5.53 24' Pole Total investment1 7499.00 9329.00 10,763.00 13,561.00 Fixed cost/ton 7.26 5.92 5.11 4.24 Variable cost/ton 0.78 0.83 0 83 0.83 Total cost/ton 8.04 6.75 5.94 5.07 lIncludes unheated air drying equipment based on an approximate 1 fan horsepower per 800 bushels of ear C OI’I’l as a system cost, structure cost. 148 and the dryer operating cost a variable Table XVII is a summary of the crib and small grain bin sizes and capacities considered in Layout 8a. TABLE XVII DRYING CRIB AND GRAIN BIN SIZES AND CAPACITIES FOR COST RELATIONSHIPS DEVELOPED FOR LAYOUT 8a Capacity——Tons Storage 83 Ton 126 Ton 167 Ton 250 Ton Crib Size 16x32 16x48 16x64 16x96 Capacity bu. 2000 3000 4000 6000 Binl Size 14x8 14x10 18x8 18x12 Capacity bu. 800 1300 1700 2500 Storage 134 Ton 202 Ton 268 Ton 403 Ton Crib Size 24x32 24x48 24x64 24x96 Capacity bu. 3200 4800 6400 9600 Binl Size 14x12 18x10 18x14 2—l8x10 Capacity bu. 1350 2050 2740 4100 lRound metal-~figure is diameter x height. The capacity figures are the quantity necessary for the system, not the exact capacity of the bin. Figure 19 is a graphical presentation of average fixed, variable, and total costs at different levels of capacity for Layout 8a adapted for batch assembly. The variable costs Cost per ton-Dollars 149 l2 11 . \ . \ W/ 7 6 AFC ‘\<:::“~\\‘¥ 5 4 3 2 VC = MC 1 f O LN” 50 77 100 fit 150'1 200 250 Capacity--Tons/Yr (small grain-~ear corn) Figure 19. Average fixed, variable, and total cost curves for Layout 8a with 16-foot wide conventional construction drying crib without drying, processing, storage equipment. or feed 150 are so small that they seem almost insignificant. However, it should be remembered that in the short run, variable costs are the only costs considered. Over a longer period of time, modification in the system can materially change fixed costs, which must therefore be considered in long range decisions. From a theoretical view point, one would expect this total cost curve to decrease to a minimum point, and even- tually increase as additional volume is handled. The minimum point would be the volume that should be handled to attain the lowest average total cost. Minimum average total costs may extend over a wide volume range. With the assumptions and equipment limitations considered in this analysis, however, the minimum ATC volume is never attained. This analysis is based on a constant equipment capacity and an essentially linear horsepower and equipment cost- length relationship. Labor is also considered directly pro- portional to the volume of material handled. Actually, some of these assumptions are not true. The constant equipment capacity with changing length is generally sound. But a con- stant equipment cost-length ratio holds true only within specific limits. At the point at which a heavier built drag unit must be employed to compensate for the increased chain load of a longer drag, the fixed costs will increase. Horse- power requirements also may increase. 151 Labor, however, is probably the major cost that will force the ATC curve to increase. As the crib increases in length, the time to reach the point in the crib where corn is being removed increases. Consider an extreme case: If the crib were a mile long, the time to get to the service point and return would be highly significant. However, in this analysis, no consideration is given to set-up time. Hence, increased labor costs with increased storage length are not included. A second and probably more significant source of in— creased labor costs can be attributed to the opportunity cost of labor.1 As a progressively greater volume of material is handled, the time involved in handling encroaches on the time needed for other tasks. At the point at which the marginal value productivity of labor used in any other process is greater than the MVP of labor used for handling grain, the labor charge for handling grain must be the MVP of labor used in the other process. Hence, labor costs rise. Grain handling labor must henceforth be hired (an added cost) or the handling capacity increased (adding to system costs). Thus, in reality, each system cost will reach a minimum ATC point at some volume through—put. The lack of data lOpportunity cost is the value of a given input that could have been attained in producing one product when the input is actually being used in another production process. 152 for evaluating set-up and knock-down labor costs and the opportunity cost of labor, however, prevents an accurate presentation of such a system curve. Figure 20 presents average cost relationships for Lay- out 8a using a wide crib with drying equipment. Only batch aSsembly is considered. Average variable costs are higher than for the system presented in Figure 19, because of the cost of operating drying equipment coupled with the labor costs of shoveling the non—flow quantity from the 10 foot wide crib. Figure 21 presents four ATC curves for Layout 8a with different crib widths and types. The reader should be cau- tious in drawing conclusions from the intersection of two system curves. Ordinarily, this intersection point can be interpreted as the volume at which one should change systems. With very accurate cost data, this interpretation is sound. However, the differences in the system costs of Figure 21 are so small that an error due to the accuracy of estimating data could materially change the relationships. The drying costs included in the wide cribs presented in Figure 21 also distort the system cost relationships. Figure 22 presents both the wide and narrow conventional crib with a 3 per cent reduction in field loss credited to the wide crib equipped for drying. The same credit could be 153 .pnmsmfisvm mwmhoum boom so mcflmmmoopa on p59 unmEQHSUm meampo .nfipo mafihpo coaposppmcoo HMCOHQ Lam ompmoncs modaocfi mumoo an>C00 06H: uoomuzm :pHB mm udozmq pom mm>950 meo mwmgo>< mm: Ashoo mmmnncflmpw Hamsmv smmw\mcoeuumpfiowamo 0mm OOJ oom Omm OOm oma .om mesmem 3r OOH >.g W. OZ O><. U OH saettoq--uoq Jed qsoo 154 In . .cmcfiaocH pcmeaasvm mMQAOpm 600% so wcammmoopm oz .mumoo pamamddvm wcfihpo mUSHosfi manta: boom Adomnmucmse .COHpoSQumcoo page mo momma o3» and mnpofiz nape 03» you mm psohmq pom mm>LSo pmoo Hmpop owesm>< .Hm mmswam AQLOo_pmmunchpw Hamamv pmmw\m:oenuzuaomomo mm: 00: 0mm oom 0mm oom oma OOH ms 0 H m m page wsahpc : COHDOSHDmCOo mHOQ .#N 1|: _ i\\V m llllllltllllllllt nape madman m. coauoshpmcoo // ®HOQ .mJ 0 A .IIII. ano wcfihpo imv AIIHUJN v w .coauosnpmcoo Hmsoapcm>coo .zm ILWWJ/lr _ _ _ m _ _ _ _ IIK/ A II page wcfihno coauodmpmcoo Hmsofiucm>coo .OH JV . lJr 0H HH saettoq--uoq Jed 1309* 155 A.p:mEQHSUm omeOpm comm so mchmooopa pSOEUHB mm pdozqu .wcHzno Op 056 COHposo Imp mmOH UHoHO pom pHompo pcoo poo m a mo poomgm mcHzocm mtho wcHhho boom um 8cm OH pom mm>950 meo HapOp owmpm>< .mm osstm Assoc smonuchpw HHmeV h%\chennszoQOo mm cow, omm oom 0mm oom omH ooH Illly Assoc pmov mcfimso on 036 mmOH .AIIIII cameo ea ceaseseea em gee: empeemao QillrllllllHHMHWIIlll unano_wcH%so .zmllv .:- .llllll _omosHoGH pcoEQHSUo wchpv ufpflpo wctho COHposspmcoo HwCOHQmm>coo _:m.ll _ O _ _ Amy / i a _ _ ooosHocH unmEQHsvm mcflhso cananso wchpo COHuodsumsoo HmcoHuCo>coo .OH _ _ _ w _ OH HH 2800 Y .180 f} ’I’ SJBIIOG--UO. 156 applied to the narrow crib, provided corresponding equipment charges were added. With storage loss data for storages of different construction, the additional in-storage loss of one structure as opposed to another could also be considered. Cost relationships with fixed versus variable system .EIEE- Any of the previous systems for Layout 8a may be fixed at a given size, and unloaded and refilled to attain addi- tional through-put. Table XVIII lists cost relationships for the 83 ton capacity system with a conventionally constructed drying crib. The fixed, variable and total cost values are computed for four levels of through-put. TABLE XVIII INVESTMENT AND AVERAGE COSTS PER TON FOR LAYOUT 8a WITH A 16 FOOT BY 32 FOOT CONVENTIONAL CONSTRUCTION DRYING CRIB‘DPERATED AT VARIOUS GRAIN THROUGH-PUT LEVELS Capacity-—Tons Total 83T0“ 126Ton 167Ton 250Ton Dollars Dollars/T Dollars/T Dollars/T Dollars/T Investment 6740.00 813 00 535.00 403 00 270.00 Fixed COSt 875.80 10.55 6.95 5.24 3 50 Variable 16.49 0.20 0.20 0.20 0.20 Cost Total Cost 10.75 7.15 5.44 3.70 157 The average cost values are plotted in Figure 23, along with the average costs for the same system when size is varied to increase through-put. As would be expected, the fixed system gives lower average total and fixed cost. Variable costs are equal for both systems. These curves do not present a true picture from the standpoint of many farm situations. The only situation in which the fixed system curve is indicative of total farm grain handling costs is with an operation purchasing grain supplies throughout the year. In this case, the one grain handling facility is the only unit needed. On a farm with storages located on outlying farms, but with the fixed system of Figure 23 located at a central livestock feeding site, the cost of owning and using the outlying storages must be con— sidered in the total handling costs. The labor and equipment to move the grain to the central facility must also be in- cllmlad, Storing grain in outlying locations for subsequent movement to the central facilities presents problems in esti- mating total grain handling costs. Some of the handling equipment such as the in-to-storage elevator may be used on all storages, including both harvest and rehandling oper- ations. Hence, the equipment costs should be spread over the entire quantity of material handled. Cost per ton-Dollars 158 12 i ‘ 11 I l 10 V§§§\ Capacity varied by (:;varying system size 9 1 1V 1 . \ \ ATC 7 \ M1 6 1 \\ k 5 C;\\ —ATC Fixed system size ::>>\ a Q \<\ HFC \t 3 2 l [S:-\AVC=MC (both systems)-m 0 R»... Figure 23. 100 150 200 250 Through-put--Tons/Yr (small grain-- ear corn) Average cost relationshps for various levels of through-put for Layout 8a with a 16- foot conventionally con- structed drying crib. One system is fixed at 83 tons capacity, the other is variable in size-from 83 tons to 250 tons capacity. 159 On the other hand, if the grain had all been stored in one central facility, the elevator would handle the material only once. Although the total cost per bushel handled would be greatest for one handling, the total cost of grain handling with the elevator would be a minimum for the particular system, since variable costs are minimum. As pointed out in an earlier discussion, however, the location of storages on outlying acreage permits more expedi- ent. harvest than with a central facility. Labor requirements tend to be high at harvest time. If storages are located near crop production, transport time is reduced. Surplus labor during the winter season may then be used in moving the mat- erial to the central facility. Since the opportunity cost of labor in the winter is generally lower than at harvest time, labor charges for moving the material in the winter should be below labor for moving at harvest time. The equipment costs for mechanizing and grain movement from outlying storage sites may be below that of a central facility. The central facility used for rehandling material from outlying storages is smaller than for a centralized storage system. Drags, elevators, and screw conveyors may all be reduced in length. Some of these units may also be used in unloading the outlying storages. Moving suffici- ently large quantities of material in one time period to 160 justify the set-up and knock—down of labor saving devices is an important consideration in reducing posts. Other Cost Considerations Two questions revolve around the use of mechanical equip— ment. One question concerns the cost of mechanical versus hand methods, and the other involves the cost relationships between several devices performing the same task. Figure 24 indicates the quantity of material reposing on the floor of a circular flat-bottom bin after gravity removal through a centered floor outlet. This is the quantity of material that should be considered in estimating the value of a flat—bottom bin unloader. The drag conveyor that removes the material from the centered outlet on a ground level bin, in contrast, handles all of the material stored. Hence, the base quantities for the two devices are completely different. Figure 24 presents average total cost relationships for shoveling by hand versus mechanical handling with a flat- bottom bin unloader. Two labor costs are shown. On the basis of this comparison, the unloader cannot compete with the man at $1.25 per hour in the volume range shown. At $2.00 per hour for labor, however, the unloader cost per bushel is equal to the hand method when approximately 4000 bushels are handled. No set-up or knock—down costs are included in either method. 3000 --—— ~—‘w—~ 161 Based on Angle of repose of 270 and on 18" dia. center outlet d) E Q 2000 -—-— -~ «4 m E (D '31 (D 8 g 1000 —» - U) 5 (11 O O 10 2O 30 ; Diameter--feet Figure 24. Bushels remaining in circular bin after gravity removal through a center outlet in the bin floor. 50 “K 40 Man rate based on , 150#/min. H Machine—-6OO bu/hr. (1)30 n [0 ii ‘\\\\>\\_ p 20 3 Man-$2.00/hr. ( C) 10-———Man-$l.25/hr. ‘~——— . l O lOOO 2000 3000 4000 5000 Bushels/Year Figure 25. Cost per bushel in handling grain from circular storage by hand and with a 6-foot flat-bottom bin unloader. 162 Several conclusions can be drawn from the curves in Figure 25° The justification of mechanical handling methods is directly related to labor cost and availability. The time required for the man to shovel 5000 bushels at the rate of 160 bushels per hour may conflict with other time require- ments. This is the opportunity cost of labor. This is of particular consequence on one-man operations, wherein the oper- ator is manager, capitalist, and laborer. Time spent in pushing a dull scoop shovel instead of a sharp pencil may prove costly. His time as a manager is worth more than is justified in manual labor that can be mechanized. The justification of mechanical handling that removes drudgery and hard work is also of importance on fanns using family labor or operated by individuals with a cardiac condi- tion. The question of which of two devices to use for a given task can be approached on much the same basis as the unloader versus hand methods comparison of Figure 25. VIII. SUMMARY AND CONCLUSIONS Grain-feed handling On livestock farms can be divided into functions of: 1. Storage 2, Assembly 3. Processing 4. Distribution Each of these functions can be analyzed independently of the whole system, with options developed for each func- tion finally integrated into a particular system. The fundamentals of efficient grain-feed handling system design are the same irrespective of the level of oper- ation involved. The degree of mechanized handling that a given operation can justify, however, is a function of the scale of operation. The design fundamentals for feed-grain handling system include: 1. Minimize distance. Minimize set—up and knock-down time. Design for multiple use of equipment. Use man-time first totflflrflcand last for power. Process in batches. Use high capacity, manually supervised batch assembly. 163 164 6. Plan in an open—end manner for future growth and alternative action. In terms of feed—grain handling system design, man-time should be used first to think, second as a floating control device, third as an expediter, fourth as an agitator, and last as a producer of horsepower. This sequence in the use of man- time can be reversed and used as a guide in mechanizing any operation. The mechanization would proceed as follows: 1. Remove drudgery. 2. Mechanize all handling. 3. Apply simple on-off control. 4. Integrate the control system. 5. Introduce automatic programming. The grain-feed handling systems developed are consid- ered representative of the needs of Michigan livestock farms, both large and small. The systems presented tend toward large scale operations. This is in line with one of the ob- jectives: To develop systems that permit a maximum level of mechanization. It should be recognized that it is easier to reduce the scale and eliminate some features of a given system than to project a small system beyond limits consid- ered in its design. It should also be recognized that scale and mechanization go hand in hand. A small operation may afford little mechanized handling. 165 The system layouts present a plan for the future. The storage structures considered are representative of the most modern building types and storage practices available. The construction-by-components feature of the systems permits a gradual transition from an existing to a desired layout. Sound existing structures may become a part of the new faci- lity, or be relegated to a minimum re-investment status to permit expedient economical replacement. The systems use ground level structures for all bulk grain storage. This is essential to the construction—by- components feature, wherein each structure must be a unit. Elevated bins are limited to small working bins in the proc- essing area. These small elevated bins are generally free; standing units with hopper bottoms. Free-standing units permit rearrangement of the processing area, or organization of the processing facility in an existing building, to be moved at a later date to new facilities. The free-standing bins may also be owned by the tenant, thereby giving him more control over the feed handling facilities. The use of one-way hopper bins with a gentle slope that requires some agitation should be considered in place of four-way and circular hoppers with steep slopes. The sim- plicitycflTthe one-way slope bin reduces construction costs. Since bins with steep slopes occasionally bridge, supervision 166 during unloading is necessary. The gentle slope bin makes use of this supervision labor for agitation that requires little effort. Some of the reduced cost of one-way hoppers may be used in making agitation easier. Ground level storage structures used in conjunction with a grain elevating device are an alternative to gravity storage unloading from elevated bins. The grain elevator should remove grain from the same point in the bin, and deliver it at a rate and height comparable to the elevated structure. Whereas elevated construction for gravity flow involves a duplicate investment in multiple bin systems, one mechanical grain elevating device can be used on a number of ground level bins. Hoppering a bin floor for complete gravity removal of material is an alternative to the use of a flat-bottom bin unloader. Both devices involve material that reposes in the bin. Some adjustment for the storage loss associated with a hopper floor should be included in any cost comparisons. Elevating a bin and hoppering a bin are two separate but complementary methods of storage unloading and they should be so considered in analyzing systems and costs. The cost of a given system of storage unloading, either gravity or mechanical, is a function of the total amount of material handled and the handling cycle. Gravity flow usually 167 involves opening a slide valve. In contrast, the mechanical . system may involve equipment set—up prior to operation. If the set-up occurs once per bin per year, it is probably in- significant. A set—up repeated many times per year may be highly significant. The cost data presented should be used only as a guide in estimating a system for a specific situation. Local prices for all components should be used in preparing a final estimate. In preparing cost estimates of different systems or system components, only the additional costs should be con- sidered. If batch assembly for commercial processing in— volves a given quantity of labor, this quantity should be deducted from labor charges for on-the-farm processing, since batch assembly labor is required in both operations. The form in which a given grain material is to be stored is a critical problem in the selection of a grain- feed handling system. The use of high moisture corn storage methods may ultimately eliminate ear corn handling. High moisture storage, handling, and feeding methods are still largely in an experimental stage. The apparent cost re— duction opportunity in handling and feeding a high moisture product, however, place conventional storage and handling methods in a critical perspective. um!“ -' 4 IX. SUGGESTED FUTURE STUDIES There are two general alternatives in studying materials handling on the farm. One is to study a specialized segment of the total problem, and the other is to consider the over- all problem. If a specific outline of a materials handling system is the goal, the segment approach is preferable. The reason is that a meaningful system, in this author1s opinion, can only be developed when each segment is identified and developed to an optimum extent. There are, however, general studies that can be con- ducted considering the total farm materials handling problem. An extension of the design fundamentals as outlined in this thesis might be an example. Some studies that appear worthy of consideration in- clude: l. A study of grain processing methods and systems for livestock farms. 2. A study of methods and systems for distributing and feeding grain-feed to livestock. 3. A study of set-up and knock-down time in rela— tion to operating time for farmstead tasks with various degrees of mechanization. 168 4. 169 A study of methods and systems for handling forages. The development of materials handling fundamentals applicable to all farm materials. A study of methods and systems for handling fertilizer on the farm. A study of methods and systems for handling liquid manure in centralized swine feeding. An analysis of the impact of centralized feeding of livestock on total production efficiency and cost. 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Tam // m / u / .om. m _ 0A O a . I 8 w 8 Q. U.. on. AHm .hoHHHHS “mogsomv HdMZuszo 92¢ «made .Bzoo 3mmom mmemz