MANAJEMEN TENAGA DAN MESIN PERTANIAN (TEP 446) AGUS MARGIWIYATNO SEMESTER GANJIL 2012/2013

Pokok Bahasan : 1.Introduction (0.5 – session) 2.Economic Performance (2.5 – sessions) 3.Power (2 – sessions) 4.Operations (2 – sessions) 5.Cost Determination (2 – sessions) 6.Equipment Selection (3 sessions) Penilaian : Komponen Penilaian : Ujian Tengah Semester (40 %) Ujian Akhir Semester (40%) Tugas Terstruktur (20%) Standar Penilaian : NA >= 85A 70 < NA < 85B 55 < NA =< 70C 40 < NA =< 55D NA <= 40E Buku Pegangan Utama : Donnel Hunt, FARM POWER AND MACHINERY MANAGEMENT. Iowa State University Press.

ECONOMIC PERFORMANCE

Optimum farm machinery management occurs when the economic performance of the total machine system has been maximized to produce goods at a profit. The economic performance of machinery system is measured in terms of cost per unit of output. For example : $120 machinery cost/ha of corn harvested, $40 / t of soybeans grown, 75 cents/kg beef marketed. In this terms maximum system performance occurs when the production cost per unit is lowest. Components of economic performance are : 1.Machine Performance. 2.Power Performance. 3.Operator Performance

Example : A machine system produces 5 t of forage/hr with a machine cost $4/hr. The system requires 1.5 man.hrs and 1.1 tractor.hrs at $3 and $2, respectively. The economic performance of the system is : $1.80 /t => ($4/hr) x (1 hr/5 t) + ($3/hr) x (1 hr/5 t) + ($2/hr)x(1hr/5t) The dimensional units of machine, power, and labour performances are in quantity per time. These three performance figures add to become an economic performance figure when the quantity per time is divided into the cost per time of each component.

Machine Performance

1.Machine Performance. MEASURES of agricultural machine performance are THE RATE and QUALITY at which the operations are accomplished. THE RATE : Is important measures because operations is often sensitive to cost, product demand, season, and bad weather. Operators have to consider the rate of machine to avoid economic penalties resulting from crop damage A rate of machine performance is reported in term of QUANTITY/HOUR :  Most of agric machine performance  area/hour  Harvesting machine performance  tons/hour  Balers machine performance  bales/hour  Processing equipment performance  ton/hour  Such Performance Figures are called MACHINE CAPACITY THE QUALITY : Agricultural material are fragile and many are perishable. Quality of machine operation is related to machine ‘s ability to operate without wasted product. The amount of product damage or reduction in product quality due to machine operation is an important measure of machine performance.

MACHINE CAPACITY Capacity of machine is depended on the type of machine (area/hour or mass/hour) Machine capacities :  Field Capacity (ha/hour)  rate of machine operation in a field  Material Capacity (mass/hour)  total product  Throughput Capacity (mass/hour)  total mass of material through a machine Example : It is determined that a 5-m width-of-cut combine is traveling 1.5 m/s. In one minute’s time 50 kg grain are collected in the grain tank and 60 kg of material are discharge out of the rear of the machine. What is capacity of the machine ?

Field Capacity Field Capacity : [(1.5 m/s) x (5 m/1 ha)] x [(1 ha/ m 2 ) x (3600 s/1 hr)] = 2.7 ha/hr Material Capacity Material Capacity : (50 kg/min) x (60 min/1 hr) = 3000 kg/hr Throughput Capacity Throughput Capacity : [(50kg +60 kg)/min] x [(1 ton/1000 kg) x (60 min/1 hr)] = 6.6 ton/hr The above capacities are theoretical capacities It is usually impossible to operate machine continuously. Therefore, effective or actual capacities will be subtantially less than theoretical or potential capacity. Time element is considered in calculating the effective capacity.

List of time element : 1.Machnine preparation time at the farmstead (includes removal from and preparation for storage, also workshop) 2.Travel time to and from the field. 3.Machine preparation time in the field both before and after operations (includes daily servicing, preparation for towing, etc.) 4.Theoretical field time (the time the machine is operating in the crop at an optimum forward speed and performing over its full width of action) 5.Turning time and time crossing grass water-ways (machine mechanism are operating). 6.Time to load or unload the machine if not done on-the-go. 7.Machine adjustment time if not done on-the-go (includes unplugging) 8.Maintenance time (refueling, lubrication, chain tightening, etc.; if not done on-the-go, does not include daily servicing). 9.Repair time (the time spent in the field to replace or renew parts that have become inoperative) 10.Operator’s personal time. Item 4 to item 9 are the items included in the term FIELD EFFICIENCY

FIELD EFFICIENCY : Ratio of the time in 4 to the total time spent in the field (4- 9). Field efficiencies are not constant values for specific machines but vary widely. Tabel 1.1 list the ranges for some of the common farm machines. With a filed efficiency established, effective field capacity can be determined.