A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development

Thesis (M.Eng.) - Asian Institute of Technology, 1992

The locally made tractor mounted whole crop wheat harvester was converted in to a semi mounted version by transferring some of its weight from tractor hydraulic to the pivoted wheel frame. For the selection of suitable tire size for semi- mounted position whole crop harvester, three tire sizes viz, 70 cm (5.50-16), 60 cm (5.50- 14), and 4.50- 12) were studied in laboratory conditions. There was no significant difference found in pull of these tires were dming crossing over an artificial bund made of cemented. A smaller tire size 50 cm (4.50- 12) was selected for whole crop harvester on the basis of cost and stability of machine. The difference between theocratically calculated values and measured values of pull were 1.8 kN, 1.8 kN and 2 kN for 70 cm, 60 cm and 50 cm tires, respectively. The average pulJ required for MF- 240 tractor with whole crop harvester in semi mounted position was 25 percent less than that for MF-265 tractor with harvester in mounted position during crossing over the same bund. The average field capacity and efficiency of harvester were 0.3 ha/h and 61 percent, respectively. Total cost of use for harvesting in semi- mounted position including bhoosa (fine chaff) collection with MF-240 tractor was Rs.1075/ha (Rs.336/tone) as compared to Rs.1242/ha (Rs.355/tone) for a MF- 375 tractor with whole crop harvester in mounted position