Influence of operating and disk parameters on performance of disk tools

Studies were conducted in soil bin containing black clay loam and sand in order to assess the draft, vertical and lateral components of reaction in disks at different moisture levels. The selected variables are: disk angle-40, 44 and 48 degrees, tilt angle-16,20 and 24 degrees, disc diameter-51, 56 and 61 cm, and forward speed-4, 7 and 10 kmph. The drafts and lateral reaction components show high values in black clay loam. The vertical reaction decreased with an increase in soil moisture content (MC) in both soils. The increase in draft in black clay loam soil was less when compared to sand with increase in soil moisture. In sand, some sinkage of disks was observed when the MC was increased. The MC range between 13 to 17.18 per cent may provide good working condition in black clay loam soil. At 7 kmph speed, the drafts and the soil reactions were observed to be balanced, which suggests the speed about 7 kmph may be the right operating speed. Larger size and heavier (56 and 61 cm) disks gave satisfactory results in black clay loam soil at low MC level as they showed low upward vertical reaction component which helped in penetration and in sand 51 cm was disk found workable. Disk angles set at 44 degrees were found to justify for the working of disk tools, since the drafts observed were much at lower and higher disk angles. The 16 degrees tilt angle results in lower draft and vertical reaction component (better penetration) as compared to 30 and 24 degrees.