Tractive performance of cage wheels with opposing circumferential lugs

Experiments were conducted in a laboratory soil bin with clayey soil to determine the tractive performance of cage wheels as affected by opposing circumferential lugs, lug spacing and wheel slip. Also, the performance was compared with conventional or normal cage wheels. The power of the modified wheels reached a peak at about 30-40% wheel slip depending on the circumferential angle and lug spacing. The modified wheels with 15 degrees circumferential angle at 24 and 30 degrees lug spacings showed significantly higher tractive power compared to other combinations. Although the power of the modified wheels was higher than that of the conventional wheels, the traction efficiencies between the modified and normal wheels were not significantly different. The average wheel slip at the peak tractive efficiency was about 34% for all circumferential angles and lug spacings. Based on the performance and cost of materials, the cage wheel with opposing circumferential angled lugs at 15 degrees circumferential angle and 30 degrees lug spacing is recommended for the design of power tillers in Thailand. (C) 2001 Silsoe Research Institute.