Division of Information Technology, Engineering and the Environment
Agricultural Machinery Research Design Centre
Agricultural Machinery Research Design Centre
Pull and Lift Forces on a Cage Wheel Lug when operating in wet clay soil.
Power-tillers are widely used for farming in Thailand. They are always equipped with cage wheels when working in paddy fields. This research work was conducted to improve the performance of the cage wheels. Factors affecting the cage wheel lug forces were investigated to help the optimisation of cage wheel design. The aim of this work was to study the effect of lug angle, wheel diameter, wheel slip, sinkage and soil moisture content on cage wheel lug forces, when operating in wet clay soil.
Experiments were conducted in a soil bin made by the Agricultural Machinery Research and Design Centre, University of South Australia. Four model flat lugs of dimensions 100 by 100 mm with lug angles of 0, 30, 45, and 60 were used in the experiments. The forces acting on the lugs were measured at different wheel diameters, lug sinkage, lug slip and soil moisture content.
It was observed that a 45 lug provided the highest average peak pull force while a 60 lug provided the highest lift force. The lug angle, wheel diameter and lug sinkage were found to have a significant effect on both pull and lift forces on the lugs. It was also observed that the effect of lug slip on the pull forces was larger than on the lift forces. When testing with soil of 21% moisture content, the lug slip had a significant effect on both pull and lift forces. However, when testing with soil of 18% moisture content, the lug slip had significant effect only on the pull forces. The effect of lug slip on the lift forces was found to be statistically non-significant.
When the lug forces obtained from the test with 18% and 21% soil
moisture content were compared, it was observed that increasing soil
moisture content considerably decreased the pull and lift forces
produced by the lugs.
