Evaluating the draft force and soil-tool adhesion of a UHMW-PE coated furrower

To reduce soil-tool adhesion followed by an improvement in draft force, many attempts have been made on the surface modification of moldboard ploughs by applying plastic coatings to them. Like moldboards, furrowers may also show adherence to soil according to its physical condition. This research aimed at draft force improvement of furrowers using surface coatings. Due to the self-scouring ability and low frictional characteristics of ultra high molecular weight polyethylene (UHMW-PE), a narrow metal furrower has been coated with the plastic. For comparison, a steel tine equal in shape and dimension to the plastic-coated tine has been built. The tines were designed like the furrowers and were tested for draft force in a linear soil bin filled with heavy clay soil. Each experiment was repeated three times over a depth of 20 cm with two different compactions and gravimetric moisture content of 4% and 18% dry based. The average draft force value of the polythene coated tine was significantly lower at both moisture levels. In high compacted soil with 18% MC (gravimetric moisture content), the draft force of the UHMW-PE coated tine measured 29% less than that of the steel tine. In conclusion it has been found that the modification to the furrower tines by UHMW-PE coating can reduce draft force significantly.