PM--Power and Machinery A Three-stage Soil Layer Mixing Plough for the Improvement of Meadow Soil, Part 3: Field Evaluation

A prototype three-stage soil layer mixing plough was designed and built in Japan, based on the results of the soil bin experiments conducted using a half-size model ploughs described in Part 2 of this paper. This machine was transported to China for field tests and this paper presents the trash mixing rate into the A horizon and the draught of the plough in the meadow soil. The results showed that the optimum approach angle of a second plough body for the meadow soil was 30°. The rolling resistance of the tracked vehicle (T802) on which the plough was mounted was about 10 kN, and the draught of the first plough body which tilled the Ap horizon was also about 10 kN for a working depth of 200 mm and a working width of 500 mm. The draught of the second plough body which tilled the surface of the Ap horizon was about 5 kN for a working depth of 50 mm. The draught of the third plough body increased steeply with the greater working depths. The draught was about 15, 28 and 38 kN, respectively, for working depths of 156, 217 and 278 mm. The wheat stubble and straw were found in the A horizon and even in the layer below a depth of 500 mm.