Revisiting the pitch angle of the cutting edge of the plough-share to the furrow bottom

Abstract

Mold board soil cultivating is the most power-intensive operation in crop production. Decrease of power consumption of plowing by the plow body is possible in case of change of the pitch angle of the cutting edge to the furrow bottom. Thus cutting by the cutting edge is carried out directly by a cutting edge and part of a facet. The cutting edge creates the maximum main tension, part of a facet - the minimum main tension. The pitch angle of the cutting edge to a furrow bottom has to be such that the elastic deformations excluding destruction of soil particles prevailed at influence of facet part. The expression connecting a pitch angle of the cutting edge to a furrow bottom from the elastic making relative strain of the compression schedule, the plowing depth, length of the fragmented part of the cutting edge is received. Rising of size of an elastic component and depth of plowing increases a pitch angle. The elastic component of relative soil deformation was defined from the analysis of the curve of compression received at destruction of samples with a cylindrical form by pull test machine RM-0.5. It was established that with increase of value of absolute humidity of the loamy soil the elastic component of relative deformation changes on parabolic dependence, accepting a maximum at absolute humidity of the soil (24 percent). For all sizes of plowing depth the pitch angle increases with rising of absolute humidity. The minimum angle value corresponds to plowing depth of 0.2 m, maximum - of 0.25 m. At absolute humidity of 25 percent and plowing depth of 0.2 m the pitch angle makes 2.8 degrees, when depth of 0.25 m - 3.52 degrees. It was established that for the loamy tilth soil the maximum value of a tilt pitch angle of the cutting plough share edge to a furrow bottom should not be above 4 degrees.