The study of the wear of the control knives of the straw chopper

Abstract

The article considers the topical task of studying the wear rate of steel parts in the course of agricultural work. The wear of the knives of chopper-cum-spreaders used in agricultural works is determined and compared with control samples. Within the scope of the study, the relative linear and weight wear was being determined. The results of the study of dimensional parameters are given in the article. The dependence of wear on the operating time and zones of various wear of the part is determined. A graphic illustration of these dependencies is provided. The mechanism of wear of these parts is proposed. It was established that it is necessary to change the design of the hardsurfacing overlay used in order to maintain the acceptable cutting properties of the knife until it reaches its limit state, more specifically: firstly, to refuse applying hardening strips of hard alloy on the reverse side of the cutting edges by 1/3 of their length located at a distance of 65-70 mm from the flat end; secondly, to make the width of the strips variable, gradually increasing it to a size 1.5 to 2 times exceeding the blade width when approaching the flat end of the knife, i.e. give them triangular or curvilinear shape that is close to and/or overlapping the boundaries of the wear outline; thirdly, the triangular shape of the strips can be achieved due to the excessive material released from the unhardened 1/3 of the blade length.