Modern technologies of strengthening working bodies of soil processing machines

Abstract

During the operation of soil tillage machines, their working bodies, which are in direct contact with the soil, are exposed to abrasive wear, high contact and dynamic loads, as well as the corrosive effect of the soil. Heavy operating conditions cause intensive wear of such parts. Therefore, works related to increasing the wear resistance of materials intended for the manufacture of working bodies of tillage machines (ploughshares, cultivator paws, disks, chisels, etc.) are relevant. The main strengthening technologies presented on the market for the working bodies of tillage machines are considered. Data on the percentage ratio of the market volume by certain types of strengthening were collected and analyzed. Separate characteristics of the considered methods of strengthening tillage bodies are shown in comparison. To ensure wear resistance and technical resource at the same level as the best foreign analogues, it is recommended that tillage bodies be made by casting from high-strength cast iron, heat treated, reaching its bainite metal base, saturated with carbides, in particular on the surface. It is advisable that one surface layer of the metal be of increased hardness, which will meet the condition of self-sharpening of the working organs during wear. Two methods of hardening are considered to fulfill this condition, in which water is used as a cooling medium for heat treatment of the plow blade. At the same time, a new feature of the isothermal tempering of ploughshares developed by us is the use of heated metal equipment, in the given examples of the quality of which ploughshare casting was used repeatedly. The features and advantages of cooling castings in a fluidized bed of sand are also considered. Replacing expensive materials, alloys and technologies with the use of unalloyed high-strength cast iron with a wear-resistant structure, as well as the use of low-cost casting methods together with thermal strengthening will lead to a significant reduction in the cost of the working bodies of tillage machines. Keywords: technologies of strengthening, quenching, wear, working bodies of soil tillage machines, plow, high -strength cast iron.