Підвищення технічного ресурсу і довговічності робочих органів ґрунтообробних сільськогосподарських машин

Abstract

The working bodies of tillage agricultural machines (ploughshare, plow shelf, cultivator paw, harrow disc) work in conditions of abrasive operation, shock loads and the impact of external aggressive environment. Their repair is to restore the original size of parts and wear resistance of functional work surfaces. During the operation of tillage machines and units, the working surfaces are subjected to uneven wear, which reduces the life of parts and increases the cost of their replacement and restoration. The working bodies of tillage agricultural machines (ploughshare, plow shelf, cultivator paw, harrow disc) work in conditions of abrasive operation, shock loads and the impact of external aggressive environment. Their repair is to restore the original size of parts and wear resistance of functional work surfaces. During the operation of tillage machines and units, the working surfaces are subjected to uneven wear, which reduces the life of parts and increases the cost of their replacement and restoration. The current level of operation of agricultural machinery is characterized by increased speeds and high productivity, which, in turn, leads to increased wear of parts. accordingly, the reliability of the recovered machines will depend on the wear resistance and fatigue strength of the recovered parts. The leading place in the repair of machines is occupied by welding and surfacing processes, which account for about 80% of all restorative parts. Surfacing makes it possible to obtain layers of any thickness and chemical composition on the working surfaces of parts; apply a welded layer with different properties, ie high hardness and wear resistance. In this work we use point (point) hardening, which consists in micro-dripping of the hard alloy into the surface structure of parts that undergo intense abrasive wear. The geometry of the hardening point is a spherical sector, which facilitates the rapid removal of heat from the surfacing bath in the base metal and the environment, so the hardening points harden at high speed and in a short time. At point strengthening of details one of the main conditions providing stable quality of process - coordination of welding current and arc voltage. The sawtooth profile of the ploughshare blade (cultivator paws) is maintained throughout its service life. providing effective cutting even with the blades worked.