Restoration of hydraulic cylinder rods by method of ESA

Abstract

During the operation of equipment, its structural elements under the influence of frictional forces and the environment are exposed to various types of wear. To maintain the rolling stock in a working condition, it is necessary to systematically carry out a large set of measures, such as maintenance, current and overhaul repairs with periodic replacement and restoration of worn parts and assemblies. It is obvious that maintaining the performance of modern machines requires high technical knowledge and modern technology. It is not uncommon for special machinery, including tractors and various agricultural vehicles, to be equipped with hydraulic power systems to perform various heavy operations. The actuating mechanisms of such systems are hydraulic cylinders. One of the main features of their design and operation is that the main and very precise part - the rod in working order is in an unprotected environment, namely in the open air. The specificity of the work of heavy equipment is high dust content, gas pollution and the presence of various abrasive materials in the work area in the form of stones and soil. Under these conditions, the precision, polished rods are subject to significant wear. In this paper, the possibility of restoring hydraulic cylinder rods for small types of wear (scratches and dents of a depth of no more than 0,3 mm) is considered by the method of electrospark alloying (ESA), with the creation of coatings on their working surfaces that are identical in their characteristics to the new ones. Electrode materials and processing modes were selected. Research was carried out to determine the dynamic microhardness of the created coating.