Repair of Power Hydraulic Cylinders Using New Polymer Composite Materials

Abstract

The development and implementation of a new repair technology based on the use of polymer parts made of high-performance antifriction composites in tribo-couplings of power hydraulic cylinders will reduce the cost and repair time, significantly increase the reliability of the entire hydraulic system. (Research purpose) The research purpose is in increasing the efficiency of repairing of power hydraulic cylinders of agricultural machinery by restoring tribo-conjugations with new antifriction composites based on modified caprolon. (Materials and methods) The article presents the study of the physical and mechanical characteristics of samples of polymer composites according to well- known and original methods. Authors used computer programs and original methods of equipment suppliers in the study of compounding processes, rheological and tribotechnical tests. Theoretical research using the provisions of theoretical mechanics, elasticity theory and thermophysics has been conducted. A numerical study of the introduction of a spherical indenter into a sample of a viscoelastic composite material was carried out using the ANSYS software package, the MAPDL module. (Results and discussion) The article analyzes the obtained data on the elastic-strength, rheological and tribotechnical characteristics of the studied compositions of polyamide composites. The three-component composite containing 2 percent shungite, 0.5 percent graphite, 6 surfactants has the best complex of these properties. It has been proposed to restore the operability of the piston assembly and the front cover during the repair of the power hydraulic cylinder to change their design with the installation of guide support rings made of polyamide composite into the cover and piston of the hydraulic cylinders. This will lead to a significant reduction in the wear rate of the tribo-coupling parts and reduce the complexity of repairing hydraulic cylinders. (Conclusions) Restoration of tribo-couplings of power hydraulic cylinders with the installation of a guide ring made of a new polymer composite ensures a decrease in the maximum contact stresses, the rate of their increase with an increase in the gap and, as a result, a decrease in the wear rate of the contacted parts.