Introduction of innovative technologies in friction units of heavy-duty tribosystems and monitoring of their condition

Abstract

The article describes studies of heavy-duty metal-polymer tribosystems: wheel-brake pad and pyatnik-podpyatnik of rolling stock, as well as spline couplings of the MI-26 helicopter tail rotor transmission. Tests of the wheel - brake pad system were carried out on an inertial stand with two-way braking at loads and speeds close to real operating conditions. Methods for modifying polymers, fillers, and nanoscale additives have been developed for the Pyatnik - podpyatnik tribosystem of rolling stock. To increase the wear resistance of work surfaces two-layer carbon fibers were applied to the spline couplings. DLC- coatings. Bench tests of these coatings showed a 4.5-fold reduction in wear when testing full-scale slots with a load of 30,000 kg. H and the number of completed cycles in 1,000,000. Methods for monitoring spline couplings based on the analysis of the frequency spectrum of the acoustic-emission (AE) vibration signal generated during the operation of the friction unit are considered. The results of studying the working state of spline couplings obtained by vibration diagnostics in the acoustic frequency range are presented. The state estimation is based on both the characteristics of the time signal and the transformation of the signal in the frequency domain using modal decomposition of the signal using Hilbert-Huang transformations. It is shown that for the effective for monitoring heavy-duty tribosystems, it is advisable to use neural networks.