Tribological properties of the plate valve and rotor material of hydraulic vane motor on different ambient temperature

Abstract

Deck machinery that is driven by the hydraulic motor is a key part for ship exploration in the polar area. In this paper, the hydraulic vane motor in deck machinery was taken as the research object. The material of motor shields was QT350-22L, which was used as the plate valve, and the rotor material was LC2-1. The rotor slides relative to the plate valve under the pressure of the high-pressure oil, and the surfaces worn damage. Wear tests were performed using a pin-on-disk structure under six different temperatures (room temperature (25 °C), 0 °C, −10 °C, −20 °C, −30 °C and −40 °C), two kinds of hydraulic oil(15# and 10# aviation hydraulic oil) and the two normal loads(150 N and 300 N)respectively. In order to analyze the wear mechanism of the friction test specimen under different condition, the surface morphology of the friction test was carried out by scanning electron microscope(SEM) and laser interference profilometer. As the temperature decreased, the coefficient of friction did not change linearly. At the temperature of −20 °C, the coefficient of friction was the smallest, and when the temperature was lower, the coefficient of friction increased slowly and finally stable. Moreover, typical wear and tear modes were different at different test temperatures. The factors were the mechanical properties of the material and the lubrication medium changed in the low temperature. Changes in oil properties affected oil film thickness and distribution and abrasive grain removal ability between friction pairs. According to the experimental results, the paper summarizes the failure mechanism of the hydraulic motor, which can not only optimize the design of the hydraulic motor but also provide reference data for the establishment of online intelligent fault diagnosis system of the marine hydraulic system.