Anti-wear Testing Method of Engine Oil under Variable Rotating Speed

A variable rotating speed method was proposed to evaluate the anti-wear properties of engine oil based on the lubricant status and work environment of internal combustion engine. This method could simulate the lubrication status of engine in the test process by changing rotating speed to match the oil film thickness. It is based on the Stribeck curve and the elliptical contact theory using a four-ball tester as the experimental platform. The anti-wear properties of eleven kinds of oil were tested and the relevance, repeatability and distinctiveness of the variable rotating speed method and SH/T 0189 method were comparatively investigated. It is found that these two methods were significantly relevant. The performance of repeatability and distinctiveness of variable rotating speed method was much better than that of SH/T 0189 method. The variable speed method may be used for the anti-wear research of engine oil.