Research on hardness of soot contaminated in diesel engine oil

Abstract

Increase of soot contaminated in engine oil caused by EGR system accelerates diesel engine wear, especially valve train wear. The wear is mainly caused by soot abrasively. It is important to evaluate the hardness of soot to wear protection. In this study, a rig test (Block on ring tester) has been conducted by used oil that contained soot. The test pieces that have different hardness were used to determine hardness of soot. The wear scar caused by soot was observed on the test piece surfaces that were softer than HV1500,but was not observed on the hard surface (HV1930). The hardness of soot was estimated harder than HV15 , softer than HV1930.