Hints for determination of the reasons of IC engine crank mechanism bearings damage

In order to reduce the risk of premature wear or sudden failure of slide bearings it is necessary to take the relevant preventive steps. These can be determined on the ground of damage investigation and analysis of their causes. This paper presents some suggestions as to find causes of bearing failure, taking into account operational conditions, loads, applied lubricant and the quality of mating surfaces. A precise recognition of different causes of bearing failures should allow to reduce the hazard of premature wear and to take relevant preventing steps.Remarks on determination of bearing damage presented above and examples of damage presented in references try to show both to user and manufacturer their possible causes. If frequency of definite failure is occasional, most probably it results from unsuitable conditions of bearing operation (e.g. contaminated lubricating oil, oil film rupture, high temperature) or improper assembly (e.g. unsuitable bolt tightness, erroneous bearing clearance) of a certain engine. If damage concerns an entire engine family, one common cause should be defined. A precise recognition of damage various causes allow to diminish the hazard of premature wear by taking the appropriate preventing steps. Because of that very careful examination of the nature and distribution of any damage traces is recommended. Most often the research provide valuable hints how to construct, manufacture, assembly and operate bearings.