On the Abnormal Piston Ring Wear of a Marine Diesel Engine

抄録

Abnormal wear of piston rings occurs sometimes with recent marine diesel engines because of severer lubrication condition. The authors studied the mechanism of abnormal wear through analyses of the running-in process of the ring under the lubrication condition at high temperature and low speed, and the preventive measures. It was made clear that (1) the occurrence of abnormal wear was expedited by abrasion with hard abrasive generated by scuffing caused by edge loading of rings at the dead centers of stroke, (2) high alkaline cylinder oil lacked in thermal stability and deposited soft abrasive at above 180°C, causing scuffing, (3) the character of the compound of metal arising from added elements was dominant as the influence of the cylinder liner material, and total carbon and silicon contents had little effect, (4) chamfered piston rings and finishing of the liner surface by tool cutting were effective in preventing abnormal wear, etc.