Piston Ring Scuffing—A Broad Survey of Problems and Practice

Piston ring and cylinder scuffing is frequently experienced at the development stage on most engines. The mechanism is not really understood because of the large number of interacting factors. Since, however, internal combustion engines are made in a wide range of sizes it is possible to view them as a range of scale models and, by studying these on a broad basis, seek general performance patterns. The author describes an investigation of this kind and brings out a relationship between scuffing problems and engine performance, oil consumption and wear rate. He also briefly reviews the present understanding of piston ring operation and gives design guidance and suggests lines of investigation. This process of analysing the performance of a range of existing devices appears to be a technique which can provide useful guidance on design, market planning and forecasting.