Image of an internal combustion engine piston

Piston Ring Design and Operation

This page is intended to help designers and development engineers with the solution of practical problems, involving the pistons and rings of internal combustion engines. It represents a distillation of the contents of about 100 reports and articles which contain useful data, but have probably not been read by many engineers in industry.

The information presented is arranged to give the reader any easy reference to what is known about how pistons and rings actually operate, and about the various problems which occur with them.

The following articles do not represent anything approaching a simple design method, partly because there is still insufficient knowledge available to do this, but mainly because the cyclic variations in pressure, temperature and speed to which piston assemblies are subjected, makes their design and operation too complex for simple design analysis.

It is hoped, however, that the information contained in this report, when combined with previous experience of particular engines, will enable practical engineers to solve design and development problems more readily and effectively.

Articles On Piston Rings

The Mechanisms of Piston Ring Operation

This article of the attempts to condense the available data on the various aspects of piston ring performance into a more complete and readable form than that in which it is otherwise available.

Methods of Designing Piston and Ring Assemblies

This article summarises the design methods for sizing of piston and piston ring assemblies.  It details the design requirements for pistons and rings, typical arrangements depending on the type of engine and the detailed design formulae required for an initial piston and ring design.