Curiously enough in all the long history of piston engine and compressor development, no basic understanding has been presented of the tribological conditions at the interface between the ring and cylinder, throughout the cycle of operation. This makes design from first principles in this area, difficult indeed.
In 1967, the Committee on Tribology formed a Piston Ring Scuffing Panel to study the problem. The Panel recommended that the Ministry of Technology should encourage work directed towards an understanding of the basic phenomena. This recommendation was accepted and work is still proceeding under the auspices of the Department of Industry. Meanwhile, as the Committee on Tribology has always been most concerned that existing research knowledge should be compounded with current practice to produce better and readily and usable design information, it was decided to commission just such a conversion exercise on the literature of piston ring design.
This demanded an organisation which was both knowledgeable in the mechanical and tribological aspects of ring operation and expert in the difficult data conversion process. The choice fell upon Michael Neale and Associates who had previously prepared for the Panel an excellent broad survey of ring scuffing problems*.
This new survey relating to design, again emphasises the need for continuing work towards full understanding of the interface phenomena, so that the gaps in our knowledge can be sufficiently closed to make a fully detailed design method possible. Until that time, the Committee on Tribology commends this new contribution to those who design, develop, and use pistons, rings and liners, for engines and compressors.
THE PRESENT METHODS OF DESIGN AND DEVELOPMENT OF PISTON
ASSEMBLIES
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Performance requirements;
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typical design arrangements and development
methods;
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detail design and the piston and of the
rings;
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choice of materials,
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coatings and finishes
THE MECHANISMS OF PISTON RING OPERATION SUGGESTED BY
AVAILABLE RESEARCH INFORMATION
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Sealing and blow-by;
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the nature of the ring/cylinder contact;
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oil transfer and control;
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normal wear processes;
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scuffing and other running-in problems.
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Materials, surface treatments and finishes.
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The application to design of the available
research information on the operation of piston rings and cylinder
liners.
