NPR's unrivaled Piston Rings and Pistons will satisfy the needs of today's higher performance engine. All Piston Rings and Pistons listed in this catalog are the results of NPR's many years of engineering knowledge and experience taking into consideration material composition and surface treatment design. The function of the piston and the loads that act on it present a special requirements profile for the piston material. Diesel Engine Fundamentals DOE-HDBK-1018/1-93 DIESEL ENGINES DIESEL ENGINES One of the most common prime movers is the diesel engine. Before gaining an understanding of how the engine operates a basic understanding of the engine's components must be gained. This chapter reviews the major components of a generic diesel engine. Piston ring materials are subject to a complex stressing system under mainly dynamic mechanical and tribological loads. Such loads call for the use of materials with high strength (chiefly at temperatures of 200-300°C) especially in the elastic range, which also have the necessary wear characteristics for operation in normal and dry The main piston has a large piston rod extending downwards from the piston to what is effectively a second smaller-diameter piston. The main piston is responsible for gas sealing and carries the piston rings. The smaller piston is purely a mechanical guide. It runs within a small cylinder as a trunk guide and also carries the gudgeon pin. 1.1 In case of graphite coated pistons always rebore the cylinder to the diameter of the piston plus the specified cold clearance (CL) as stamped on the piston crown. Check the accuracy of the cylinder bore with a bore gauge. 2. When fitting a piston pin, gently push in the pin or if this is not possible, heat the piston in an oil bath Piston rings seal the combustion chamber, conduct heat from the piston to the cylinder wall, and return oil to the crankcase. Piston ring size and configuration vary depending on engine design and cylinder material. Piston rings commonly used on small engines include the compression ring, wiper ring, and oil ring. All modern engine pistons are made from an aluminum alloy. The alloy behaves somewhat differently under use according to how the piston is made, so an understanding of the manufacturing process is important. Until the 1970s, the subject of cast versus forged pistons frequently was a debated En mecanique, un piston est une piece rigide de section generalement circulaire coulissant dans un cylindre de forme complementaire. Le deplacement du piston entraine une variation de volume de la chambre, partie situee au-dessus du piston, entre celui-ci et le cylindre. Developments in materials for pistons A R Baker, DirectorofEngineering, BrieoEngineeringLtd, HolbrookLane, Coventry, West Midlands CV6 4BG & S Gazzard, Chief Metallurgist, (Wellworthy Ltd)AEplc, Cawston House, Rugby, Warwickshire CV22 7SB. Piston material is usually nothing special, 1018 aluminum etc. The wear ring on the piston protects the tube from galling to piston. Some also have a ring of brass brazed on and machined to size. If you are going to weld it leave it oversize and then machine to size after welding. Effect of Alloying Elements on High Temperature Mechanical Properties for Piston Alloy Chang-Yeol Jeong+ Department of Nuclear and Energy System Engineering, Dongguk University, 707 Seokjang-Dong, Gyeongju 780-714, Korea Recent legislative and environmental pressures on the automotive industry to produce light-weight fuel-ef?cient vehicles Eff