Cylinder liners, Application : Automobile Industry

Sleeves, as well as being the containment vessel for the combustion process, serve as the thermal interface between the cooling system, engine block and moving parts of the power cylinder. Development of a new liner involves not only ensuring the exacting fit and tolerances to mate the sleeve into its surroundings; it involves extensive and complex Finite Element calculations. These calculations precisely map the force and thermal distribuition within the cylinder and provide the guidelines for producing a profile that is maximizes wall strength and heat distribution necessary in today’s demanding applications.
Cylinder metallurgy is constantly evolving pushed by the technological advances of modern high output, multi-fuel engines. Failure analysis has pointed the way toward better casting techniques as well as higher grade cast iron and steels. Sophisticated heat treating techniques produce sleeves with a greatly increased durability and service life.
The critical, dynamic interior surface of these cylinder liners are machined to exacting specifications in diameter and parallelism. Initial honing produces the crosshatched pattern of valleys required to distribute the engine lubricant. Plateau-honing finishes the process (so named because the resulting surface profile resembles a series of plateaus). The harsh peaks of the initial honed surface (See figure 1) are removed leaving a substantially flat or plateau finish (See figure 2) with much greater ring sealing area, while maintaining a cross hatch pattern of valleys for oil retention.