Configurations and Materials of Oil Control Rings to Meet the New Internal Combustion Engines Requirements

The fuel economy and gaseous emissions features have led the engine developments for the last few years. Various actions taken to meet these objectives imposed the necessity of components, in this case oil control rings, with higher mechanical resistance, durability and efficiency during the engine life.

A new nodular cast iron alloyed with Niobium was developed. The presence of Niobium carbides raises significantly the wear resistance of this material.

New configurations of oil control rings with taper faces or barrel faces showed a better performance if compared with two-piece conventional rings. The contact surface height variation during the engine life (and also the mean specific contact pressure variation in the ring land and cylinder wall contact) brings benefits in the oil consumption reduction without compromising the durability of rings and cylinders.