Oil Control Ring

Piston Rings are subject to wear as they rub up and down the cylinder bore. To minimize this, BECO Piston Rings are made of wear resistant materials (cast irons and steels) and coated or treated to enhance the wear resistance. Typically top and oil control rings are coated with Chromium or Nitrided, possibly Plasma Sprayed or have a PVD (physical vapour deposit) Ceramic coating. For enhanced scuff resistance and further improved wear most modern diesel engines will have top rings coated with a modified chromium coating. The lower oil control ring is designed to leave a film of lubricating oil a few micrometres thick on the bore, as the piston descends. Three piece oil ring, i.e. with two rails and one spacer, is used for gasoline engines.