Split cast iron piston ring - has outer periphery rolled to achieve compression around circumference to increase wear resistance

摘要

The split seal ring, e.g. a piston ring, made of cast iron is rolled to compress the material in the circumferential direction at the inner and/or the outer periphery of the ring. The compression is uniform over the circumference of the ring. The compression is achieved by a simple rolling operation. Before rolling the ring may be of non-circular shape, a circular shape is attained by rolling until the ends of the blank meet. The method improves the wear resistance of the ring.