Profile: Fujian Dongya Machinery Co., Ltd. is a manufacturer of piston rings. We are an ISO 14001 and 45001 certified company. Piston ring is a metal elastic ring with a large outward expansion deformation, which is assembled into the corresponding annular groove of the section. The reciprocating and rotating piston rings rely on the pressure difference of gas or liquid to form a seal between the outer circular surface of the ring, the cylinder, one side of the ring and the ring groove.