BigPatents India

In an oillness reciprocating air compressor, a piston reciprocates in a cylinder to compress a gas sucked from the outside and the compressed gas is discharged to the outside. The piston has an annular groove on the outer circumference, and a piston ring made of self-lubricating resin composite material is placed in the annular groove. The inner surface of the cylinder has SiC coating to increase the life of the piston ring, thereby allowing the compressor to be used at hight pressure and high temperature efficiently to increase durability.