Petroleum machinery co., ltd belongs to several units of Sinopec.

Secondary unit. Petroleum Machinery Co., Ltd. is a listed company specializing in the design, research, processing, manufacturing, sales service and export trade of petroleum machinery. It is a secondary unit of Sinopec and a subsidiary of Sinopec. Sinopec refers to China Petrochemical Group Co., Ltd., a super-large petrochemical enterprise group reorganized by the state on the basis of the former sinopec group in July 1998.