The demand for refined oil, ethylene and three major synthetic materials (plastics, synthetic rubbers and synthetic fiber) is gradually increasing with the development of offshore oil, land oil and natural gas. As a result, a large number of oil and gas pipeline gathering equipment and large-sized efficient petrochemical equipment are required, with the oil exploration equipment and drilling equipment used in the development of desert and ocean in particular. Therefore, the annual amount of auxiliary equipment and maintenance parts for the petrochemical equipment such as bearings, machinery seals, stuffing static seals etc. will increase dramatically in demand.