magnet in Baoding City petroleum machinery co., Ltd. consists of seven patents inventor Zhang Zhihua, created in 1985. for a dozen years, our company is committed to high-tech research and development work, strong technical force, advanced processing means, product quality is reliable, has been through a number of oil fields access review to achieve ISO9000 quality certification standards. for many years, our independent research and development of proprietary products, four series, nearly the variety, applied to all areas of transportation and storage of oil field oil extraction, injection,, has been promoted and applied, used to good effect. has made great economic benefits.