Manufacturing varieties include: bore 63 mm - 400 mm Φ , stroke 3000 mm (schedule according to user needs design) under single scale, double telescopic column and all kinds of jacks. The manufacturing capacity is equipped with traditional boring - rough, fine honing oil cylinder and boring rolling process, and then fumble for a set of perfect cold drawing - oil cylinder processing technology. Seal selection of domestic well-known manufacturers or imported high-quality products. The anti-corrosion of the parts is electroless nickel - phosphorus alloy or chromium plating, the coating has good wear resistance and corrosion resistance, and the life span of the workpiece is greatly improved.