H8~H9 honed tube for hydraulic cylinder 1. Factory sell 2. OD: 10-630mm 3. ASTM,DIN ... ~1mm/m4 Inside Roughness:0.4~0.8umsteel pipes for hydraulic useMaterial: C20, CK45, etc. also ST52 if given enough ... , Electrical Power, Coal, Machinery, Low and high-pressure boiler, hydraulic prop and so on.InvitationWelcome to Our two factories. I ... : http://www.cnxinglong.cn H8~H9 honed tube for hydraulic cylinder