... -2000, GB/T 6728-20024) Use: construction structure, machinery making, container, hall structure, sun seeker, offshore oil field, sea trestle, motorcar ... structure, shipbuilding, automobile axle pipe and so on.5) Packing: square shape bundles wrapped with strong steel strip or according to ... or beveled ends8) OEM available 9)Certificates: CE,CCS Seamless square tubes used in cranes