Technical Delivery Conditions the technical delivery conditons for the circular, square and rectangle hollow section bars, which don't need heat treatment after cold forming, are difined. Specification Outside diameter: 219.1mm-3048mm Wall thickness:5.0mm-30.0mm Featrues The raw materials of the same width can be processed in different molding angles to manufacture steel pipes in various diameters.The spiral steel pipe shaping method ensures that the pipe will be round and straight in shape withour any straightening procedure. Materials We use A25-X100 steel type to manufacture ASTM A252 steel pipe. Zhongshun is an ASTM A252 SSAW steel pipe manufacture and supplier. We also offer ERW steel pipe, black steel pipe and coating steel pipe, etc. Our hight quality products are offered at competitive prices. Zhongshun is located in China, where the full chain of manufacturing pillings and galvanized steel pipes can be completed, even in one city, which helps save our production cost. Our lower manufacturing cost saves your purchasing cost.