... price 2. Structure steel pipe, piling pipe, Sewage and clear water transportation. Line pipe for petrole Description(Unit,mm) Round pipe, 20, 22.2, 25 ... 30X30,40X40,45X45,50X50,60X60,70X70and other rectangular or oval pipe of the same specifications. Thickness from 0.85mm to 3mmApplication1 ... UL standard) with the tube6.The construction structure uses the tube 7.The mechanism uses the tube. steel pipe