... price 2. Structure steel pipe, piling pipe, Sewage and clear water transportation. Line pipe for petrole Description(Unit,mm) Round pipe, 20, 22.2, ... 50.8, 57, 63.5, 76, 83, 89 Square pipe 16X16,19X19,20X20,22.2X22.2,25.4X25.4,30X30 ... ,40X40,45X45,50X50,60X60,70X70and other rectangular or oval pipe of the same specifications. Thickness from 0.85mm to ... tube 7.The mechanism uses the tube. steel pipe