... ,St 52,St 37,St 44,S355 JO H,S235 JR H(3)OD: 10mm*10mm-600*600mm(4)Wall Thinkness ... rolled, ERW,High-frequency weldedInspection: With Chemical Composition and Mechanical Properties Analysis; Hydrostatic Test, Dimensional and Visual Inspection, Also With Nondestructive ...