Welded steel pipe and tube OD: 21.3.1219mm WT: 1.2-20mm ... .1/2,GB/T 14291,YB/T 4028MATERIAL: Q195, Q215, Q235, GRA, GRB, X42, X52, X56, X60, X65, X70, J55, K55 ... .N80 ETC.SIZE:ERW PIPE: OD: 21.3-508MM WT:2.5-12.7MMSSAW ... , thermoelectricity, project construction, bridge structure, oil and natural gas pressure steel tube. Good quality Welded steel pipe and tube