... : 20#OD:20-660MM WT:5-60MM,Standard: Tianjin large seamless, small seamless, baotou, hengyang, chengdu, exist issues now days, baosteel, anshan ... ? Mm-273 mm, wall thickness 6 mm-60 mm of seamless steel tube, material for: # 20, 45 #, 16 Mn, 27 SiMn ... -2000, ASTMA53, A106, API 5 L / 5 CT, DIN, JIS seamless tube, etc