spiral welded steel tube Technique: ERW Thickness: 0.8-8.0mm ... .D: 20-220mm Standard: GB, BS, ASTM A53-2007, AP spiral welded steel tube1. Out Diameter: 20mm - 220mm2. Thickness: 0.8mm ... SPEC 5L, ASTM, BS, GB/T9711.1-1997 Low pressure liquid pipe:1) Nominal OD: 21.3 - 194mm (1/2" - 7 ... consumers!According to customer demand production of special specification pipe. spiral welded steel tube