Zhongyuan steel pipe company professionally produces the spiral steel pipe.The spiral steel pipe is also called SSAW Steel Pipe.Technology of production:DSAW(Double Submerged Arc Welded) and ERW(Electric Resistance Welded).The standard:SY/T5037-2000, GB/T9711.1-1997,sizes:219~2220(outer diameter)*4-30mm(wall thickness).