Spiral tube of defined

Spiral tube , also known as spiral steel pipe, is low carbon steel or low-alloy structural steel strip by a certain helix angle (called molding angle) rolled into a tube, then the tube is made of welded seam, it can with a narrow strip production of large diameter pipe. Spiral is mainly used for oil, natural gas pipelines, and its specifications diameter * wall thickness. There spiral welding and double-sided welding, pipe should ensure hydrostatic testing, tensile strength and cold bending properties of the weld compliance.