Spiral welded pipe
Spiral pipes, also known as spiral steel pipes or spiral welded pipes, are made by rolling low-carbon structural steel or low alloy structural steel strips at a certain helix angle (called forming angle) into pipe blanks, and then welding the pipe seams together. It can produce large-diameter steel pipes from narrower strip steel.
Spiral pipes are mainly used for oil and natural gas transmission pipelines, and their specifications are represented by outer diameter * wall thickness. Spiral pipes can be welded on one side or both sides, and the welded pipes should ensure that the water pressure test, tensile strength of the weld seam, and cold bending performance meet the requirements.
The commonly used standards for spiral pipes are generally divided into: SY/T5037-2018 (ministerial standard, also known as spiral seam submerged arc welded steel pipes for ordinary fluid transmission pipelines), GB/T9711.1-1997 (national standard, also known as the delivery technical conditions for oil and gas industry transmission steel pipes - Part 1: Class A steel pipes (GB/T9711.2 Class B steel pipes with strict requirements), API-5L (American Petroleum Institute, also known as pipeline steel pipes; divided into two levels: PSL1 and PSL2) SY/T5040-92 (Spiral submerged arc welded steel pipes for piles).