Spiral and standard classification: pressurized liquid delivery spiral submerged arc welded pipe (SY5036-83) is mainly used to transport oil, natural gas pipelines; pressurized fluid transport spiral seam high frequency welded steel pipe (SY5038-83), High Frequency lap welding method for pressurized fluid transport spiral seam high frequency welded steel pipe. Strong pressure steel, plastic, and easy welding and machining molding; general low pressure liquid delivery spiral submerged arc welded pipe (SY5037-83), using double-sided automatic submerged arc welding or welding into the legal system for water, gas, air and steam low pressure liquid delivery SAW pipe.