Helical welded pipe is the low-carbon structural steel or low alloy steel strip by the helix angle (called molding angle) rolled into a tube, and then the tube made of seam welded together, it can be used a narrow bandsteel production of large-diameter steel pipe. Helical welded pipes for oil pipeline and gas pipeline specifications diameter * wall thickness.
Helical welded pipes side welding and double-sided welding, the pipe should ensure that hydrostatic test, weld tensile strength and cold performance to meet the requirements.
The process of helical welded pipes is as follows:
Open book - on volume - leveling - butt welding - Milling - molding - welding - Weld - cut pipe - break - the follow-up welding - hydrostatic test
Uses of helical welded pipes:
Helical welded pipes are mainly used in water engineering, petrochemical industry, chemical industry, power industry, agricultural irrigation, urban construction in the country. For the transport of liquids: water supply, drainage. For gas transportation: gas, steam, liquefied petroleum gas. For structural purposes: as piling pipe for bridges; docks, roads, building structure pipe.