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Introduction: Spiral steel pipe is a spiral seam steel pipe made of strip steel coil as raw material, often formed by warm extrusion, and welded by automatic double wire double-sided submerged arc welding process. Material: Q235A，Q235B、10#、20#、Q345（16Mn）、L245(B)、L290（X42）、L320（X46）、L360（X52）、L390(X56)、L415(X60)、L450(X65)、L485(X70)、L555(X80)、L290NB/MB（X42N/M）、L360NB/MB（X52N/M）、L390NB/MB(X56N/M)、L415NB/MB(X60N/M)、L450MB(X65)、L485MB(X70)、L555MB(X80)。 
Application: Spiral steel pipes are mainly used in water engineering, petrochemical industry, chemical industry, power industry, agricultural irrigation, urban construction, and are one of the twenty key products developed in China. 
Used for liquid transportation: water supply, drainage, and oil transportation. 
Used for gas transportation: coal gas, steam, liquefied petroleum gas, natural gas. 
Used for structural purposes: pile driving pipes, bridges, docks, roads, building structural pipes, etc.