The rolling method of cold drawn (rolled) thick-walled seamless steel pipe is more complicated than that of hot-rolled (extruded thick-walled seamless steel pipe). Large-caliber boiler tubes have a hollow section and their length is much longer than the diameter or circumference of steel.According t

The hot-dip galvanizing technology of seamless steel pipes can usually be divided into two types: dip plating and blow platingDip plating: direct water cooling after immersion plating, average thickness of zinc layer is more than 70 microns, galvanizing cost is high, zinc usage is large, used in nor