Hot dip galvanizing tube is an alloy layer produced by the reaction of the molten metal with the iron matrix, so that the matrix and the coating are combined. Hot-dip galvanizing involves pickling the steel pipe first. To remove the iron oxide on the surface of the steel pipe, after pickling, the steel pipe is cleaned through the aqueous solution of ammonium chloride or zinc chloride or the aqueous solution of ammonium chloride and zinc chloride mixed, and then sent to the hot-dip plating bath. Hot dip galvanizing has the advantages of uniform coating, strong adhesion and long service life.

Straight seam welded pipe production technology is simple, high production efficiency, low cost, rapid development. Spiral welded pipe generally has higher strength than straight welded pipe. Welded pipe with larger pipe diameter can be produced from narrow blank, and welded pipe with different pipe diameters can also be produced from blank of the same width. However, compared with the same length of straight seam pipe, the weld length is increased by 30~100%, and the production speed is lower.

Large diameter or thicker welded pipe, generally made of steel blank, while small welded pipe thin-wall welded pipe only needs to be welded directly through the steel belt can be. Then after a simple polishing, the wire will be fine.

Supplement: welded pipe is welded with strip steel, so in the original position of it is not as high as seamless pipe