Main welding technology of welded square pipe

　　Welded square tube with narrow blank produces larger diameter welded pipe, and can also be produced with the same width of blank pipe with different diameter welded pipe. However, compared with the same straight seam square pipe, the weld length is increased by 30~100% and the production speed is low.

　　Large diameter or thick welded square pipe, generally made of steel billet directly, and small welded pipe thin-walled welded pipe only needs to be directly welded through the steel strip. Then, after a simple polishing, the wire will be ready. Therefore, small diameter welded pipes are mostly welded longitudinally, while large diameter welded pipes are mostly spiral welded.