The surface of stainless steel welded mirror stainless steel sheet pipe is a common defect of welded stainless steel welded pipe, which is specifically manifested as compression, indentation and scratches. Bruising: Bruising refers to the damage of the roller hole to the surface of the stainless steel welded pipe blank, there are many types of bruising, but the causes of bruising are not only the following aspects:

(1) Adjust the bottom line of a pair of roller tables to be higher than the rolling brushed stainless steel sheet bottom line; The rolling line produces uneven fluctuations;
(2) The vertical roller is too tight;
(3) Vertical roller elevation;
(4) The new hole may be that the chamfer of the hole edge is too small or the chamfer does not meet the requirements;
(5) High-strength stainless steel stainless steel welded pipe welded pipe blank has greater rebound and deformation resistance, and the hole edge is easy to bite into the stainless steel welded pipe blank;
(6) The vertical roll before the flat roller is not enough to apply force to the stainless steel welded pipe blank, so that the wider stainless steel welded pipe blank enters the fixed width of the flat roll hole, and the stainless steel welded pipe blank is "cut" by the hole type;
(7) The flat roller is low, and the lower edge of the vertical roller hole is damaged by the stainless steel welded pipe blank.