SSAW steel pipe often there will be some quality problems in the production and use, affecting normal use in some aspects, the need for spiral welded pipe to identify the quality, according to a certain way and performance testing, can produce significant in actual use role, then how to identify counterfeit spiral welded pipe method: the appearance often pockmarked face phenomenon. Generally the whole proportionate amount would be better, mainly taking into account the cumulative error and probability theory this problem. Some of the above please add if inadequate, we welcome the discussion of knowledge about aspects of the steel pipe together, advances constantly exchange. Pock is due to badly worn groove spiral welded pipe surface irregularities caused by uneven defects. Because of shoddy spiral welded pipe manufacturers have to pursue profits, rolling groove most often exceeded. The surface is easy to produce scarring.
Quality spiral welded pipe of uniform composition. High tonnage cold shear machine, cutting head end surface smooth and tidy, and shoddy materials due to the poor material, cut the first end surface there are often off the meat of the phenomenon that is uneven, and no metallic luster. And because of shoddy materials manufacturers cutting products less head, head and tail will be a big ears. Diameter size fluctuations. Folding is formed on the surface of a variety of spiral welded pipe polyline, this defect is often longitudinally throughout the entire product. Causes folding due to shoddy manufacturers to pursue high efficiency, reduction is too large, resulting in the ears, generated under a rolling folding, the product will crack when folded bending, strength thick spiral welded large decline. Easily scratched.
The reason is shoddy material manufacturers poorly equipped, easy to produce burr, scratching the surface of the spiral welded pipe. Depth scratch reduce the intensity of seamless steel pipe. Prone to folding. Transverse ribs thin and low. Often sufficient dissatisfaction with the phenomenon, because manufacturers to achieve large negative tolerance, finished before the reduction of a few relatively large, iron-type small, pass sufficient dissatisfaction. Easy to crack. The reason is that it is blank adobe, adobe many pores, adobe in the cooling process due to thermal stress, cracks, after after rolling there crack.
