Spiral steel pipe will be hot rolled strip steel by the spiral bending forming, with automatic submerged arc welding seam and seam welding spiral steel pipe. Double wire, double submerged arc spiral pipe in the solder layer under the arc welding method using the wire and solder layer between the flux produced by the combustion heat of the arc, the molten solder and base metal wire is formed. However, in the production and use of spiral welded pipe,there will be some quality problems, in some aspects affecting normal use, the need for quality spiral welded pipe for identification, according to certain methods and performance testing, in actual use can have an important the role, then how to identify counterfeit spiral welded pipe method: appearance often pitted surface phenomenon. Generally the whole amount would be better proportionality, mainly taking into account the cumulative error and probability theory this problem. The above points if inadequate please add, we welcome the discussion about Pipe knowledge, in constant communication progress. Ma face serious wear and tear due to rolling groove surface irregularities caused by uneven spiral welded pipe defects. As shoddy spiral pipe manufacturers have to pursue profits rolling groove rolling most often exceeded. Surface is easy to produce scarring.
Spiral welded pipe quality ingredients evenly. The tonnage of high cold shear, cut head face smooth and neat, but shoddy material because material is poor, there are often cut off the meat head end of the phenomenon, that is uneven, and no metallic luster. And because shoddy material manufacturers products less cutting 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 line, this defect is often longitudinally throughout the product. Folding is due to produce shoddy manufacturers pursuit of high efficiency, reduction is too large, resulting in the ears, is produced under a rolling folding, folding products will crack after bending, thick-walled spiral welded pipe strength decreases. Easily scratched.
Reason is false and inferior material factory equipment simple and easy to produce burr, scratch surface of spiral welded pipe. Deep scratches will reduce the strength of the seamless steel tube and prone to fold, even transverse reinforcement and low. Often appeared phenomenon of discontent, because manufacturers finished product quantity of the previous way slants big, small iron type, groove filling to achieve big minus tolerance. Because its billet is adobe, adobe air, adobe in the process of cooling due to the effect of thermal stress, cracks, after rolling there is crack.
