Counterfeit welded stainless steel pipe is easy to produce folding, folding is the surface of stainless steel pipe formed a variety of polylines, this defect often runs through the entire product longitudinal. The reason for the formation of folding is due to the excessive pursuit of high efficiency by shoddy manufacturers, the amount of pressure is too large, resulting in the formation of ear in the pipe, the next rolling when the formation of folding, folding products after bending will crack, the strength of stainless steel pipe will be significantly reduced. Fake and shoddy welded stainless steel pipe appearance will have hemp phenomenon.
Hemp is due to heavy rolling groove wear caused by the irregular uneven surface of stainless steel defects. Secondly, the surface of shoddy stainless steel pipe is easy to scar, the formation of the main reasons are two points, one is poor quality welded stainless steel pipe material is not uniform and many impurities.
The other is shoddy pipe manufacturers to guide the sanitation equipment is simple, easy to stick steel, these impurities bite into the roll after easy to form scarring situation.
Fake stainless steel pipe surface is also easy to form cracks, because its billet is billet, the pores of the billet is very many, the billet in the cooling process because of the role of thermal stress, the formation of cracks, after rolling there will be cracks. Poor quality welded stainless steel pipe surface without metal luster, will show a pale red or similar to pig iron color, the formation of two points, one is its billet is billet. The other is shoddy pipe rolling temperature is not standard, steel temperature is through visual inspection, so can not be in accordance with the prescribed Austenite area to do rolling, stainless steel pipe performance will naturally not meet the standards. Counterfeit welded stainless steel pipe is also easy to scratch, because shoddy welded steel pipe manufacturers production equipment is simple, easy to form burrs, scratch the steel surface, deep scratches will also weaken the strength of stainless steel pipe. The transverse bars of shoddy welded stainless steel tubes are thin and low, often resulting in dissatisfaction.
Because manufacturers to achieve a large negative tolerances, the first few lines of the finished product under the pressure of a large amount, the iron type is small, the hole type is also filled with dissatisfaction. The cross section of the shoddy welded stainless steel pipe is elliptical, which is because the manufacturer saves the material, and the amount of the finished roller er dao under the pressure is too large. Poor quality stainless steel pipe negative tolerances usually exceed the provisions, inferior stainless steel pipe contains a lot of impurities, stainless steel pipe material density is low, and the size of the super difference is also more serious, so if there is no vernier caliper, it can be weighed and checked.