Due to the excellent performance of seamless stainless steel pipes, the use of them is very popular, and the price is also very reasonable, so in the downstream spot market, there are often fake and inferior seamless stainless steel pipes, which are fluid pipes.
The treatment method of high-frequency welded pipe is to use special equipment to plan or grind off the original weld, and another method is to hot-roll the welded pipe. Some unscrupulous merchants use this kind of tube to deceive buyers.
The following are the characteristics of this tube. First of all, any planing or grinding will leave traces, and some are still obvious, and sometimes it is more obvious after removing the rust with tools. The manufacturer of this kind of pipe is afraid of taking responsibility, so the quality certificate provided is marked on it. Fluid pipes instead of seamless steel pipes for fluids. The merchants who sell such pipes usually pay according to the theoretical weight, but the real seamless steel pipes exceed the standard thickness and are generally overweight. There are also more professional ones, namely Flaw detection and composition inspection are performed, but these two methods are relatively limited, because it is difficult to identify the hot-rolled welded pipe for flaw detection.
The seamless stainless steel pipe is a product that has been heat-shrinked, and the appearance is more beautiful, so that the overall performance of the stainless steel pipe can be increased.
The common welded pipes on the market mainly include straight seam welded pipes, spiral welded pipes and seamless welded pipes, but both straight seam welded pipes and spiral welded pipes are very recognizable. The difference between seamless welded pipes and seamless steel pipes is mainly reflected in the following aspects.
First of all, welded pipes are usually cut to length, and are usually 6 meters, 9 meters or 12 meters. There are very few seamless steel pipes with fixed lengths, because the factory price increases a lot for the fixed lengths.
Secondly, it can be seen from the cross-section of the stainless steel pipe head. If there is rust, wipe it clean, and if you look closely, you will find the welded area. And if pickling is carried out, it will be more obvious.
In addition, it should be noted that generally thick-walled steel pipes do not have welded pipe counterfeiting, and only thin-walled steel pipes are easily confused, which can actually be distinguished. It can be observed whether the wall thickness of the stainless steel pipe is uniform, because the seamless steel pipe is made of round steel perforation, so usually the wall thickness of the seamless steel pipe will deviate. The raw material is stainless steel strip, so the wall thickness of the welded pipe is very uniform.
