How to identify inferior seamless steel pipes

Due to the excellent performance of seamless stainless steel pipes, they are very popular in use and the prices are very reasonable. Therefore, in the downstream spot market, fake and shoddy seamless stainless steel pipes appear from time to time, which are fluid pipes. In fact, this kind of pipe is processed high-quality Frequency welded pipe.
The way to deal with high-frequency welded pipes is to use special equipment to plan or grind off the original welds. Another way is to hot-roll the welded pipes. Some unscrupulous merchants use this kind of pipe to deceive buyers.
Let’s talk about the characteristics of this pipe. First of all, everything that is planed or ground away will leave traces, some of which are very obvious, and sometimes it becomes even more obvious after using tools to remove rust. Because the manufacturers of this kind of pipe are afraid of taking responsibility, the quality certificates they provide are marked with Fluid pipes instead of seamless steel pipes marked with fluids; Merchants selling such pipes usually have to settle based on theoretical weight, but the real domestic seamless steel pipes exceed the standard thickness and are usually weighed; there is also comparison, that is Conduct flaw detection and composition inspection, but these two methods are more limited, because it is difficult to identify hot-rolled welded pipes by flaw detection.
Seamless stainless steel pipes are products that have been heat-shrunk and have a more beautiful appearance, which increases the overall performance of the stainless steel pipes.
The common welded pipes on the market mainly include straight seam welded pipes, spiral welded pipes and seamless welded pipes. However, straight seam welded pipes and spiral welded pipes are very easy to identify. The difference between seamless welded pipes and seamless steel pipes is mainly reflected in the following aspects.
First of all, welded pipes are usually of fixed length, and are usually 6 meters, 9 meters or 12 meters. Seamless steel pipes are rarely available in fixed lengths because the factory price for fixed lengths is high.
Secondly, you can look at the cross section of the stainless steel pipe head. If there is rust, wipe it clean. If you look carefully, you will find the welding area. And if pickling is performed, it will be more obvious.
In addition, it should be noted that generally thick-walled steel pipes will not have counterfeit welded pipes. Only thin-walled steel pipes are prone to confusion, but they can actually be distinguished. You can observe whether the wall thickness of the stainless steel pipe is uniform. Because seamless steel pipes are made of round steel perforations, there are usually deviations in the wall thickness of seamless steel pipes. Although welded pipes have been processed by welding bars or thermal expansion, they are The raw material is stainless steel strip, so the wall thickness of the welded pipe is very uniform.