Why does stainless steel welded pipe undergo annealing?
Why should stainless steel welded pipe undergo annealing? 2018-11-11 Annealing is a heat treatment process for stainless steel welded pipes. Its purpose is to clean up residual stress, stabilize size, and reduce deformation and cracking tendency. It is difficult to distinguish whether stainless steel welded pipes are annealed with the naked eye, so some methods can be taken to help You can tell, today the editor of the stainless steel welded pipe manufacturer will introduce you some knowledge in this area. 1. The pipe can be judged by echo. Tap the welded pipe with a little stronger force, and listen to the echo at the pipe mouth with ears. If it is an echo sound Higher and sharper, it means that it has been annealed. So why is there a higher echo? It is caused by the more uniform and dense crystals in the annealed parts. Without annealing, there will be more structural defects and will absorb most of the sound waves. Energy, so the echo at the mouth of the tube is relatively small. If possible, you can use sonar to detect. 2. Use a digital multimeter with better accuracy to measure the resistance of each tube per unit length (for example, 2 meters). The resistance of stainless steel is compared Larger, the resistance value after annealing is smaller than the unannealed one. There should be no liquid left on it before the test. It is not that all stainless steel welded pipe manufacturers will go through the annealing process, so you must learn to use the above The method to distinguish annealed stainless steel welded pipes and non-annealed stainless steel welded pipes, so that you can survive the purchase process from buying shoddy products.