来源：http://www.kazinobg.com/ 发布时间：2022-03-15 浏览次数：
In order to ensure the long-term safe operation of heat-resistant steel welded joints under high temperature, high pressure and various corrosive media, the performance of welded joints of automatic pressure vessel welding machine shall meet the following requirements.
1. The equal strength heat-resistant steel joint of the joint shall not only have the short-time strength at room temperature and high temperature basically equal to the base metal, but also, more importantly, have the high-temperature endurance strength similar to the base metal.
2. The hydrogen resistance and oxidation resistance of the joint. The heat-resistant steel joint shall have basically the same hydrogen resistance and high-temperature oxidation resistance as the base metal. Therefore, the alloy composition and content of weld metal shall be basically consistent with that of base metal.
3. Structural stability of the joint. During the manufacturing process, especially the thick wall joint, the welded joint of heat-resistant steel will undergo multiple heat treatments for a long time. During the operation process, it will be affected by high temperature and high pressure for a long time. There shall be no obvious structural change and embrittlement or softening in each area of the joint.
4. Brittle fracture resistance of the joint although most of the heat-resistant steel pressure vessels work at high temperature, the hydrostatic test of 1.25 times the design pressure will be carried out at room temperature after the manufacturing of the pressure vessel and pipeline is completed. After installation and maintenance, it shall go through the process of hydrostatic test and cold start. Therefore, the welded joint of heat-resistant steel should also have certain brittle fracture resistance.
5. Physical homogeneity of the joint. The welded joint of heat-resistant steel shall have basically the same physical properties as the base metal. The thermal expansion coefficient and thermal conductivity of the weld metal shall be basically the same, so as to avoid the thermal stress of the joint during high-temperature operation.
The above is the detailed introduction of Shandong CNC welding equipment. I hope it will help you If you have any questions, you are welcome to contact us We will provide you with professional service http://www.kazinobg.com