What are the common welding methods for nickel-based welded pipes?
We also need to have a general understanding of the welding process of nickel-based welded pipes, and we also need to have a general understanding of the common welding methods. Let's talk about the common welding methods for stainless steel welded pipes.
Nickel-based welded pipe production process-argon arc welding
Nickel-based welded pipes require deep melting, no metal oxides, and the heat-affected zone is as small as possible. Tungsten gas-protected argon arc welding has good adaptability, high welding quality, and good penetration performance. Its products are widely used in chemical plants, China's nuclear industry, food and other industrial production.
The low welding speed is a shortcoming of argon arc welding. In order to increase the welding speed, argon arc welding with three electric j welding torches is generally used. The wall thickness of the welded steel pipe is S≥2mm. The welding speed is 3-4 times higher than that of a single welding torch, and the welding quality is also improved. Argon arc welding and plasma welding can weld seamless steel pipes of higher thickness. In addition, 5-10% radon gas in the argon gas cylinder and the use of high-frequency pulse welding power supply can also increase the welding speed.
Nickel-based alloy pipe production process-high frequency welding
High frequency welding has a high power rating, and can achieve a high welding speed for seamless steel pipes of different materials, diameters and thicknesses. Compared with argon arc welding, it is more than 10 times the welding speed. Therefore, it has a high production efficiency in manufacturing stainless steel pipes for general purposes.
Due to the high speed of high frequency welding, it is difficult to clean the burrs inside the welded steel pipe. At present, high frequency welded stainless steel pipes are not yet accepted by chemical plants and China's nuclear industry, which is one of the reasons. From the perspective of welding materials, high frequency welding can weld various types of low alloy steel pipes. At the same time, the development of new steel grades and the development of forming welding methods have also successfully welded steel grades such as 430 stainless steel AISI409.
Stainless steel welded pipe production process-combination welding technology
Combination welding methods include: argon arc welding plus plasma welding, high frequency welding plus plasma welding, high frequency heating plus three-torch argon arc welding, high frequency heating plus plasma plus argon arc welding. Combination welding significantly increases the welding speed. The weld quality of seamless steel pipes welded by high-frequency heating is very similar to that of basic argon arc welding and plasma welding. The welding is easy to use and the entire welding system is easy to automate. This type of composition is easy to connect to the existing high-frequency welding USB, with low investment and good economic benefits.
