1, Argon arc welding.
Stainless steel welded pipe requirements penetration penetration, no oxide inclusions, heat affected area as small as possible, tungsten inert gas protection of the TIG welding has good adaptability, high welding quality, good penetration performance, its products in the chemical, Nuclear industry and food and other industries are widely used. Welding speed is not high, which is the shortcomings of argon arc welding, in order to improve the welding speed, the general use of three electrode welding torch welding, welded steel pipe wall thickness S ≥ 2mm, welding speed than the single torch to improve 3-4 times, quality also improved. TIG welding and plasma welding can be welded to a larger wall thickness of the steel pipe, in addition, 5-10% hydrogen in argon, and then use high-frequency pulse welding power supply, but also improve the welding speed.
2, High frequency welding.
High frequency welding with a higher power, for different materials, the outer diameter of the steel pipe can achieve a higher welding speed. Compared with the argon arc welding, it is more than 10 times the maximum welding speed. Therefore, the production of general-purpose stainless steel pipe has a high productivity. Because high frequency welding speed, to the pipe to remove the burrs to bring difficulties. At present, high-frequency welding stainless steel tube is not acceptable for the chemical industry, the nuclear industry, which is one of the reasons. From the welding material, high-frequency welding can be welded all kinds of
austenitic stainless steel tube. At the same time, the development of new steel and the progress of forming welding methods, but also successfully welded ferritic stainless steel AISI409 and other steel.
3, Combined welding technology.
Combined welding methods are: argon arc welding plus plasma welding, high frequency welding plus plasma welding, high frequency preheat plus three torch argon arc welding, high frequency preheat plus plasma argon welding. Combination welding to improve the welding speed is very significant. For the use of high-frequency preheat combination of welded steel pipe weld quality and conventional argon arc welding, plasma welding, welding operation is simple, the entire welding system easy to achieve automation, this combination is easy with the existing high-frequency welding equipment convergence, investment Low cost, good efficiency. Stainless steel welded pipe welding methods have their own advantages and disadvantages.
