At current, the major soldering methods of stainless steel welded tube used in industry are argon arc welding, high frequency welding, plasma welding and laser welding. Several welding methods have their own characteristics, argon arc welding and high frequency welding are widely used at present. Let's take a look at several welding techniques for welded pipes.
Stainless steel welded tube technology - argon arc welding
Stainless steel welded tube need deep welding, no oxide, heat affected area as small as possible, tungsten inert gas protection argon arc welding adaptability, high welding quality, good welding performance, products are widely used in chemical, nuclear industry, food and other industries.
Low welding speed is the disadvantage of argon arc welding. In order to improve the welding speed, argon arc welding with three-electrode torch is generally adopted. The wall thickness of the welded steel pipe is S≥2mm, and the welding speed is 3-4 times that of the single torch, and the welding quality is also improved. The combination of argon arc welding and plasma welding can be used to weld steel tubes with thicker walls. In addition, the 5-10% hydrogen in argon can also be used to increase the welding speed through the high-frequency pulsed welding power supply.
Stainless steel welded tube technology - high frequency welding
Frequency welding has a higher power provide, for distinct materials, the outside diameter wall thickness of the steel tube can achieve a higher welding velocity. Compared with argon arc welding, welding speed is more than 10 times. Therefore, generally used stainless steel pipe productivity is higher.
Because of the high frequency welding speed, it is difficult to remove the burr in the welded pipe. At current, high frequency welded stainless steel tube is not accepted by the chemical and atomic industry, this is too one of the reasons. From the welding material point of view, high-frequency welding can weld various types of austenitic stainless steel tubes. At the same time, the development of new steel types and the progress of forming welding methods have successfully welded ferrite stainless steel AISI409 and other steel types.
Stainless steel welded tube technology - combination welding technology
Combined welding methods include: argon arc welding and plasma welding, high-frequency welding and plasma welding, high-frequency preheating and three welding torch argon arc welding, high-frequency preheating and plasma argon arc welding. Combination welding significantly improved the welding speed. For the weld quality of high frequency preheated composite welded steel pipe, plasma welding is equivalent to conventional argon arc welding, welding operation is simple, the whole welding system is easy to automate. The combination is easy to connect with the existing high frequency welding equipment, low investment cost, good benefit.
Each welding method of stainless steel welded tube has its own advantages and disadvantages. It is a new trend of the development of stainless steel welded pipe technology that how to cultivate the advantages and form a new welding process combining several welding methods to meet the requirements of quality and production efficiency of stainless steel welded pipe.
Post time: May-04-2023