Duplex 2205 Pipe Welding Most commonly used are SMAW, GTAW, SAW.
In general, FCAW is not used for the best, it is ugly, difficult to control, and the heat input is large, and GMAW is also not used.
Good solderability and low thermal cracking tendency. Generally, there is no need to preheat before welding, no heat treatment after welding, and welding with dissimilar steel such as 18-8 austenitic stainless steel or carbon steel. In terms of process, the welding process of ordinary austenitic stainless steel is sufficient.
In order to obtain a considerable proportion of post-weld structure, it is critical to know the line energy when welding 2205 duplex steel. It should not be too big or too small. In order to avoid the grain growth too fast or coarse, control the heat input and try to take the welding current at a small point. The interlayer temperature is preferably controlled within 100 degrees.It’s suggest ed that the ferrite content should be measured during welding and after welding. If there is a technical agreement, it must be evaluated according to the technical agreement!
In a certain range, the current must be small. When welding, pay attention to the arc not too long, otherwise it will be easy to vent.
Duplex steels have various brittleness tendencies and should not be used under working conditions above 300 degrees.
The protective gas cannot be used with Ar+Co2. Since one of the most important characteristics of duplex steel is its nitrogen content, it is recommended to use Ar+1~3% nitrogen, and the back protective gas is recommended to use pure nitrogen.
Original and published by Duplex Pipe KAYSUNS