Precautions for welding stainless steel pipe fittings

1. In order to prevent corrosion due to heating, welding should not be too long, 20% less than carbon steel welding electrode, arc should not be too long, rapid cooling between layers, and narrow welding path is appropriate.

2. Stainless steel pipe fitting (Stainless Steel Bend) is quick to harden after welding, which is convenient for cracking. If with the typical stainless steel pipe welding, necessary to preheat above 300 ℃ and 700 ℃ after welding at the mercy of slow cooling treatment. If the welding piece cannot be heat treated after welding, stainless steel pipe welding rod should be used.

3. Stainless steel pipe fittings (Stainless Steel Elbow), for the purpose of improving corrosion resistance and weldability, appropriate amount of non-denatured elements such as Ti, Nb, Mo are added, which is better than stainless steel pipe fittings. Acceptance with typical chromium stainless steel electrode, should be above 200 ℃ preheat and at the mercy of 800 ℃ and tempering treatment after welding. If the solder can not be thermal treatment, cr-ni stainless steel welding rod should be used.

4、The welding rod of stainless steel pipe (Stainless Steel Cap) has exquisite corrosion resistance and oxidation resistance. It is widely used in chemical industry, chemical fertilizer, petroleum and medical machinery manufacturing.

5、The coating of stainless steel pipe has titanium calcium type and low hydrogen type. The titanium and calcium type can be used for ac and dc, but the welding is shallow and red at the same time, so dc power supply should be connected as much as possible

6、Stainless steel pipe has certain corrosion resistance (oxidizing acid, organic acid, gas corrosion), heat resistance and wear resistance. General used for power station, chemical, petroleum equipment equipment material. Stainless steel pipe welding is poor, should pay attention to the welding process, heat treatment before the selection of appropriate electrode.

7、Electrode manipulation should link when dry, titanium calcium type should be 1 hour after 150 ℃ drying, low hydrogen type should be 1 hour after the 200-250 ℃ drying (cannot be repeated many times to dry, or coated convenient cracking flake), beware of covering viscous oil and dirt, so as not to cause weld added carbon content and affect the quality of weldment.

8、When stainless steel pipe is welded, carbon is precipitated out by repeated heating to reduce the corrosion resistance and mechanical function.