How to solve the blackening of 304 stainless steel pipe weld

How to solve the blackening of 304 stainless steel pipe weld
1, Gas supply in advance: gas shall be supplied before welding to ensure the protection of argon on welding parts and prevent oxidation.

2, Delayed gas supply: after the welding gun is closed, continue to supply gas to ensure that the weld and surrounding parts of the weldment are not oxidized by high temperature.
Selection of tungsten needle: tungsten needle should be sharp in use

3, Control of welding gun switch: for 304 stainless steel pipe, continuous welding with large current for a long time is not allowed, and spot welding should be used more. Too much current and too slow welding speed will cause weld blackening. The welding speed shall be fast and the method shall be accurate.

4, The distance between the tungsten needle tip and the weldment, the tungsten needle next to the weldment, and the weld is black; The tungsten needle is too far away from the weldment, and the weld is also black. Ensure the stability and strength of welding arc during welding.

5, The welding wire material shall be selected according to 304 stainless steel pipe to ensure the uniformity of the material and avoid welding blackening due to material difference.