drywall screw manufacturer in china

The reason why there are black spots in wire mesh welding is that the action of wire feeding should be timely filled in the melting time, and the development should be appropriate. There is no argon gas, long burning, large current, long distance, blunt tungsten needle and high molten pool temperature are the fundamental reasons for blackening. Continuous burning, is about active welding machine energy selection, machine welding will appear black spots.