What is partial arc blowing? Causes of arc partial blow?

 

The phenomenon that the arc column deviates from the axis of the stud is called arc partial blow.

 

When the arc blow occurs, the strong melting of one side of the stud will occur, resulting in a small amount or almost no weld flesh on one side of the stud, while the weld flesh on the other side is too large, accompanied by the generation of air holes, or even the stud may not be vertical, which may affect the welding strength.

 

The partial arc blow often occurs in the long-term arc stud welding, while the stored energy stud welding almost does not occur, while the short-term arc stud welding seldom occurs. The longer the welding time is, the greater the possibility of arc partial blow is.

 

Partial arc blowing may be caused by the following reasons:

 

Influence of stud material (low carbon steel is easy to cause partial arc blowing)

 

• magnetic field interference (so called "magnetic bias blowing")

 

Interference of peripheral current equipment (such as interference caused by the operation of electric welding machine)

 

• shape influence of workpiece itself

 

• welding at the edge of the workpiece

 

• during long cycle welding under shielding gas

 

• when the stud diameter is large

 

The partial arc blowing is generally caused by external factors and has nothing to do with the quality of the welding machine itself.