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7.2 Common Weld Defects (See Table)
No.
Seam d efe ct
Poss ibl e Cau ses
Wire and workpiece have excessive oil, rust or water.
1
Gas holes
Insufficient shielding gas coverage (low flow); silicon and manganese content are
insufficient; nozzle is blocked up.
Wire and work piece have excessive oil, rust and wate r.
Current and voltage are not matched well.
Melting depth is excessive; the carbon content of master material’s welding seam is too high.
2
Crackle
The first welding seam is too small when multi-layer w elding; the welding sequence is wrong
and the water content of gas is excessive.
Arc length is too short and welding speed is too fast.
3
Bite side
Welding position is not correct; welding current is too low and the imp ression of p ad is too
deep.
Welding current and voltage are not matched well.
Wire and work piece are not clean.
4
Excessive spatter
Contact tip diameter is too little or large, stick out is too long.
5
Melting depth is
too shallow
Welding current is too low; wire stick out is too long.
Poor fit up; angle and gap are too small
6
Others
Cont act c ust ome r serv ic e