Northern Industrial Tools 164612 manual Common Weld Defects See Table

7.2 Common Weld Defects (See Table)

No.	Seam defect	Possible Causes
		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 water.
		Current and voltage are not matched well.
2	Crackle
		Melting depth is excessive; the carbon content of master material’s welding seam is too high.
		The first welding seam is too small when multi-layer welding; 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 impression of pad is too
		deep.
		Welding current and voltage are not matched well.
4	Excessive spatter
		Wire and work piece are not clean.
		Contact tip diameter is too little or large, stick out is too long.
5	Melting depth is	Welding current is too low; wire stick out is too long.
	too shallow	Poor fit up; angle and gap are too small
6	Others	Contact customer service

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