A continuous or intermittent grooves or depression of the border of the weld and the mother material, commonly known as "biting meat"
(1) Harm
Bite the edge will reduce the effective cross -sectional area of the mother material, reduce the carrying capacity of the structure, and also cause stress concentration to develop into a crack source.
(2) Cause analysis
The welding current is too large, the arc is too long, and the angle of the electrode is incorrect;
During the horizontal welding, the arc stays at the uphill exit for too long; the arc heat is too high, that is, the current is too large, and the transportation speed is too small;
The angle between the strip and the workpiece is incorrect; the swing is unreasonable; the arc is too long; the unreasonable welding order will cause the bite; the magnetic polarization of the arc during DC welding is also a reason for the bite edge.
(3) Control measures
Correct operational posture;
Selecting reasonable welding parameters, using a good way to transport bars will help eliminate bite;
When welding welding (welding flange), replacement of DC welding with AC welding can also effectively prevent bite.
