How to solve cracks for a MIG welding

Are you panicking when you see the cracks after welding process?

Why does it appear?

There are many kinds of cracks,we are here to analyse and get the solution.

Reason:

(1) If the slotting angle is too small, pear-shaped and weld bead cracks will occur during high-current welding.

Preventive measures:

(1) Pay attention to the matching of the appropriate slotting angle and the current, and increase the slotting angle if necessary.

Reason:

(2) The carbon content of the base metal and other alloys are too high (weld bead and thermal shadow zone).

Preventive measures:

(2) Use electrodes with low carbon content.

Reason:

(3) When multi-layer welding, the first layer welding bead is too small.

Preventive measures:

(3) The first weld metal must be sufficiently resistant to shrinkage stress.

Reason:

(4) Improper welding sequence, resulting in excessive binding force.

Preventive measures:

(4) Improve the structural design, pay attention to the welding sequence, and conduct heat treatment after welding.

Reason:

(5) The welding wire is wet and hydrogen gas penetrates into the weld bead.

Preventive measures:

(5) Pay attention to the preservation of the welding wire.

Reason:

(6) Poor adhesion of the sleeve plate causes unevenness and stress concentration.

Preventive measures:

(6) Pay attention to the accuracy of the weldment assembly.

Reason:

(7) The cooling is slow due to the excessive welding of the first layer (stainless steel, aluminum alloy, etc.).

Preventive measures:

(7) Pay attention to the correct current and welding speed.