1, fillet weld welding, easy to produce defects such as undercut, incomplete penetration, weld sag, so the angle of welding wire should be controlled well. When the thickness is not equal to the thick plate, the inclination angle of welding wire should make the arc biased towards the thick plate, and the thicker the thick plate, the greater the angle between welding wire and it;

2. For fillet welds with welding feet, a single-layer single-pass welding torch should be used to point the welding wire away from the root, and the straight-line moving method should be used for welding; For the weld with welding feet, the welding gun should swing horizontally, and the oblique circle wire feeding method can be used for welding;

3. When the welding leg is large, multi-layer welding should be adopted, and two layers should be welded. When welding, the operation of 1 layer is the same as that of single-layer welding, and the current is slightly higher than usual, so as to obtain welding passes with unequal welding feet. When welding the second layer, the current is slightly lower than 1 layer, and the welding gun should be pointed at the depression of 1 layer weld bead until the required welding leg is reached.

4, fillet weld should adopt multi-layer multi-pass welding, namely welding 3 layers;

5. The weld leg is too large, which makes the deposited metal droop easily, and flash appears on the horizontal plate and undercut appears on the vertical plate. The angle and direction of the welding gun should ensure that an equilateral, smooth and uniform weld is finally obtained.