Attention! These are the issues you should pay attention to when welding!

1. 1. If the tack weld cracks during welding, causing the plate edge to be dislocated or the gap to change, welding should be stopped immediately and welding can be continued only after repair.
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2. The tack weld must not have defects such as cracks, pores, slag inclusions, etc. Otherwise, it must be removed and re-welded. Re-welding should be carried out in the nearby area, not spot welding at the original location; the gap of the butt weld can be 2~4mm when the process is not specified.

3. When welding the longitudinal seam, arc-starting plates and arc-retracting plates must be placed at both ends of the weldment. The arc-starting plates and arc-retracting plates are made of aluminum of the same grade and thickness as the welded parts. When welding the circumferential seam, arc pits should be avoided as much as possible.

4. For the tack weld that will melt into the permanent weld, it is necessary to ensure penetration and remove the oxide layer on its surface (only silver-white is allowed), and make a smooth transition at both ends of the weld to facilitate arc connection, otherwise it should be trimmed. When welding on cold parts, the arc should stay for a while at the beginning of welding, and when the edge of the parent material begins to melt, wire welding should be added in time to ensure penetration of the starting weld.

5. During welding, the black ash and oxide on the surface of the upper weld should be cleaned with a wire brush. Pay attention to the treatment of the crater, that is, the arc closure point. The arc can be struck 10~20mm away from the welding start, and then quickly return to the start of welding. The first layer is welded in a straight line. In order to obtain a good shape, the other layers can be swung horizontally during welding, and stop for a while on both sides to facilitate fusion.