Possible defects that may occur during the welding process 1. Edge biting: Improper selection of welding parameters or incorrect operation methods result in grooves or indentations. 2. Incomplete penetration: The root of the welded joint is not completely penetrated 3. Welding through; During the welding process, molten metal flows out from the back of the base metal and forms a perforation phenomenon. 4. Weld bead; Metal nodules formed when molten metal flows onto the unmelted base metal outside the weld seam during the welding process. 5. Not fused; The phenomenon of incomplete melting and bonding between the weld seam and the base metal or between welds during welding. 6. Melting pit; The point like pits on the surface of the wood in the area formed on the back of the weld due to excessive welding current or improper operation. 7. Biased welding; The weld deviates from the base metal and is not fully bonded to the base metal. 8. Splashing; Metal particles that scatter around during the welding process. 9. Stomata; The gas remaining in the weld pool during welding cannot escape the voids during solidification. Carbon dioxide gas shielded welding causes air to invade the weld pool due to gas problems, resulting in porosity in the weld seam. 10. Arc pits and arc pit shrinkage cavities; The sunken part generated at the end of the weld seam is called an arc pit; Arc pit shrinkage refers to the depression at the end of the weld bead that is not eliminated before or during the subsequent weld bead welding process 11. The weld size does not meet the requirements; If the surface of the weld seam is irregular [i.e. the surface is excessively rough]; 12. Leakage welding: The phenomenon where there is a weld seam in the drawing design but it is not welded due to operational errors is called leakage welding. 13. Crack: A gap formed by the destruction of the bonding force of metal atoms in a local area of a welded joint under the combined action of welding stress and other brittle factors, resulting in a new interface with sharp notches and large aspect ratios. 14. Slag inclusion: The residual slag in the weld seam after welding is called slag inclusion. 15. Poor penetration: In welding that requires single-sided welding and double-sided forming, if the reverse forming is irregular (sharp, uneven thickness), the reverse forming (penetration) deviates from the connection between the two welded parts, and there is no penetration or the penetration does not meet the specified length requirements, it is called poor penetration. 16. Misalignment: During assembly, the parallel deviation of the center line of the board or the length direction of the board edge is caused by the misalignment of two welding components
