1. Appearance inspection: It is relatively normal for the surface of the nut to have relatively uniform burns after welding. If only local burns are severe, the welding may be unqualified. Normally, three welding points can be clearly seen on the back of the welded part. If one or two of them are not obvious, the welding quality may not be up to standard.
2. After the appearance inspection, in order to quickly determine the welding quality before production, the welding nut will be directly tapped with a tool. If the nut can tear the base material, the welding quality is better. If it comes off very easily without any tearing of the base material, it means it is a false weld.
3. For nut welding, we use torque testing more often in the process. Set the required torque value, and then tighten the nut. If the nut does not come off when the torque value is reached and the base material does not deform, then the welding quality is qualified. On the contrary, if the nut is screwed off before the set torque value is reached, it is disqualified. Torque testing is also a non-destructive testing method.
4. In addition to the torque, the pressure resistance value of the welding nut can also be tested through a press. Set the pressing speed according to the pressure test requirements, and then press down until the nut is separated from the base material. At this time, the maximum value of the pressure can be recorded, and then compared with the standard requirements to make a judgment. At the same time, you can see whether the nut is brought out of the base material.
