1. Visual inspection, the surface of the nut after welding has relatively uniform burns, which is a relatively normal phenomenon. If only the local burn is severe, the welding may fail. Three solder joints can be clearly seen on the back of the welded part. If one or two of them are not obvious, it is possible that the welding quality is not good enough.
2. After the visual 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 falls off very easily, without any tearing of the base metal, it is a virtual weld.
3. For nut welding, torque detection is used more in our process. Set the required torque value, and then screw the nut. If the nut is not detached and the base material is not deformed when the torque value is reached, the welding quality is qualified. Conversely, if the nut is screwed off without reaching the set torque value, it is unqualified. Torque testing is also a non-destructive testing method.
Fourth, in addition to the torque, the pressure resistance value of the welding nut can also be detected by the press. Set the pressing speed according to the pressure test requirements, and then press down until the nut is separated from the substrate. At this time, the maximum value of the pressure can be recorded, and then judged by comparing with the standard requirements, and at the same time, it can be seen whether the nut is brought out of the base material.
