Cause Analysis:
1. The material or structure of the self-tapping screw is defective, such as excessive internal stress of the material, excessively deep cross groove, etc.
2. The gear used by the wind batch is too large.
3. The hole position of the fastened part is too small, and the screwing torque is too large.
4. The assembly holes are seriously misplaced and the screwing torque is too large.
5. The tightening sequence of the self-tapping screws is improper, resulting in a large accumulation error of the hole position during assembly, and the self-tapping screws are subjected to excessive shear stress.
6. The specification and model of the self-tapping screw is incorrect.
Solution:
1. Replace the self-tapping screws of the same model from different manufacturers or different batches.
2. Reasonably adjust the small wind batches.
3. Replace or correct the fastened parts.
4. Reassemble to make the hole position meet the standard.
5. Adjust the screw tightening sequence, and try to fix it diagonally.
6. Use self-tapping screws with correct specifications and models.
