Self-tapping screw
When the tapping screw is used on the coupled member, the threaded joint may not be pre-made. Use the screw to directly tap the thread when connecting. It is often used to join thin metal sheets. The varieties include taper self-tapping screws and flat end self-tapping screws.
Self-tapping locking screw
The self-tapping locking screw not only has self-tapping, but also has low screwing torque and high locking performance. Its thread has a triangular cross section, and the surface of the screw is hardened to have a high hardness. Its thread size is M2~M12.
Screw common problems and solutions
1. The head of the screw is deformed and the head is snoring. The possible reason is that a die of the screw mold is poorly installed and improperly adjusted.
2. The head of the screw is not round. The reason is that the selection of the die of the screw die is not good or the punching is not full enough.
3. The screws have burrs or burrs. The reason is that the die is poorly formed, mainly because the gap between the punch and the die hole is too large or the punch is too short.
4. The head of the screw is cracked and the screw head has cracks. The reason may be that the quality of the screw wire itself is problematic, so the screw wire must be inspected by the quality department before starting the test. Especially for stainless steel screw wire, it is necessary to check out that it is stainless steel 201, which is stainless steel 304. It is also possible that a die is used incorrectly (such as a die with a hexagonal slider for the disk head), and the viscosity of the lubricant is invalid.
