Expansion nail classification:
In terms of material, it is divided into metal expansion nails and plastic expansion nails, and in terms of installation methods, it is divided into screw-in expansion nails and percussion expansion nails.
Fixed principle:
Expansion nails are composed of screws and expansion tubes. The tail of the screw is conical: the inner diameter of the cone is larger than the inner diameter of the expansion tube. When the nut is tightened, the threaded rod moves outward. Axial movement by thread. The cone is used to move, and then a large positive pressure is formed on the outer circumference of the expansion pipe. In addition, the angle of the cone is small, so that frictional self-locking is formed between the wall, the expansion pipe and the cone, thereby achieving a fixed effect. The expansion nail uses the friction force generated by the expansion caused by the wedge-shaped slope to achieve the fixed effect.
Application range:
It is generally used for the fastening of guardrails, awnings, air conditioners, etc. on cement, brick and other materials.
However, its fixation is not very reliable. If the load has a large vibration, it may loosen or fall off.
Instructions:
1. Prefabricate holes of suitable size for expansion nails in the connection base.
2. Insert the expansion nail into it.
3. Expand the sleeve to make it firmly fixed with the base.
4. The diameter of the drilled hole cannot be larger than the diameter of the expansion pipe.