Compositional Differences:
1. Expansion Bolt: Composed of a countersunk bolt, expansion sleeve, flat washer, spring washer, and hexagonal nut.
2. Expansion Screw: Composed of a screw and expansion sleeve, the tail of the screw is usually conical, with the inner diameter of the cone larger than the inner diameter of the expansion sleeve.
Application Areas:
1. Expansion Bolt: Commonly used for fixing pipe supports/hangers/brackets or equipment to walls, floors, and columns.
2. Expansion Screw: Suitable for situations requiring small holes, high tensile strength, and no protrusion after disassembly, such as wall finishing, maintaining a smooth wall surface.
Performance Grades:
1. Expansion Bolt: Its working principle is that the bolt is driven into the hole and the nut is tightened. The bolt extends outward while the outer metal sleeve remains stationary, causing the expanding head at the bottom of the bolt to expand and fill the hole, achieving a fixing effect.
2. Expansion Screw: Relies on a wedge-shaped slope to generate frictional gripping force. One end of the screw is threaded, and the other end is tapered. It is wrapped in sheet metal (or steel pipe), and half of the sheet metal cylinder has multiple slits. They are inserted together into a pre-drilled hole in the wall, and then the nut is tightened. The nut pulls out the screw, pulling the tapered part into the sheet metal cylinder, thus expanding the sheet metal cylinder and fixing it tightly to the wall.
