2 self drilling screws

The design of an M8 wedge anchor is simple yet effective. It consists of a threaded rod with a nut and washer, accompanied by a wedge-shaped expansion sleeve. When installed, the anchor is drilled into a pre-drilled hole in the concrete, and then the bolt is inserted and tightened. As the bolt is tightened, it pulls the wedge-shaped sleeve against the sides of the hole, creating friction and causing the sleeve to expand. This expansion locks the anchor securely in place, providing a strong hold that can withstand significant loads.

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Metal expansion nuts, often referred to as expansion anchors or expansion inserts, are specialized fasteners that expand when a bolt or screw is threaded into them. They typically consist of a cylindrical body with slits along its length or an expandable design that facilitates outward expansion. The main purpose of these nuts is to create a secure grip within a substrate, such as concrete, wood, or metal, thereby preventing loosening due to vibrational forces, temperature fluctuations, or stress.


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