expansion anchors

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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The self-drilling aspect of these screws implies that they come equipped with a sharp, drill-like tip that enables them to pierce through materials without the need for pre-drilling a pilot hole. This feature significantly speeds up the installation process and reduces the risk of damaging the material being used. Self-drilling screws are often made from durable materials, such as stainless steel or carbon steel, and are coated with various finishes to enhance corrosion resistance and longevity.


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The 'head' of the bolt refers to its top part that sits above the threaded shaft. It's the part that provides the gripping surface for the tool used in installation or removal. The hexagonal shape offers several advantages over other head designs. Firstly, it allows for better torque application, enabling precise tightening without slipping. Secondly, the six-sided profile can accommodate larger wrenches or sockets, which can generate more torque, ideal for heavy-duty applications.

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