brass self drilling screws

Butterfly screws, also known as wing nuts or butterfly nuts, are a distinctive type of fastener that have gained popularity in various engineering and design applications due to their unique shape and functionality. These screws derive their name from their appearance, which resembles a butterfly in flight when the wings are fully opened. The wings serve as handles, allowing for quick and easy tightening or loosening by hand without the need for additional tools.

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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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At its core, the structure of a bolt consists of a few key components the head, the shank, and the threads. The head is the larger, often hexagonal or square part at one end of the bolt, designed to provide a surface for the application of torque when tightening or loosening the bolt with a wrench. The shank is the long cylindrical part that spans between the head and the threads, and it determines the overall length of the bolt. The threads are helical ridges that spiral around the shank, allowing the bolt to engage with a nut or a threaded hole, enabling a strong clamping force between joined parts.


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