metal expansion nut

The diameter of a foundation bolt is a primary consideration, as it determines the bolt's load-bearing capacity. Larger diameter bolts can withstand greater loads, making them suitable for heavier structures. The length of the bolt, another key factor, is calculated based on the depth of the foundation and the thickness of the connected component. Length also affects the bolt's grip, which is the portion of the bolt that is clamped between the connected parts.

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Screws are another essential type of structural fastener, distinguished by their helical threads. They provide excellent holding power when driven into materials like wood, metal, or plastic. Common screw types include wood screws, machine screws, and self-tapping screws. Wood screws are designed specifically for use in wooden materials, while machine screws are used in conjunction with nuts or tapped holes in metal. Self-tapping screws, on the other hand, create their own thread as they are driven into the material, eliminating the need for pre-drilling.


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