butterfly expansion anchors

Washer head machine screws are characterized by their broad, flat heads that resemble a washer. This design provides a larger bearing surface than standard screws, which helps distribute the load more evenly across the material being fastened. The head’s geometry often includes a recessed area for a driver, facilitating easy installation and removal. Additionally, these screws are typically made from high-strength materials such as stainless steel, carbon steel, or alloy steel, ensuring durability and resistance to corrosion and wear.


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A hex washer head bolt is essentially a threaded rod with a hexagonal head, providing a larger surface area than a standard hex bolt. The integrated washer portion of the bolt serves two primary functions. Firstly, it distributes the clamping force over a wider area, preventing damage to the material being fastened and reducing the risk of loosening due to uneven pressure. Secondly, it increases the friction between the bolt and the surface, enhancing the holding power and ensuring a secure connection.

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