countersunk self drilling screws for metal

The incorporated washer, on the other hand, serves multiple purposes. Primarily, it increases the bearing surface, thereby distributing the load from the screw more evenly across the material it's screwed into. This prevents damage to the surface, such as splitting or indentation, which can occur when a screw is tightened without a washer. Additionally, the washer can also help in reducing friction and preventing loosening due to vibration.

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The heavy hex head bolt consists of a threaded shank and a large hexagonal head, which provides a larger surface area for better grip and torque transmission. The head design also prevents the bolt from turning during installation, ensuring a secure fit. The thread pitch and diameter of the bolt are crucial factors that determine its mechanical properties, such as tensile strength and shear strength. Generally, heavier bolts have greater strength due to their increased material volume.

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