What is the function of the head of a bolt?

The head of a bolt serves a critical function as it offers a surface for tightening. This means that when a tool, typically a wrench, is applied to the head, it allows the user to apply torque to secure the bolt in place. A well-designed head can accommodate various tool types, such as hex, square, or slotted configurations, ensuring efficiency in the assembly or disassembly of mechanical components.

While the alignment of the bolt and the grip it provides is important, those functions are typically addressed by the shaft and threading of the bolt. Maintaining tension is a result of correctly tightening the bolt but is not a direct function of the head. The primary role of the head is to facilitate the application of force, directly impacting the effectiveness and reliability of the fastened joint.