Intro to Millwright Practice Exam 2026 - Free Millwright Skills Practice Questions and Study Guide

The hex nut is designed with a hexagonal shape, which allows it to be easily grasped with a wrench. This feature is essential for applications where the nut needs to be tightened or loosened securely. The six sides of a hex nut provide ample surface area for a wrench to grip, enabling effective torque application without damaging the fastener.

In mechanical applications, the ability to use a wrench on a fastener is crucial for achieving the appropriate clamping force and ensuring that the assembly remains secure under various working conditions. Hex nuts are commonly used in conjunction with bolts, studs, or screws, making them a fundamental component in many mechanical systems. The design and functionality of the hex nut make it ideal for situations that require strong, reliable fastening.

On the other hand, lock washers, cap nuts, and flat washers serve different purposes. Lock washers are intended to prevent loosening under vibration, cap nuts provide a finished appearance and may offer some protection from elements, while flat washers distribute load and prevent damage to the surface being fastened. These fasteners do not have a design that allows them to be turned with a wrench in the same way as hex nuts do, which is why they are not suitable answers to the question.