Overview of Threaded Fasteners

Bolts and screws are both externally threaded fasteners. Bolts generally fit through unthreaded holes, while screws fit into threaded holes. Nuts are internally threaded fasteners used to tighten bolts. Washers are not threaded fasteners, but they are often used with screws and bolts. Certain nuts and washers provide extra locking action to ensure that joints stay tight. Threaded fasteners are the most commonly used fasteners. After taking this class, users will be able to identify many different types of threaded fasteners and describe how and when to use them. This familiarity serves as the foundation for learning how to properly select and assemble threaded fasteners, which leads to time and cost savings and prevents fastener failure.