Intro to Millwright Practice Exam

The correct classification of bolts and screws hinges on their threading. Bolts are externally threaded fasteners, designed to be installed through an unthreaded hole and typically secured with a nut, which provides the internal threading. On the other hand, screws are also primarily externally threaded, allowing them to cut into their own corresponding internal threads within a pre-drilled hole or to engage directly into materials without the need for a nut. This fundamental distinction underscores why the statement suggesting that both bolts and screws are classified as internally threaded fasteners is false. Neither bolts nor screws have internal threads; instead, they utilize external threading to fasten materials, making the assertion incorrect. The understanding of this classification is essential in understanding the different applications and mechanisms of fasteners in millwrighting.