Wood Screw Bolt

Among fasteners, the wood screw, bolt, and threaded stud are the most widely used. The nut can be added to this list. The range of fasteners includes a large number of items, and sometimes items with minimal external differences have different names.

A wood screw is a tapered rod with thread at the end. The head of a wood screw has a straight slot or a cross recess for driving with a screwdriver. The head may be round or countersunk — depending on the head shape, the wood screw is used for particular purposes.

A wood screw is used for permanent joining of two parts. A bolt is used in cases where the parts being joined can be disconnected if needed. In appearance, a bolt is a metal rod with thread on one end and a head on the other. The bolt head can be hexagonal or square. An integral part of a bolted connection is the nut. A bolt is often screwed into a hole with pre-cut thread, in which case it differs from a screw only in head shape.

If the head is hexagonal, it is a bolt. If it is oval with a screwdriver slot, it is a screw.

Difference between a bolt and a wood screw

Each fastener is designed for use under specific conditions. The main difference between a bolt and a wood screw lies in the thread geometry. Wood screws, in turn, are divided into ordinary wood screws and self-tapping screws. Both have an external helical thread, but a wood screw has a more blunt tip, while a self-tapping screw has a sharp tip. The sharp tip of a self-tapping screw allows the use of power tools — a power screwdriver that drives the fastener with little effort.

A power screwdriver is an electric drill with torque adjustment, most often powered by batteries. Fastening with wood screws is widely used in construction for finishing and renovation work: stretch ceilings, cladding panels, and other finishing elements are attached with them. Using a power screwdriver increases labor productivity and joint reliability, which is why self-tapping screws are used more often than plain wood screws.

A bolt has metric thread and is screwed into a nut or hole with the same thread pitch. Metric thread has a triangular profile with a 60-degree included angle. To achieve the required joint strength, wrenches are used, including power wrenches driven by a compressor (compressed air) or by electricity.

Depending on the application, wood screws and bolts are made from appropriate materials. In mechanical engineering, bolts made from various steel grades are used, and where necessary, from non-ferrous metal alloys. To achieve the required strength, fasteners undergo heat treatment. Today, bolted connections are the most common type of fastening: in terms of reliability and manufacturability, they rank first among fastening methods.