This is a list of types of threaded fasteners, including both screws and bolts. __TOC__
Fasteners with a tapered shank American name British name Description chipboard screwparticle board screw Similar to a drywall screw, except that it has a thinner shank and provides better resistance to pull-out in particle board, while offset against a lower shear strength. The threads on particle board screws are asymmetrical. Tapconsmasonry screwConfast screwmulti-material screwblue screwself-tapping masonry screwTiten A stainless or carbon steel screw for fastening wood, metal, or other materials to concrete or masonry. Concrete screws are commonly blue in color, with or without corrosion coating. They may either have a Phillips flat head or a slotted hex washer head. Nominal (thread) sizes range from and lengths from . Typically an installer uses a hammer drill to make a pilot hole for each concrete screw and a powered impact driver to drive the screw. The drill hole should be 1/2" longer than the depth penetration of the screw. The screw itself should be drilled a minimum of 1" into the concrete to hold effectively and a maximum of 1-3/4" or the threads will wear and will lose holding power. Ideally 1-1/4" to 1-1/2" of screw thread in the concrete. So for example, if a 1/2" board is being screwed onto the concrete, a 1-3/4" to 2" concrete screw should be used. deck screw Similar to drywall screw, except that it has improved corrosion resistance and is generally supplied in a larger gauge. Most deck screws have a type-17 (auger type) thread-cutting tip for installation into decking materials. They have bugle heads that allows the screw to depress the wood surface without breaking it. double-ended screwdowel screwhanger bolt handrail bolt Similar to a wood screw but with two pointed ends and no head, used for making hidden joints between two pieces of wood.A hanger bolt has wood screw threads on one end and machine threads on the other. A hanger bolt is used when it is necessary to fasten a metal part to a wood surface. drive screwhammer drive screw Chiefly used for attaching manufacturers data plates to equipment. Smooth round or mushroom headed with a multi-start thread on the shank, beneath which is reduced diameter shank that acts as a pilot. The screw is fastened by hitting the head with a hammer and is not intended for removal. drywall screw Specialized screw with a bugle head that is designed to attach drywall to wood or metal studs, but it is a versatile construction fastener with many uses. The diameter of drywall screw threads is larger than the grip diameter. eye screwscrew eyevine eyeloopheaded screw screw eye Screw with a looped head. Larger ones are sometimes called lag eye screws. Designed to be used as attachment point, particularly for something that is hung from it.A vine eye (in the UK at least) is similar to a screw eye, except that it has a proportionally longer shank and smaller looped head. As the term suggests vine eyes are often used for attaching wire lines across the surface of buildings so that climbing plants can attach themselves. lag boltlag screw coach screw Similar to a wood screw, except that it is generally much larger running to lengths up to with diameters from in commonly available (hardware store) sizes (not counting larger mining and civil engineering lags and lag bolts) and it generally has a hexagonal drive head. Lag bolts are designed for securely fastening heavy timbers (post-and-beam, timber railway trestle bridges) to one another, or to fasten wood to masonry or concrete. The German standard is DIN 571, Hexagon head wood screws.
Lag bolts are usually used with an expanding insert called a lag in masonry or concrete walls, the lag manufactured with a hard metal jacket that bites into the sides of the drilled hole, and the inner metal in the lag being a softer alloy of lead, or zinc alloyed with soft iron. The coarse thread of a lag bolt and lag mesh deform slightly, making a secure, near watertight, anti-corroding, mechanically strong fastening. mirror screw This is a flat-head wood screw with a tapped hole in the head, which receives a screw-in chrome-plated cover. It is usually used to mount a mirror. Has sharp threads that cut into a material such as sheet metal, plastic or wood. They are sometimes notched at the tip to aid in chip removal during thread cutting. The shank is usually threaded up to the head. Sheet metal screws make excellent fasteners for attaching metal hardware to wood because the fully threaded shank provides good retention in wood. Twinfast screw A Twinfast screw is a type of screw with two threads (i.e. a twin-start screw), so that it can be driven twice as fast as a normal (i.e. single-start) screw with the same pitch. Drywall screws designated as fine are the most common screws to use the twinfast style of threads. A metal screw with a sharp point designed to attach two pieces of wood together. Wood screws are commonly available with flat, pan, or oval-heads. A wood screw generally has a partially unthreaded shank below the head. The unthreaded portion of the shank is designed to slide through the top board (closest to the screw head) so that it can be pulled tight to the board to which it is being attached. Inch-sized wood screws in the U.S. are defined by ANSI-B18.6.1-1981(R2003), while in Germany they are defined by DIN 95 (Slotted raised countersunk (oval) head wood screws), DIN 96 (Slotted round head wood screws), and DIN 97 (Slotted countersunk (flat) head wood screws). Security head screw These screws are used for security purposes and where vandalism and/or theft is likely. The head of this type of screw is impossible to reverse. It requires special tools or mechanisms like spanners, tri-wings, torxes, square drivers, etc. In some screws, the head can be removed by breaking it after installing the screw.
Fasteners with a non-tapered shank American name British name Description anchor bolt A special type of bolt that is set into concrete, with screw threads protruding above the concrete surface to accept a nut. breakaway bolt A breakaway bolt is a bolt with a hollow threaded shank, which is designed to break away upon impact. Typically used to fasten fire hydrants, so they will break away when hit by a car. Also used in aircraft to reduce weight. The term cap screw refers to many different things at different times and places. Currently, it most narrowly refers to a style of head (see the gallery below). More broadly, and more commonly, it refers to the group of screws: shoulder screws, hex heads, counter-sunk heads, button heads, and fillister heads. In the United States, cap screws are defined by ASME B18.6.2 and ASME B18.3.. In the past, the term cap screw, in general, referred to screws that were supposed to be used in applications where a nut was not used; however, the characteristics that differentiate it from a bolt vary over time. In 1910, Anthony defined it as screw with a hex head that was thicker than a bolt head, but the distance across the flats was less than a bolt's. In 1913, Woolley and Meredith defined them like Anthony, but gave the following dimensions: hex head cap screws up to and including have a head that is larger than the shank diameter; screws greater than in diameter have a head that is larger than the shank. Square head cap screws up to and including have a head larger than the shank; screws larger than have a head larger than the shank. In 1919, Dyke defined them as screws that are threaded all the way to the head. A socket cap screw, also known as a socket head capscrew, socket screw, or Allen bolt, is a type of cap screw with a cylindrical head and hexagonal drive hole. The term socket head capscrew typically refers to a type of threaded fastener whose head diameter is nominally 1.5 times that of the screw shank (major) diameter, with a head height equal to the shank diameter (1960 series design). Forged heat-treated alloy examples are high strength fasteners intended for the most demanding mechanical applications, with special alloy formulations available that are capable of maintaining strength at temperatures in excess of 1000 degrees F (587 degrees C).