A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a

rope A rope is a group of yarns, Plying, plies, fibres, or strands that are plying, twisted or braided together into a larger and stronger form. Ropes have high tensile strength and can be used for dragging and lifting. Rope is thicker and stronger ...

in that it is flexible and

curve In mathematics, a curve (also called a curved line in older texts) is an object similar to a line, but that does not have to be straight. Intuitively, a curve may be thought of as the trace left by a moving point. This is the definition that ...

d in compression but

linear In mathematics, the term ''linear'' is used in two distinct senses for two different properties: * linearity of a '' function'' (or '' mapping''); * linearity of a '' polynomial''. An example of a linear function is the function defined by f(x) ...

, rigid, and load-bearing in tension. A chain may consist of two or more links. Chains can be classified by their design, which can be dictated by their use: * Those designed for lifting, such as when used with a hoist; for pulling; or for securing, such as with a bicycle lock, have links that are

torus In geometry, a torus (: tori or toruses) is a surface of revolution generated by revolving a circle in three-dimensional space one full revolution about an axis that is coplanarity, coplanar with the circle. The main types of toruses inclu ...

-shaped, which make the chain flexible in two

dimension In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it. Thus, a line has a dimension of one (1D) because only one coo ...

s (the fixed third dimension being a chain's length). Small chains serving as

jewellery Jewellery (or jewelry in American English) consists of decorative items worn for personal adornment such as brooches, ring (jewellery), rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the ...

are a mostly decorative analogue of such types. * Those designed for transferring power in machines have links designed to mesh with the teeth of the

sprocket A sprocket, sprocket-wheel or chainwheel is a profiled wheel A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the whe ...

s of the machine, and are flexible in only one dimension. They are known as

roller chain Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, pr ...

s, though there are also non-roller chains such as block chains. Two distinct chains can be connected using a quick link,

carabiner A carabiner or karabiner (), often shortened to biner or to crab, colloquially known as a (climbing) clip, is a specialized type of shackle, a metal loop with a spring-loaded gate used to quickly and reversibly connect components, most notabl ...

shackle A shackle (or shacklebolt), also known as a gyve, is a U-shaped piece of metal secured with a clevis pin or Bolt (fastener), bolt across the opening, or a hinged metal loop secured with a quick-release locking pin mechanism. The term also appl ...

, or

clevis A clevis fastener is a two-piece fastener system consisting of a ''clevis'' and a ''clevis pin head''. Terms The ''clevis'' is a U-shaped piece that has holes at the end of the prongs to accept the clevis pin. The ''clevis pin'' is similar to a ...

. The load can be transferred from a chain to another object by a chain stopper.

Uses for chains

Uses for chains include:

Decoration

Belly chain A belly chain or waist chain is the popular English term for the Indian jewelry called ''kamarbandh''. The belly chain is a type of body jewelry worn around the waist. Some belly chains attach to a navel piercing; these are also called "pierced b ...

, type of body jewelry worn around the waist * Jewelry chain, many necklaces and bracelets are made out of small chains of gold and silver *

Chain of office A livery collar or chain of office is a collar or heavy chain, usually of gold, worn as insignia of office or a mark of fealty or other association in Europe from the Middle Ages onwards. One of the oldest and best-known livery collars is the C ...

, collar or heavy gold chain worn as insignia of office or a mark of fealty in medieval Europe and the United Kingdom * Decorating clothing, some people wear wallets with chains connected to their belts, or pants decorated with chains *

Omega chain An omega chain or omega necklace is a pseudo-chain A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compressi ...

, a pseudo-chain where the 'links' are mounted on a backing rather than being interlinked *

Tie chain Tie has two principal meanings: * Tie (draw), a finish to a competition with identical results, particularly sports * Necktie, a long piece of cloth worn around the neck or shoulders Tie or TIE may also refer to: Engineering and technology * ...

, used to hold in place a tie to the underlying shirt front

Power transfer

Bicycle chain A bicycle chain is a roller chain that transfers power (physics), power from the Bicycle pedal, pedals to the Drive wheel, drive-Bicycle wheel, wheel of a bicycle, thus propelling it. Most bicycle chains are made from carbon steel, plain carbo ...

, type of roller chain that transfers power from the pedals to the drive-wheel of a bicycle, thus propelling it. The chain is made up of a number of rigid links that are hinged together by pin joints to provide the flexibility needed to wrap around the bicycle's gears. * * Chain gun, type of machine gun that is driven by an external power source, sometimes connected by a chain, to actuate the mechanism rather than using recoil * Chain pumps, type of water pump where a loop of chain inset discs is passed around then through a tube submerged in liquid *

Chainsaw A chainsaw (or chain saw) is a portable handheld power saw, power saw that cuts with a set of teeth attached to a rotating chain driven along a guide bar. Modern chainsaws are typically gasoline or electric and are used in activities such as t ...

, portable mechanical, motorized saw using a cutting chain to cut wood *

Timing chain In a piston engine, either a timing belt (also called a ''cambelt'') or timing chain or set of timing gears is a perishable component used to synchronize the rotation of the crankshaft and the camshaft. This synchronisation ensures that the engin ...

, used to transfer rotational position from the crankshaft to the valve and ignition system on an

internal combustion engine An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal comb ...

, typically with a 2:1 speed reduction.

Security and restraint

* Ball and chain, a phrase that can refer to either the actual restraint device that was used to slow down prisoners, or a derogatory description of a person's

significant other The term significant other (SO) has different uses in psychology and colloquial language. Colloquially, "significant other" is used as a gender-neutral term for a person's partner in an intimate relationship without disclosing or presuming a ...

(or waist chain), a physical restraint worn by prisoners, consisting of a chain around the prisoner's waist, to which the prisoner's hands are chained or cuffed Prisoner in belly chain

* Bicycle lock (or bicycle chain), lockable chain * Chain boom, large chains used to exclude warships from harbors and rivers * Chain link fencing, fencing that utilizes vertical wires that are bent in a zigzag fashion and linked to each other *

Chain mail Mail (sometimes spelled maille and, since the 18th century, colloquially referred to as chain mail, chainmail or chain-mail) is a type of armour consisting of small metal rings linked together in a pattern to form a mesh. It was in common milita ...

, a type of armor consisting of small metal rings linked together in a pattern to form a mesh. * Door chain, a type of security chain on a door that makes it possible to open a door from the inside while still making it difficult for someone outside to force their way inside * Gang transport chain, a chain used to shackle two or more inmates together for transport or work outside the facility, forming a chain gang * H-style restraints, a combination consisting of handcuffs on a belly chain with a connector chain running down to a set of leg irons * Leg iron chains ( fetters), an alternative to handcuffs * Prisoner transport restraints, a combination which consists of a pair of handcuffs attached by a longer chain to a pair of leg irons * On chain-linked

handcuffs Handcuffs are Physical restraint, restraint devices designed to secure an individual's wrists in proximity to each other. They comprise two parts, linked together by a Link chain, chain, a hinge, or rigid bar. Each cuff has a rotating arm whi ...

, the cuffs are held together by a short chain

Traction, pulling and lifting

* Anchor cable, as used by ships and boats; in British nautical usage the component is a cable, the material is chain ** Selected based o
chain grade, diameter, coil, and either galvanized steel or stainless steel finish
* Chain slings * Chain hoist, device used for lifting or lowering a load *

Chain boat A chain boat,John MacGregor (1867). ''The voyage alone in the yawl "Rob Roy": from London to Paris, and back etc.'', London: Maranda merrill, Son and Marston, pp. 97-99. chain tug or chain-ship was a type of river craft, used in the second half o ...

, a type of river craft that used a steel chain laid along the riverbed for its propulsion * Chain-linked lewis, a self-locking lifting device particularly for stone using a chain link as a pivot * Curb chain, used on curb bits when riding a horse * High-tensile chain (or transport chain), chain with a high tensile strength used for towing or securing loads * Jack chain, a toothed chain used to move logs * Lead shank (or stud chain), used on horses that are misbehaving *

Pull switch A pull switch, also known as pull-cord switch, or light pull, or pull chain is a switch that is actuated by means of a Link chain, chain or pullstring, string. History An electric pull switch is attached to a toggle type switch: one pull to s ...

, an electrical switch operated by a ball chain ** Lavatory chain, the chain attached to the cistern of an old-fashioned W.C. in which the flushing power is obtained by a gravity feed from above-head height. Although most cisterns no longer work like that, the phrase "pull the chain" is still encountered to mean "flush the toilet". * Rigid chain actuator, a type of chain that only bends in one direction, allowing it to operate under compression * Snow chains, used to improve traction in snow

Weapons

* Chain gun, type of machine gun that is driven by an external power source, sometimes connected by a chain, to actuate the mechanism rather than using recoil *

Chain shot In artillery, chain shot is a type of cannon projectile formed of two sub-calibre balls, or half-balls, chained together. Bar shot is similar, but joined by a solid bar. They were used in the age of sailing ships and black powder cannon to s ...

, a type of ammunition for a

cannon A cannon is a large-caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder during th ...

, used to inflict damage to the

rigging Rigging comprises the system of ropes, cables and chains, which support and control a sailing ship or sail boat's masts and sails. ''Standing rigging'' is the fixed rigging that supports masts including shrouds and stays. ''Running rigg ...

of a sail vessel in

naval warfare Naval warfare is combat in and on the sea, the ocean, or any other battlespace involving a major body of water such as a large lake or wide river. The Military, armed forces branch designated for naval warfare is a navy. Naval operations can be ...

* Chain weapon, a medieval weapon made of one or more weights attached to a handle with a chain

Other uses

* Chains are a standard component of the deflection assembly of disc golf baskets. * Chains can be used as a

percussion instrument A percussion instrument is a musical instrument that is sounded by being struck or scraped by a percussion mallet, beater including attached or enclosed beaters or Rattle (percussion beater), rattles struck, scraped or rubbed by hand or ...

for special effects, such as in

Arnold Schoenberg Arnold Schoenberg or Schönberg (13 September 187413 July 1951) was an Austrian and American composer, music theorist, teacher and writer. He was among the first Modernism (music), modernists who transformed the practice of harmony in 20th-centu ...

's ''

Gurre-Lieder ' (''Songs of Gurre Castle, Gurre'') is a tripartite oratorio followed by a Melodrama, melodramatic epilogue for five vocal soloists, narrator, three choruses, and grand orchestra. The work, which is based on an early song cycle for soprano, te ...

'' and

Leoš Janáček Leoš Janáček (, 3 July 1854 – 12 August 1928) was a Czech composer, Music theory, music theorist, Folkloristics, folklorist, publicist, and teacher. He was inspired by Moravian folk music, Moravian and other Slavs, Slavic music, includin ...

's '' From the House of the Dead''. *

Keychain A keychain () (also keyring) is a small ring or chain of metal to which several keys, or fobs can be attached. The terms keyring and keychain are often used interchangeably to mean both the individual ring, or a combined unit of a ring and fob ...

, a small chain that connects a small item to a keyring *

Chain sinnet A chain sinnet (or chain sennit) is a method of shortening a rope or other Wire rope, cable while in use or for storage. It is formed by making a series of simple crochet-like stitches in the line.Clifford W. Ashley, ''The Ashley Book of Knots ...

, a method of shortening a rope or other cable while in use or for storage *

Chain stitch Chain stitch is a sewing and embroidery technique in which a series of looped stitches form a chain-like pattern. Chain stitch is an ancient craft – examples of surviving Chinese chain stitch embroidery worked in silk thread have been dat ...

, a sewing and embroidery technique * Chains were introduced by

Chanel Chanel ( , ) is a French luxury fashion house founded in 1910 by Coco Chanel in Paris. It is privately owned by French brothers, Alain and Gérard Wertheimer, through the holding company Chanel Limited, established in 2018 and headquarte ...

weight In science and engineering, the weight of an object is a quantity associated with the gravitational force exerted on the object by other objects in its environment, although there is some variation and debate as to the exact definition. Some sta ...

s in clothes, to improve their overall look. 1965 Chanel suit and silk blouse detail2

Types of chain

* Ball chain, type of chain consisting of small sheet metal balls connected via short lengths of wire * Calibrated chain, a type chain where the link lengths are within a given tolerance, so that it reliably engages with a

windlass The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound arou ...

. * Flat chain, form of chain used chiefly in agricultural machinery * Ladder chain, a light wire chain used with sprockets for low torque power transmission * Long link chain * O-ring chain, a specialized type of roller chain *

Roller chain Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, pr ...

, the type of chain most commonly used for transmission of mechanical power on bicycles, motorcycles, and in industrial and agricultural machinery *

Self-lubricating chain Self-lubricating chains, also referred to as lube-free chains, are commonly found in both roller chain (American National Standards Institute, ANSI Standards, British Standards, and Deutsches Institut für Normung, DIN Standards) and conveyor chain ...

, type of chain that uses a bush to continually lubricate the chain * Silent chain, a type of chain in which the links engage the sprockets similarly to gear teeth * Stud link chain, a type of chain with metal between the sides of each link, keeping the attached links in place. This helps prevent bunching when the chain is run out from a storage bin, as for use in anchoring ships. * Short link chain, a chain where the gap between attached links is small relative to thickness.

Connections

Several methods are available to connect chain ends to each other or to other objects, and to apply a load to a chain away from the ends. These methods are usually specific to the type of chain, and must be of the correct size.

Invention

The metal link chain has been in use since at least 225 BC.As early as 225 BC, chain was used to draw a bucket of water up from a well. This very early bucket chain was composed of connected metal rings.

Symbolism

The prevalent modern symbolism is

oppression Oppression is malicious or unjust treatment of, or exercise of power over, a group of individuals, often in the form of governmental authority. Oppression may be overt or covert, depending on how it is practiced. No universally accepted model ...

, due to the use for a mechanical restriction of the

liberty Liberty is the state of being free within society from oppressive restrictions imposed by authority on one's way of life, behavior, or political views. The concept of liberty can vary depending on perspective and context. In the Constitutional ...

of a human or animal. Chains can also symbolize interconnectivity or

interdependence Systems theory is the transdisciplinary study of systems, i.e. cohesive groups of interrelated, interdependent components that can be natural or artificial. Every system has causal boundaries, is influenced by its context, defined by its structur ...

Unicode Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Char ...

, in versions 6.x, contains the , which may show chain link(s). It may also denote a

hyperlink In computing, a hyperlink, or simply a link, is a digital reference providing direct access to Data (computing), data by a user (computing), user's point and click, clicking or touchscreen, tapping. A hyperlink points to a whole document or to ...

Gallery

File:Silent chain.jpg, Silent chain File:Rope chain.jpg, Rope chain File:Twisted link chain.jpg, Twisted link chain File:Wheat chain.jpg, Wheat chain File:Single-jack-chain.jpg, Single jack chain File:Double jack chain.jpg, Double jack chain File:Studlink chain link.jpg, Stud link chain File:Ladder link chain.jpg, Ladder link chain File:Foxtail chain.jpg, Foxtail chain File:Rolo chain.jpg, Rolo chain File:BikeChain.png, Bike Chain

References

External links

National Association of Chain Manufacturers
NACM Welded Steel Chain Specifications
Chain Grades and Links Explained
Jamestown Distributors * {{Authority control