Pliers are a hand tool used to hold objects firmly, possibly developed from

tongs Tongs are a type of tool used to grip and lift objects instead of holding them directly with hands. There are many forms of tongs adapted to their specific use. The first pair of tongs belongs to the Egyptians. Tongs likely started off as ...

used to handle hot metal in

Bronze Age The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second prin ...

Europe. They are also useful for

bending In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element. The structural element is assumed to ...

and physically compressing a wide range of materials. Generally, pliers consist of a pair of

metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...

first-class levers joined at a

fulcrum A fulcrum is the support about which a lever pivots. Fulcrum may also refer to: Companies and organizations * Fulcrum (Anglican think tank), a Church of England think tank * Fulcrum Press, a British publisher of poetry * Fulcrum Wheels, a bicy ...

positioned closer to one end of the levers, creating short ''jaws'' on one side of the fulcrum, and longer

handles A handle is a part of, or attachment to, an object that allows it to be grasped and manipulated by hand. The design of each type of handle involves substantial ergonomic issues, even where these are dealt with intuitively or by following t ...

on the other side. This arrangement creates a

mechanical advantage Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for ...

, allowing the force of the

grip strength Grip strength is the force applied by the hand to pull on or suspend from objects and is a specific part of hand strength. Optimum-sized objects permit the hand to wrap around a cylindrical shape with a diameter from one to three inches. Stair rai ...

to be amplified and focused on an object with precision. The jaws can also be used to manipulate objects too small or unwieldy to be manipulated with the

finger A finger is a limb of the body and a type of digit, an organ of manipulation and sensation found in the hands of most of the Tetrapods, so also with humans and other primates. Most land vertebrates have five fingers ( Pentadactyly). Chambers ...

s. Diagonal pliers, also called side cutters, are a similarly-shaped tool used for cutting rather than holding, having a pair of stout blades, similar to scissors except that the cutting surfaces meet parallel to each other rather than overlapping. Ordinary (holding/squeezing) pliers may incorporate a small pair of such cutting blades. Pincers are a similar tool with a different type of head used for cutting and pulling, rather than squeezing. Tools designed for safely handling hot objects are usually called tongs. Special tools for making

crimp connection An electrical crimp is a type of solderless electrical connection. Crimp connectors are typically used to terminate stranded wire. The benefits of crimping over soldering and wire wrapping include: * A well-engineered and well-executed crimp is ...

s in electrical and electronic applications are often called crimping pliers or crimpers; each type of connection uses its own dedicated tool. There are many kinds of pliers made for various general and specific purposes.

History

As pliers in the general sense are an ancient and simple invention, no single inventor can be credited. Early metal working processes from several millennia

BCE Common Era (CE) and Before the Common Era (BCE) are year notations for the Gregorian calendar (and its predecessor, the Julian calendar), the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the or ...

would have required plier-like devices to handle hot materials in the process of

smithing A metalsmith or simply smith is a craftsperson fashioning useful items (for example, tools, kitchenware, tableware, jewelry, armor and weapons) out of various metals. Smithing is one of the oldest metalworking occupations. Shaping metal with a h ...

casting Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a ''casting'', which is ejected ...

. Development from

wooden Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin tha ...

to bronze pliers would have probably happened sometime prior to

3000 BCE The 30th century BC was a century that lasted from the year 3000 BC to 2901 BC. Events * Before 3000 BC: An image of a deity (detail from a cong) recovered from Tomb 12 in Fanshan, Yuyao, Zhejiang, is made during the Neolithic period by the Li ...

. Among the oldest illustrations of pliers are those showing the

Greek god The following is a list of gods, goddesses, and many other divine and semi-divine figures from ancient Greek mythology and ancient Greek religion. Immortals The Greeks created images of their deities for many purposes. A temple would house the ...

Hephaestus Hephaestus (; eight spellings; grc-gre, Ἥφαιστος, Hḗphaistos) is the Greek god of blacksmiths, metalworking, carpenters, craftsmen, artisans, sculptors, metallurgy, fire (compare, however, with Hestia), and volcanoes.Walter B ...

in his forge. The number of different designs of pliers grew with the invention of the different objects which they were used to handle: horseshoes,

fasteners A fastener (US English) or fastening (UK English) is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or disman ...

wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...

pipe Pipe(s), PIPE(S) or piping may refer to: Objects * Pipe (fluid conveyance), a hollow cylinder following certain dimension rules ** Piping, the use of pipes in industry * Smoking pipe ** Tobacco pipe * Half-pipe and quarter pipe, semi-circular ...

electrical Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described ...

, and electronic components.

Design

The basic design of pliers has changed little since their origins, with the pair of ''handles'', the ''pivot'' (often formed by a

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

), and the ''head'' section with the gripping jaws or cutting edges forming the three elements. The materials used to make pliers consist mainly of steel

alloy An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductilit ...

s with additives such as vanadium or chromium, to improve strength and prevent

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engi ...

. The metal handles of pliers are often fitted with grips of other materials to ensure better handling; grips are usually insulated and additionally protect against electric shock. The jaws vary widely in size, from delicate

needle-nose pliers Needle-nose pliers, also known as long-nose pliers and snipe-nose pliers, are both cutting and holding pliers used by artisans, jewellery designers, electricians, network engineers and other tradesmen to bend, re-position and snip wire. Their name ...

to heavy jaws capable of exerting much pressure, and shape, from basic flat jaws to various specialized and often asymmetrical jaw configurations for specific manipulations. The surfaces are typically textured rather than smooth, to minimize slipping. A plier-like tool designed for cutting

s is often called

diagonal pliers Diagonal pliers (also known as wire cutters, diagonal cutting pliers, diagonal cutters, side cutters, dikes or Nippy cutters) are pliers intended for the cutting of wire (they are generally not used to grab or turn anything). The plane defi ...

. Some pliers for electrical work are fitted with wire-cutter blades either built into the jaws or on the handles just below the pivot. Where it is necessary to avoid scratching or damaging the workpiece, as for example in

jewellery Jewellery ( UK) or jewelry (U.S.) consists of decorative items worn for personal adornment, such as brooches, rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the clothes. From a wester ...

and musical instrument

repair The technical meaning of maintenance involves functional checks, servicing, repairing or replacing of necessary devices, equipment, machinery, building infrastructure, and supporting utilities in industrial, business, and residential installa ...

, pliers with a layer of softer material such as

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

brass Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other wit ...

, or

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

over the jaws are used.

Ergonomics

Much research has been undertaken to improve the design of pliers, to make them easier to use in often difficult circumstances (such as restricted spaces). The handles can be bent, for example, so that the load applied by the hand is aligned with the arm, rather than at an angle, thus reducing

muscle fatigue Muscle fatigue is the decline in ability of muscles to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main ca ...

. It is especially important for factory workers who use pliers continuously and helps prevent

carpal tunnel syndrome Carpal tunnel syndrome (CTS) is the collection of symptoms and signs associated with median neuropathy at the carpal tunnel. Most CTS is related to idiopathic An idiopathic disease is any disease with an unknown cause or mechanism of apparen ...

Types

Image:Pliers slip 01CJC.png,

Slip joint pliers Slip joint pliers are pliers whose pivot point or fulcrum A fulcrum is the support about which a lever pivots. Fulcrum may also refer to: Companies and organizations * Fulcrum (Anglican think tank), a Church of England think tank * Fulcrum Pr ...

Image:Side cutters.jpg,

Diagonal pliers Diagonal pliers (also known as wire cutters, diagonal cutting pliers, diagonal cutters, side cutters, dikes or Nippy cutters) are pliers intended for the cutting of wire (they are generally not used to grab or turn anything). The plane defi ...

or side cutters File:Klein lineman's pliers.jpg,

Lineman's pliers Lineman's pliers (US English), Kleins (genericized trademark, US usage), linesman pliers (Canadian English), side cutting linesman pliers and combination pliers (UK / US English) are a type of pliers used by Lineworker, linemen, electricians, and o ...

or combination pliers Image:Long-nosePliers.jpg,

Needle-nose pliers Needle-nose pliers, also known as long-nose pliers and snipe-nose pliers, are both cutting and holding pliers used by artisans, jewellery designers, electricians, network engineers and other tradesmen to bend, re-position and snip wire. Their name ...

File:Small green bent nose pliers - D.jpg, Bent nose pliers File:Pincers.jpg,

Pincer Pincer may refer to: * Pincers (tool) *Pincer (biology), part of an animal *Pincer ligand In chemistry, a transition metal pincer complex is a type of coordination complex with a pincer ligand. Pincer ligands are chelating agents that binds tig ...

s Image:Pliers crimp 01CJC.png, Electrical wire stripping and terminal crimping pliers Image:Crimper HDF200.jpg, Crimptool for N, R-SMA, TNC connectors for RG174, RG58 and HDF/LMR200 Image:Crimping-pliers-pro-RJ-0a.jpg, Heavy duty crimping pliers for

modular connector A modular connector is a type of electrical connector for cords and cables of electronic devices and appliances, such as in computer networking, telecommunication equipment, and audio headsets. Modular connectors were originally developed fo ...

that have interchangeable RJ heads Image:Hand crimp tool MH-17 opening.jpg, Hand crimp tool Image:Multiple pliers.jpg,

Tongue-and-groove pliers Tongue-and-groove pliers are a type of slip-joint pliers. They are also known as: * adjustable pliers, * Channellocks ( i.e., Channellock brand pliers), * water pump pliers, * groove-joint pliers, * arc-joint pliers, * Multi-Grips, * tap or pipe ...

, also known as channel-locks after the Channellock brand Image:Locking pliers.jpg,

Locking pliers Locking pliers (also called Vise-Grips, a vice grip, Mole wrench or mole grips) are pliers that can be locked into position, using an "over-center" cam action. Locking pliers are available with many different jaw styles, such as needle-nose pli ...

, also known as a vise-grip Image:Retaining ring pliers.jpg,

Circlip A circlip (a portmanteau of "circle" and "clip"), also known as a C-clip, Rotor Clip, snap ring or Jesus clip, is a type of fastener or retaining ring consisting of a semi-flexible metal ring with open ends which can be snapped into place, int ...

pliers, for fitting and removing

retaining ring A retaining ring is a fastener that holds components or assemblies onto a shaft or in a housing/bore when installed - typically in a groove - for one time use only. Once installed, the exposed portion acts as a shoulder which retains the speci ...

s Image:Klieste na segerove poistky.jpg, Round-nose pliers, for making loops in wires File:Wiper pliers.jpg, Wiper pliers used to adjust the wipers and spring-sets on electro-mechanical relays. File:Knipex_Pliers_Wrench_type_86.jpg, Contemporary 'Pliers Wrench' with high mechanical advantage parallel-gripping jaws.

References

External links