'Pliers' are hand
tools, designed primarily for gripping objects by using
leverage. Pliers are designed for numerous purposes and require different jaw configurations to grip, turn, pull, or crimp a variety of things. They are a tool common to many dexterous trades and occupations. Many types of pliers also include jaws for cutting.
History
Pliers were invented in
Europe around
2000 BC to grip hot objects (principally
iron as it was being forged on an
anvil). Among the oldest illustrations of pliers are those showing the
Greek god
Hephaestus in his smithy. Today, pliers intended principally to be used for safely handling hot objects are usually called
tongs. The number of different designs of pliers grew with the invention of the different objects which they were used to handle:
horse shoes,
fasteners,
wire,
pipes,
electrical 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), and the ''head'' section with the gripping jaws or cutting edges forming the three elements. In distinction to a pair of
scissors or
shears, the plier's jaws always meet each other at one point.
Pliers are an instrument that convert a power grip - the curling of the fingers into the palm of the hand - into a precision grip, directing the power of the hand's grip in a precise fashion on to the object(s) to be gripped. The handles are long relative to the shorter nose of the pliers. The two arms thus act as first class
levers with a
mechanical advantage, increasing the
force applied by the hand's grip and concentrating it on the work piece.
The materials used to make pliers consist mainly of
steel alloys with additives such as
Vanadium and/or
Chromium, to improve alloy strength and prevent corrosion. Often pliers have insulated grips to ensure better handling and prevent electrical conductivity.
Common types

Lock jaw pliers, also called ''vise grips'' or "mole grips".
NOTE: Vise-Grip is a trade name of IRWIN Industrial Tools pliers
Gripping pliers (used to improve grip)
★ Combination pliers or
lineman's pliers
★ Flat nose pliers, also known as "duckbill," after their resemblance to a duck's bill. With long, narrow, flat jaws, they are stronger than long-nose (needle-nose) pliers, but less able to reach into really confined spaces
★ Round nose pliers, sometimes called snub-nosed pliers
★ Long-nose or
needle-nose pliers, which have long, narrow jaws for gripping in confined spaces
★ Groove joint or tongue & groove pliers (occasionally called water pump pliers although technically water pump pliers are a
slip joint plier in the general configuration of groove joint pliers; or referred to by the name of a well-known manufacturer,
Channellock) - with adjustable jaw sizes, which are designed to grip various sizes of round, hexagon, flat or similarly shaped objects
★ Retaining ring or circlip pliers, which are used for fixing or loosening retaining rings
★ Locking pliers
★ Nail pulling pliers - an adaptation of the end nipper used for cutting wire; the jaws may be asymmetric, allowing the nail to be pulled out with a rocking motion on the surface in which it is imbedded.
★ Glass Breaking / Grozz Pliers (
Breaker-grozier pliers).
Cutting pliers (used to sever or pinch off)
★ Combination pliers or
lineman's pliers
★
Diagonal pliers (wire cutters, side cutting pliers or side cutters) not really pliers as it is only used for cutting
★ Pinching pliers (end nippers)
★ Wire stripping pliers - cuts and removes insulation on electrical wire while leaving the wire intact
★ Needle-nose pliers - designed for gripping, but typically incorporate a cutter for 'one-tool' convenience.
===
Crimping pliers ===
★ For crimping electrical terminals and
connectors (solderless connections)
★ For crimping metal rings or tags on livestock
★ For crimping metal security seals on cargo carriers
★ For crimping an impression on a document - as in a notary's seal
★ For crimping laboratory vials
★ For crimping bottles with sprayer tops, such as perfume bottles
Rotational pliers
★ developed by NASA engineers to enable an astronaut to turn a nut in zero gravity. The clamping motion of the hand is converted to rotational motion to drive a socket wrench
See also