Electric match
Encyclopedia
An electric match is a device that uses an externally applied electric current
to ignite a combustible compound.
and a pyrogen. The bridgewire is a heating element
, typically in the form of a loop or coil of thin wire, which is encased in the pyrogen, which is a quantity of readily ignited pyrotechnic initiator
composition. If the pyrogen is sufficiently conductive, it can act as the bridgewire as well. Electric matches also come with provisions for attaching an electric current source, and they may be provided with a protective cover and/or a means to attach them to the device to be ignited.
To operate an electric match, a source of electricity of appropriate voltage and current is needed to provide current to the match. When sufficient electric current
is passed through the bridgewire, the resistive heating
causes the element to rise above the ignition temperature of the pyrogen, and the pyrogen begins to burn.
and propane
fueled commercial and household appliances and amenities. Some examples are gas stoves and barbecue
s, interior and swimming pool
hot water heaters and boiler
s, fireplace
s and garden fire pits
, and clothes dryer
s and central heating systems.
wire, along with components for mixing the pyrogen. Scratch-built matches use thin wire which may be purchased or salvaged from sources such as light bulb filaments, and copper
wiring.
motors often include powdered metals, which provide more heat and duration to the match flame, and a more reliable ignition of the motor.
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...
to ignite a combustible compound.
Use
Electric matches can be used in any application where source of heat is needed at a precisely controlled point in time, typically to ignite a propellant or explosive. A partial list of applications is:- AirbagAirbagAn Airbag is a vehicle safety device. It is an occupant restraint consisting of a flexible envelope designed to inflate rapidly during an automobile collision, to prevent occupants from striking interior objects such as the steering wheel or a window...
deployment - PyrotechnicsPyrotechnicsPyrotechnics is the science of using materials capable of undergoing self-contained and self-sustained exothermic chemical reactions for the production of heat, light, gas, smoke and/or sound...
- Military or commercial explosives
- Model rocketModel rocketA model rocket is a small rocket that is commonly advertised as being able to be launched by anybody, to, in general, low altitudes and recovered by a variety of means....
ry - FireplaceFireplaceA fireplace is an architectural structure to contain a fire for heating and, especially historically, for cooking. A fire is contained in a firebox or firepit; a chimney or other flue allows gas and particulate exhaust to escape...
s - natural gasNatural gasNatural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
-propanePropanePropane is a three-carbon alkane with the molecular formula , normally a gas, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel for engines, oxy-gas torches, barbecues, portable stoves, and residential central... - Gas stoveGas stoveIn cooking, a gas stove is a cooker which uses natural gas, propane, butane, liquefied petroleum gas or other flammable gas as a fuel source.-History:...
s and barbecueBarbecueBarbecue or barbeque , used chiefly in the United States, Canada, the United Kingdom, New Zealand and Australia is a method and apparatus for cooking meat, poultry and occasionally fish with the heat and hot smoke of a fire, smoking wood, or hot coals of...
s
Construction and operation
Electric matches consist of two parts, a bridgewireBridgewire
A bridgewire, bridge wire, or hot bridge wire is a relatively thin resistance wire used to set off a pyrotechnic composition serving as pyrotechnic initiator. By passing of electric current it is heated to a high temperature that starts the exothermic chemical reaction of the attached composition...
and a pyrogen. The bridgewire is a heating element
Heating element
A heating element converts electricity into heat through the process of Joule heating. Electric current through the element encounters resistance, resulting in heating of the element....
, typically in the form of a loop or coil of thin wire, which is encased in the pyrogen, which is a quantity of readily ignited pyrotechnic initiator
Pyrotechnic initiator
A pyrotechnic initiator is a device containing a pyrotechnic composition used primarily to ignite other, more difficult-to-ignite materials, e.g. thermites, gas generators, and solid-fuel rockets...
composition. If the pyrogen is sufficiently conductive, it can act as the bridgewire as well. Electric matches also come with provisions for attaching an electric current source, and they may be provided with a protective cover and/or a means to attach them to the device to be ignited.
To operate an electric match, a source of electricity of appropriate voltage and current is needed to provide current to the match. When sufficient electric current
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...
is passed through the bridgewire, the resistive heating
Joule heating
Joule heating, also known as ohmic heating and resistive heating, is the process by which the passage of an electric current through a conductor releases heat. It was first studied by James Prescott Joule in 1841. Joule immersed a length of wire in a fixed mass of water and measured the temperature...
causes the element to rise above the ignition temperature of the pyrogen, and the pyrogen begins to burn.
Appliances and amenities
Electric matches, or electronic ignition, is used in natural gasNatural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
and propane
Propane
Propane is a three-carbon alkane with the molecular formula , normally a gas, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel for engines, oxy-gas torches, barbecues, portable stoves, and residential central...
fueled commercial and household appliances and amenities. Some examples are gas stoves and barbecue
Barbecue
Barbecue or barbeque , used chiefly in the United States, Canada, the United Kingdom, New Zealand and Australia is a method and apparatus for cooking meat, poultry and occasionally fish with the heat and hot smoke of a fire, smoking wood, or hot coals of...
s, interior and swimming pool
Swimming pool
A swimming pool, swimming bath, wading pool, or simply a pool, is a container filled with water intended for swimming or water-based recreation. There are many standard sizes; the largest is the Olympic-size swimming pool...
hot water heaters and boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
s, fireplace
Fireplace
A fireplace is an architectural structure to contain a fire for heating and, especially historically, for cooking. A fire is contained in a firebox or firepit; a chimney or other flue allows gas and particulate exhaust to escape...
s and garden fire pits
Outdoor fireplace
An outdoor fireplace is a place for building fires outside of the home. Similar in construction to an indoor fireplace, an outdoor fireplace is usually added to a stone, brick, or concrete patio. It often consists of a firebox and a chimney. As with indoor fireplaces, an outdoor fireplace...
, and clothes dryer
Clothes dryer
A clothes dryer or tumble dryer is a household appliance that is used to remove moisture from a load of clothing and other textiles, generally shortly after they are cleaned in a washing machine....
s and central heating systems.
Pyrotechnics
Electric matches may be regulated, as they can be used to ignite explosives; for amateur pyrotechnics use, electric matches can be built from scratch or from kit form. Kits include the thin wire needed for the bridgewire, such as nichromeNichrome
Nichrome is a non-magnetic alloy of nickel, chromium, and often iron, usually used as a resistance wire. Patented in 1905, it is the oldest documented form of resistance heating alloy. A common alloy is 80% nickel and 20% chromium, by mass, but there are many others to accommodate various...
wire, along with components for mixing the pyrogen. Scratch-built matches use thin wire which may be purchased or salvaged from sources such as light bulb filaments, and copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
wiring.
Model rockets
In addition to the readily ignitable component of the electric match pyrogen, some matches may also add additional components to provide a hotter, longer lasting flame, for igniting items that are difficult to ignite. For example, igniters for solid fuel model rocketModel rocket
A model rocket is a small rocket that is commonly advertised as being able to be launched by anybody, to, in general, low altitudes and recovered by a variety of means....
motors often include powdered metals, which provide more heat and duration to the match flame, and a more reliable ignition of the motor.
See also
- Tubes and primers for ammunitionTubes and primers for ammunitionTubes and primers are used to ignite the propellant in projectile weapons.In ancient times various devices were adopted to ignite the charge. Small guns were fired by priming powder poured down the touch hole and ignited by glowing embers or a red-hot iron rod. Later the priming powder was...
- PrimersPercussion capThe percussion cap, introduced around 1830, was the crucial invention that enabled muzzleloading firearms to fire reliably in any weather.Before this development, firearms used flintlock ignition systems which produced flint-on-steel sparks to ignite a pan of priming powder and thereby fire the...
- Blasting capBlasting capA blasting cap is a small sensitive primary explosive device generally used to detonate a larger, more powerful and less sensitive secondary explosive such as TNT, dynamite, or plastic explosive....
- Micro combined heat and power
- Renewable natural gasRenewable natural gasRenewable natural gas, also known as sustainable natural gas, is a biogas which has been upgraded to a quality similar to fossil natural gas. A biogas is a gas methane obtained from biomass. By upgrading the quality to that of natural gas, it becomes possible to distribute the gas to customers via...
- Squib (explosive)Squib (explosive)A squib is a miniature explosive device used in a wide range of industries, from special effects to military applications. It resembles a tiny stick of dynamite, both in appearance and construction, although with considerably less explosive power...
- Pyrotechnic fastenerPyrotechnic fastenerA pyrotechnic fastener is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt are typically activated by an electric current, and the charge breaks the bolt into two or more pieces...
- Exploding-bridgewire detonatorExploding-bridgewire detonatorThe exploding-bridgewire detonator is a type of detonator used to initiate the detonation reaction in explosive materials, similar to a blasting cap in that it is fired using an electric current...