A
detonator is a device used to
triggerDetonation involves a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations are observed in both conventional solid and liquid explosives, as well as in reactive gases...
an
explosive deviceAn explosive device is device that relies on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy. Explosive devices have applications as demolition devices and as weapons in the military....
. Detonators can be chemically, mechanically, or electrically initiated, the latter two being the most common.
The commercial use of explosives uses electrical detonators or the capped fuse which is a length of safety
fuseIn an explosive, pyrotechnic device or military munition, a fuse is the part of the device that initiates function. In common usage, the word fuse is used indiscriminately...
to which an ordinary detonator has been
crimpCrimping is joining two pieces of metal or other malleable material by deforming one or both of them to hold the other. The bend or deformity is called the crimp.- Uses :...
ed. Many detonators' primary explosive is a material called ASA compound. This compound is formed from lead azide,
lead styphnateLead styphnate , whose name is derived from styphnic acid, is an explosive used as a component in primer and detonator mixtures for less sensitive secondary explosives....
and
aluminiumAluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
and is pressed into place above the base charge, usually
TNT or
tetryl2,4,6-Trinitrophenylmethylnitramine commonly referred to as tetryl is a sensitive explosive compound used to make detonators and explosive booster charges....
in military detonators and
PETNPentaerythritol tetranitrate , also known as PENT, PENTA, TEN, corpent, penthrite , is the nitrate ester of pentaerythritol. Penta refers to the five carbon atoms of the neopentane skeleton.PETN is most well known as an explosive...
in commercial detonators.
Other materials such as DDNP (
diazo dinitro phenolDiazodinitrophenol is a yellowish brown powder. It is soluble in acetic acid, acetone, concentrated hydrochloric acid, and most non-polar solvents but is insoluble in water....
) are also used as the primary charge to reduce the amount of lead emitted into the atmosphere by
miningMining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
and
quarryA quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...
ing operations. Old detonators used mercury fulminate as the primary, and it was often mixed with
potassium chloratePotassium chlorate is a compound containing potassium, chlorine and oxygen atoms, with the molecular formula KClO3. In its pure form, it is a white crystalline substance. It is the most common chlorate in industrial use...
to yield better performance.
Electrical detonators
There are three categories of electrical detonators:
instantaneous electrical detonators (
IED),
short period delay detonators (
SPD) and
long period delay detonators (
LPD). SPDs are measured in milliseconds and LPDs are measured in seconds.
In situations where nanosecond accuracy is required, specifically in the implosion charges in
nuclear weaponA nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s,
exploding-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...
s are employed. The initial shock wave is created by vaporizing a length of a thin wire by an
electric dischargeElectric discharge describes any flow of electric charge through a gas, liquid or solid. Electric discharges include:*Electric glow discharge*Electric arc*Electrostatic discharge*Electric discharge in gases*Leader *Partial discharge...
.
A new development is a
slapper detonatorA slapper detonator, also called exploding foil initiator , is a relatively recent kind of a detonator developed in Lawrence Livermore National Laboratory...
, which uses thin plates accelerated by an electrically exploded wire or foil to deliver the initial shock. It is in use in some modern weapon systems. A variant of this concept is used in mining operations, when the foil is exploded by a
laserA laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
pulse delivered to the foil by
optical fiberAn optical fiber is a flexible, transparent fiber made of a pure glass not much wider than a human hair. It functions as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. The field of applied science and engineering concerned with the design and application of...
.
Electronic detonators
In civil mining, electronic detonators (Daveytronic) have a better precision for delays.
Non-electric detonators
Non-electric detonators usually take the form of an ignition-based explosive. Whilst they are mainly used in commercial operations, non-electric detonators are still used in military operations. This form of detonator is most commonly initiated using
safety fuseThe safety fuse is a type of fuse invented and patented by William Bickford in 1831. Originally it consisted of a "tube" of gunpowder surrounded by a water-proofed varnished jute "rope". It replaced earlier and less reliable methods of igniting gunpowder blasting charges which had caused many...
, and used in non time-critical detonations i.e. Conventional Munitions Disposal
Fictional variations
- Ion detonator, in the video game Destroy All Humans!
- Mk2 detonator, in the video game GoldenEye: Rogue Agent
- Thermal detonator, in the film series Star Wars
See also
- Blasting cap
A 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....
- Detonation
Detonation involves a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations are observed in both conventional solid and liquid explosives, as well as in reactive gases...
- Detonating cord
Detonating cord is a thin, flexible plastic tube filled with PETN . With the PETN exploding at a rate of approximately 4 miles per second, any common length of det cord appears to explode instantaneously...
- Detonator (railway)
A railway detonator is a device used to make a loud sound as a warning signal to train drivers. The detonator is the size of a large coin with two lead straps, one on each side. The detonator is placed on the top of the rail and the straps are used to secure it...
- Exploding-bridgewire detonator
The 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...
- Explosive booster
An explosive booster acts as a bridge between a low energy explosive and a low sensitivity explosive such as TNT. It increases the explosive shockwave from an initiating explosive to the degree sufficient to detonate the secondary charge.Unlike C4 plastic explosive, not all explosives can be...
- Explosive material
An explosive material, also called an explosive, is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure...
- Firing pin
A firing pin or striker is part of the firing mechanism used in a firearm or explosive device e.g. an M14 landmine or bomb fuze. Firing pins may take many forms, though the types used in landmines, bombs, grenade fuzes or other single-use devices generally have a sharpened point...
- Fuse (explosives)
In an explosive, pyrotechnic device or military munition, a fuse is the part of the device that initiates function. In common usage, the word fuse is used indiscriminately...
- NASA standard detonator
The NASA Standard Detonator is a device used by NASA for applications where a charge must be detonated, usually in conjunction with frangible nuts as a release mechanism. NSDs have been used since the Gemini program, and were used for the Space Shuttle program, including the Solid Rocket Booster ...
- Nuclear weapon design
Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three basic design types...
- Pencil detonator
A pencil detonator or time pencil is a time fuze designed to be connected to a detonator or short length of safety fuse. They are about the same size and shape as a pencil, hence the name. They were introduced during World War II.- No. 10 delay switch :...
- Shock tube detonator
Shock tube detonator is a non-electric explosive fuze or initiator in the form of small-diameter hollow plastic tubing used to transport an initiating signal to an explosive charge by means of a percussive wave traveling the length of the tube...
- Slapper detonator
A slapper detonator, also called exploding foil initiator , is a relatively recent kind of a detonator developed in Lawrence Livermore National Laboratory...
- Triggering sequence
A triggering sequence, also called an explosive train, is a sequence of events that culminates in the detonation of explosives. For safety reasons, most widely used high explosives are difficult to detonate. A primary explosive of higher sensitivity is used to trigger a uniform and predictable...
- Urchin (detonator)
A modulated neutron initiator is a neutron source capable of producing a burst of neutrons on activation. It is a crucial part of some nuclear weapons, as its role is to "kick-start" the chain reaction at the optimal moment when the configuration is prompt critical. It is also known as an internal...