Torpex
Encyclopedia
Torpex is a secondary explosive 50% more powerful than TNT by mass. Torpex is composed of 42% RDX
, 40% TNT and 18% powdered
aluminium
. It was used in the Second World War from late 1942. The name is short for 'Torpedo Explosive', having been originally developed for use in torpedo
es. Torpex proved to be particularly useful in underwater munitions because the aluminium component had the effect of making the explosive pulse last longer, which enhanced the destructive power. Torpex was used only in critical applications, e.g. torpedoes and the Upkeep
, Tallboy
and Grand Slam
bombs. It was also used in the Operation Aphrodite
drones. Torpex has long been superseded by H6
and PBX
compositions. It is therefore regarded as obsolete, so Torpex is unlikely to be encountered except in the form of legacy munitions or unexploded ordnance
.
, in the United Kingdom
as a more powerful military alternative to TNT. RDX
was developed in 1899. Though very stable and serving as the reference point by which the sensitivity of other explosives are judged, it was too expensive for most military applications, and reserved for use in the most important products, such as torpedoes. Aluminium powder was also added to the mix to further enhance the effect. Although both RDX and TNT have a negative oxygen balance (RDX would require 9 oxygen atoms to oxidize all of its carbon and hydrogen but has only 6, while 2 molecules of TNT together would need 33 oxygen molecules but have only 12). However the aluminum powder is superheated by the explosion and combines with environmental oxygen in a highly exothermic reaction which generates additional heat and thus greater explosive product volume and expansive force. This produces a longer and more damaging explosive pulse than high explosive alone in a process similar to a thermobaric weapon. Beeswax
was also added to reduce sensitivity to shock and impact. Later, beeswax was replaced with a petroleum
-based product, and calcium carbonate
was added as a moisture absorber to reduce the production of hydrogen
gas under high humidity.
RDX
RDX, an initialism for Research Department Explosive, is an explosive nitroamine widely used in military and industrial applications. It was developed as an explosive which was more powerful than TNT, and it saw wide use in WWII. RDX is also known as cyclonite, hexogen , and T4...
, 40% TNT and 18% powdered
Powder (substance)
A powder is a dry,thick bulk solid composed of a large number of very fine particles that may flow freely when shaken or tilted. Powders are a special sub-class of granular materials, although the terms powder and granular are sometimes used to distinguish separate classes of material...
aluminium
Aluminium
Aluminium 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....
. It was used in the Second World War from late 1942. The name is short for 'Torpedo Explosive', having been originally developed for use in torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
es. Torpex proved to be particularly useful in underwater munitions because the aluminium component had the effect of making the explosive pulse last longer, which enhanced the destructive power. Torpex was used only in critical applications, e.g. torpedoes and the Upkeep
Bouncing bomb
A bouncing bomb is a bomb designed specifically to bounce to a target across water in a calculated manner, in order to avoid obstacles such as torpedo nets, and to allow both the bomb's speed on arrival at the target and the timing of its detonation to be pre-determined...
, Tallboy
Tallboy bomb
The Tallboy or Bomb, Medium Capacity, 12,000 lb, was an earthquake bomb developed by the British aeronautical engineer Barnes Wallis and deployed by the RAF in 1944...
and Grand Slam
Grand Slam bomb
The Grand Slam was a 22,000 lb earthquake bomb used by RAF Bomber Command against strategic targets during the Second World War.Known officially as the Bomb, Medium Capacity, 22,000 lb, it was a scaled up version of the Tallboy bomb and closer to the original size that the bombs' inventor,...
bombs. It was also used in the Operation Aphrodite
Operation Aphrodite
Aphrodite and Anvil were the World War II code names of United States Army Air Forces and United States Navy operations to use B-17 and PB4Y bombers as precision-guided munitions against bunkers such as those of Operation Crossbow....
drones. Torpex has long been superseded by H6
Composition H6
Composition H6 is a castable military explosive compound composed of the following percentages by weight:* 45% RDX* 30% TNT* 20% powdered aluminium* 5% paraffin wax as a phlegmatizing agent....
and PBX
Polymer-bonded explosive
A polymer-bonded explosive, also called PBX or plastic-bonded explosive, is an explosive material in which explosive powder is bound together in a matrix using small quantities of a synthetic polymer...
compositions. It is therefore regarded as obsolete, so Torpex is unlikely to be encountered except in the form of legacy munitions or unexploded ordnance
Unexploded ordnance
Unexploded ordnance are explosive weapons that did not explode when they were employed and still pose a risk of detonation, potentially many decades after they were used or discarded.While "UXO" is widely and informally used, munitions and explosives of...
.
Development
Torpex was developed at the Royal Gunpowder Factory, Waltham AbbeyWaltham Abbey Royal Gunpowder Mills
The Royal Gunpowder Mills, Waltham Abbey, an Anchor Point of the European Route of Industrial Heritage, , set in of parkland and containing 21 buildings of major historical importance, mixes history, science, and attractive surroundings...
, in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
as a more powerful military alternative to TNT. RDX
RDX
RDX, an initialism for Research Department Explosive, is an explosive nitroamine widely used in military and industrial applications. It was developed as an explosive which was more powerful than TNT, and it saw wide use in WWII. RDX is also known as cyclonite, hexogen , and T4...
was developed in 1899. Though very stable and serving as the reference point by which the sensitivity of other explosives are judged, it was too expensive for most military applications, and reserved for use in the most important products, such as torpedoes. Aluminium powder was also added to the mix to further enhance the effect. Although both RDX and TNT have a negative oxygen balance (RDX would require 9 oxygen atoms to oxidize all of its carbon and hydrogen but has only 6, while 2 molecules of TNT together would need 33 oxygen molecules but have only 12). However the aluminum powder is superheated by the explosion and combines with environmental oxygen in a highly exothermic reaction which generates additional heat and thus greater explosive product volume and expansive force. This produces a longer and more damaging explosive pulse than high explosive alone in a process similar to a thermobaric weapon. Beeswax
Beeswax
Beeswax is a natural wax produced in the bee hive of honey bees of the genus Apis. It is mainly esters of fatty acids and various long chain alcohols...
was also added to reduce sensitivity to shock and impact. Later, beeswax was replaced with a petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
-based product, and calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
was added as a moisture absorber to reduce the production of hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
gas under high humidity.
See also
- MinolMinol (explosive)Minol is a military explosive developed by the Admiralty early in the Second World War to augment supplies of Trinitrotoluene and RDX, which were then in short supply. The aluminium component in Minol significantly prolongs the explosive pulse, making it ideal for use in underwater naval weapons...
- Composition H6Composition H6Composition H6 is a castable military explosive compound composed of the following percentages by weight:* 45% RDX* 30% TNT* 20% powdered aluminium* 5% paraffin wax as a phlegmatizing agent....
- TritonalTritonalTritonal is a mixture of 80% TNT and 20% aluminium powder, used in several types of ordnance such as air-dropped bombs. The aluminium improves the total heat output and hence impulse of the TNT - the length of time during which the blast wave is positive...
- HexaniteHexaniteHexanite was a castable German military explosive developed early in the 20th century before the First World War for the Kaiserliche Marine, intended to augment supplies of trinitrotoluene , which were then in short supply. Hexanite is significantly more powerful than TNT on its own...
- Explosives used during WW IIExplosives used during WW IIAlmost all the common explosives listed here were mixtures of TNT, RDX or PETN. Please note that this is only a partial list; there were many others.NameCompositionAmatolAmmonium nitrate and TNTBaronalBarium nitrate, TNT and powdered aluminium...