Explosives Flashcards
is a solid or liquid substance (or a mixture of substances) that is in itself capable by chemical reaction of producing gas at such a temperature and pressure and at such a speed as to cause damage to the surroundings.
Explosive substance
the year of discovery of nitroglycerin and nitrocellulose and after which dynamites and Mercury formulate dusting cap were invented.
1850
Year smokeless powder was made
1867
is a material that, under the influence of thermal or mechanical shock, decomposes rapidly and spontaneously with the evolution of a great deal of heat and much gas.
Explosive
Classification of explosives
1) Initiating or primary explosives (detonators)
2) High explosives-trinitro-toluene (T.N.T)
3) Low explosives or propellants-colloided cellulose nitrate (smokeless powder)
sensitive materials which can be made to explode by the application of fire or by means of a slight blow.
- used in primers, detonators, and percussion caps
Initiating or primary explosives (detonators)
Examples of initiating or primary explosives (detonators)
lead azide, mercury fulminate, diazodinitro-phenol, lead styphnate (lead trillitro-resorcillate).
insensitive to both mechanical shock and flame but explode with great violence when set off by an explosive shock such as that which would be obtained by detonating a small amount of an initiating explosive in contact with the high explosive.
High explosives
Examples of high explosives
trinitro-toluene (T.N.T.) - amatols, pentaerythritoltetranitrate, cyclonite (hexogen or R.D.X.), tetryl, dynamites, nitro-starch.
is used as a booster between the initiating and high explosive
Tetryl
refers to all black powder having sodium or potassium nitrate as a constituent
Black blasting powder
evolve large volumes of gas on combustion in a definite and controllable manner.
Low explosives
- mode of decomposition is burn.
- less shattering
Low explosives or propellants
One which has been approved by the US Bureau of Miners or British Ministry of Fuel and Power for use in gas or dust-filled mines.
Permissible explosive
constitutes over 65 percent of the weight of the permissible
ammonium nitrate explosives
Permissible explosive includes:
▪ ammonium nitrate explosives -
▪ hydrated explosives
▪ organic nitrate explosives
▪ nitro-glycerine explosives - contain an excess of free water or carbon
Property of an explosive that may be measured by exploding a small quantity of it in a sand bomb
Power or Brisance
a heavy-walled vessel designed to resist the explosion without being ruptured
Sand bomb
It contains 200 grams of Ottawa silica sand, all of which passes through a 20-mesh sieve and all of which is retained on a 30-mesh sieve.
Sand bomb
measures the power of the explosive by measuring the ballooning of a soft lead cylinder in which the explosive is inserted and exploded.
Trauzl block test
How deep is the center hole of the Trauzl block?
125 mm
This property of an explosive is determined by finding the height from which standard weight must be allowed to fall in order to detonate the explosive.
sensitivity to impact
Recently, methods have been developed for determining the velocity of detonation by means of
high-speed photography
is dependent on many factors including the composition of the explosive, the density at which it was loaded before firing, and the degree of confinement.
velocity of detonation
Certain accelerated aging tests are frequently run to determine the
stability of explosives on storage
contains a small amount of a primary explosive or sensitive mixture
Primer
Projectiles designed for _______ must have heavy walls and contain an explosive so insensitive to impact .
armor piercing
▪ extremely low sensitivity to impact
▪ low cost of production
▪ excellent thermal stability
Guanidine picrates
At high enough temperatures, ________ can violently decompose on its own. This process creates gases including nitrogen oxides and water vapor.
ammonium nitrate
Special projectiles loaded with lead balls embedded in a matrix of rosin or bakelite and equipped with a time fuze causing them to explode in mid-air are known as
shrapnel
pushed black powder out of use as a military propellant.
Nitrocellulose
The cellulose molecule is a highly complicated one with a molecular weight that is frequently as high as
300,000
The finished nitro-cellulose should not be allowed to become acid in use or storage because
this catalyzes its further decomposition.
added which reacts with any trace of nitrous, nitric, or sulfuric acid that may be released due to the decomposition of the nitro-cellulose and thus stop further decomposition.
Stabilizer
Stabilizer for smokeless powder
diphenylamine (diphenylurea in Great Britain)
Stabilizer for celluloid
Urea
The nitro-cellulose produced in this manner contains about 12.6% nitrogen and is known as
Pyrocotton
Cotton nitrated to contain 13.2% nitrogen or greater is known as
Guncotton