Military explosives pressing

Definition of deton process) 79) Ya.B. Zel dovich. A.S. Kompaneets, "Teoriya Detonatsii , GosIzdatTekhrTeorLit, Moskva (1955) (Engl translation under the title "Theory of Detonation , published in I960 by Academic Press, NY) 80) Anon, "Military Explosives , TM9-1910 (1955), pp 37-40 (Deton theory)... 

Most military explosives are solid compounds which are manufactured in granular form, with bulk densities of less than 1 g cm-3. These granular compounds are then mixed with other explosive or inert additives to give explosive compositions with densities between 1.5 and 1.7 g cm 3. The explosive compositions are then cast, pressed or extruded into their final form. 

Jr, Properties of Explosives of Military Interest, PATR 1740, revised by O.E.Sheffield (April 1958XU)(Expls props of standard military explosives) 72)H.Taube A.G.Maddock, edits,"Chemistry of the Coordinate Compounds, Pergamon Press, NY,vl(1958X638 pp)... 

TNT is one of the important materials used for not only explosives for industry but also military explosives for blasting charges. Since metals are not corroded by TNT, it is cast directly into metal cases as well as pressed into warhead shells. In order to gain high explosive characteristics, TNT is mixed with other materials, such as AN, Tetryl, PETN, A1 powder, and nitramine partides121. The mixture of TNT and AN is named Amatol has a TNT/AN mass fraction ratio ranging from 0.5/0.5 to 0.2/0.8. The mixture of TNT and AN is melted and then cast. The mixture of TNT and A1 named Tritonal has a mass fraction ratio of TNT/A1 = 0.8/0.2. The mixture of TNT and HMX is named Octol composed of the mass fraction ratio of TNT/H MX ranging from 0.3/0.7 to 0.25/0.75. The maximum detonation velocity, 8600 m/s, is obtained when the density is 1800 kg/m3. 

TNT is one of the least sensitive of military explosives only ammonium picrate, nitroguanidine, and ammonium nitrate are less sensitive. Impact tests yield high values relative to other military explosives, but impact sensitivity increases sharply with increasing temperature, as shown in table 8-56. Diminishing sensitivity has been reported down to- 196°C. Gap and projectile test results indicate cast TNT is less sensitive than the pressed materiel. Test results from the mod-... 

Urbanski, T., Chemistry and Technology of Explosives, Vol. II, p. 181, Pergamon Press, New York, 1965. Military Explosives, Dept, of the Army Technical Manual TM 9-1300-214, p. 7-32, Washington, DC, 1967. Watson, S. C., and Winston, S. E., Proceedings of the Eleventh Conference on Explosives and Blasting Technique, p. 320, Society of Explosive Engineers, 1985. 

The requirements of the US Armed Forces are described in Military Specification MIL A-166C (6 January 1975) entitled, Ammonium Picrate (Explosive D) It covers one grade of material, representing two classes with respect to granulation. Class 1 material (coarse) is intended for use in the press-loading of shells, while Class 2 (fine) is used for the manuf of Picratol and other compns. The requirements are as follows ... 

Tetrazene is a light yellow crystalline substance, insoluble in water and most organic solvents. The density is low under normal conditions, but on pressing can reach approximately 1 g ml-1. Tetrazene is weak as an initiating explosive, and is therefore not used alone. It has no advantages to commend it for use in commercial detonators, but does find application in the manufacture of military and other percussion caps. Like diazodinitrophenol, tetrazene does not detonate when ignited in the open, but only when ignited under confinement. 

TATP is unique in that it is a material that never received any serious consideration for military or commercial applications. It was studied by numerous groups, but primarily for academic reasons. Minimal literature references exist on it. TATP was first reported by Wolfenstein in 1895 [6], Since that time, numerous recipes have been developed for its preparation. One of the most useful studies of its properties as an explosive was conducted by Rohrlich and Sauermilch [7], They determined that TATP had a TNT equivalency of approximately 88% based on lead block expansion. They prepared a firing train consisting of 0.05 g TATP (pressed at 250 kg/cm2) in contact with pentaerythrital tetranitrate (PETN) to produce reliable blasting caps. Other experiments determined that a 0.16-g portion of the peroxide (density = 1.35 g/cm3) could initiate TNT. 

When intended for use as a military propellant, the mass was either granulated or used in the form of fibers. When used as a mining explosive, it was a plastic pressed into boreholes... 

The two principal loading techniques are casting and pressing. All expls in common military use can be pressed, however, those that are castable are usually cast because of the greater convenience and flexibility of this process. As a rule of thumb, main bursting charges of large cal munitions are cast while small explosive components (initiators to boosters) are pressed... 

The pressure most frequently specified for charges used in military items is 10000 psi. Charges may be pressed directly into their containers or pressed.into molds and ejected as pellets. Where they are pressed into containers of lengths greater than the diameter, the explosive is usually loaded in increments... 

Primary high explosive, Extremely press ure/impact sensitive Secondary high explosive. Main charge in many military munitions... 

Explosives Sensitivity Data. Card-gap and projectile sensitivity, data are presented by Watson (Ref 1) for a wide variety of expl compns tested at the USBurMines laboratories in more or less standard test geometries. The results of both tests are in good agreement in that they provide the same sensitivity ordering fbr different subclasses of expls. Least sensitive were homogeneous liquids that did not exhibit a tendency, to undergo low-velocity detonation, AN-FO (Ammonium Nitrate-Fuel Oil), and most cast military expls. Of intermediate sensitivity were pressed and powdered military expls, cast Pentolite, permissible and nonpetmissible water-based expls, and one commercial two-component expl. The most sensitive were permissible and nonpermissible Dynamites and expls susceptible to low-velocity detonations Refs I) R.W. Watson, 1 Card-Gap and Projectile Impact Sensitivity Measurements, A Compilation , USBurMines Information Circular 1C 8605(1973)... 

TM 9-1300-214/TO 11 A-l-34(1967) [Superseding TM 9-1910(1955)], pp7-83 and 7-84 (Dynamites, civil and military) 67) T. Urbanski, "Chemistry and Technology of Explosives , (Translated from Polish by Marian Jurecki), pergamon Press, NY.,. 407 / Mir.inv Fxe c ives with 98 refs) 398-527 (The Manufacture of Mining Explosives, with 14 refs) Note This excellent description was obtd after our write-up on Dynamites was completed) 68) Encyclopedia Britan-nica 8(1967), 974-76 69) E.I. DuPont de... 

Note Most TNT blocks arc made of pressed explosive, which can be reliably detonated by a commercial number 8 blasting cap. Cast TNT has a much higher density than the pressed block and is therefore more powerful but also harder to detonate. Cast TNT requires the equivalent of a military J-2 blasting cap or a booster. Cast Pentolite is sensitive to a number 8 blasting cap. 

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