Shattering effect

Pentaerythritol tetranitrate (PETN) is a colorless crystalline solid that is very sensitive to initiation by a primary explosive. It is a powerful secondary explosive that has a great shattering effect. It is used in commercial blasting caps, detonation cords, and boosters. PETN is not used in its pure form because it is too sensitive to friction and impact. It is usually mixed with plasticized nitrocellulose or with synthetic rubbers to form PBXs. The most common form of explosive composition containing PETN is Pentolite, a mixture of 20 to 50% PETN and TNT. PETN can be incorporated into gelatinous industrial explosives. The military has in most cases replaced PETN with RDX because RDX is more thermally stable and has a longer shelf life. PETN is insoluble in water, sparingly soluble in alcohol, ether, and benzene, and soluble in acetone and methyl acetate. 

Brisance or Shattering Effect Tests. See Vol 1, pp VIII-IX and Vol 2, pp B299-B300... 

Detonation (and Explosion), Mechanical Effects of. These include blast effects, which are described in Vol 2 of Encycl, pp B180 ff and shattering effect, described in Vol 2, pp B265 ff, under BRISANCE. The latter effect causes fragmentation of bombs, shells, grenades, rockets, mines, torpedoes,etc... 

But when the shock effect is impinged on other matter, it is indicated by its shattering effect (brisance) - not by the total work effect of the explosive. This might be proved by making Sand Tests of Tetryl loaded at different densities. With different densities and consequent different rates of detonation, there should be different amounts of sand crushed ... 

Detonation velocities power values of various expis are given in Table 1, Vol 2 of Encycl, p B266ff under Brisance or Shattering Effect... 

It is to be Qoted that the total effective work capacity of an explosive usually has two resultants — (1) fragmentation and (2) blast effect or the movement of matter. These can be measured separately. As there is no shattering effect in the ballistic pendulum test, this test may be considered to measure total effective work capacity Ref W.H. Rinkenbach, Private communication, Allentown, Pa, Feb 20, 1964 Detonation, ZND (ZeTdavicb- von Neumann-Doering) Model. See Detonation NDZ (Neumann-Doring-Zel dovich) Theory, pD454... 

Kast Brisance Meter. See Brisance in Vol 1, p IX Compression Tests in Vol 1, p X also see under Brisance or Shattering Effect in Vol 2, pp B265-L to B297-L, and Brisance Test Methods in Vol 2, pp B299-L to B300-R... 

Vol 2(1962), pp B105 B106 (Berthelot s Characteristic Product) and p B265-R, under BRISANCE OR SHATTERING EFFECT... 

Foamed Explosives for Floating Mine. An invention fcy Stark (Ref 1) provides a floating mine which consists of an expl having a closed-cell foam structure of greater and more shattering effect than die same wt of high density expl. Buoyancies of these expls are of 20 to 50 lbs per cu ft. The foamed expls consists of HE s (such as TNT, NC, PETN or RDX) bonded by a thennosetting resin Ref H,J. Stark, USP 2845025(1958) Ordo 43, 662(Jan-Feb 1959)... 

It must be noted that for closely confined explns, the force (f), the rate of deton (D) and density (d) are all of great importance. In order to obtain a means for rating confined expls, all these factors must be taken into consideration. This was done by Kast, who proposed calling the product of these values brisance or shattering effect and designated it as B (See the beginning of this Item and in Vol 2 of Encycl, p B265 R) The comparative brisance by Kast,... 

O 25.99% crysts, mp 81—82° was obtd when o-m ethoxy benzoyl chloride was slowly added over 30 mins to a soln of Na peroxide in w contg a few drops of Triton 720 (Rohm 8c Haas Co trademarked surfactant) A lg sample heated 4.5°/min decompd suddenly with a shattering effect a loud report a lOg sample at 75° exploded after 30 mins. At 30° the compd liberated 98.2%... 

Distler, Blecher Lopex Explosives were patented safety expls consisting of nitro-xylenes as chief constituents. The nitro compds had varying amts of cumol, mesitylene xylene nitro constituents mixed with AN, other nitrates or KClOg or metal oxides. For example, if 12 parts nitrated solvent naphtha are intimately mixed with 88 parts of AN, a very insensitive expl is produced, which is unaffected by either shock or percussion which does not explode at 200° or in an open flame, but which has an extremely powerful shattering effect when suitably detonated Ref Colver (1918), p259... 

Commercials Solvents Corp, FrP 1550911 (1968) CA 71, 93220a(1969) [Expl slurries comprising AN, methanol, water, urea nitrate, guar gum or a resin UCAR C-149 or WSR-131 are described. For example, a mixt of AN 67.4, methanol 20.0, water 2.0, urea nitrate 10.0 WSR-301 resin 0.6 parts was prepd and poured into borehole (200mm diam) in rock. With 0.5kg Pentolite primer per 2.4m long borehole, complete deton and an excellent shattering effect on rock were obrd]... 

Effet brisant (jFr). Shattering Effect or Brisance. See Vol 2, pp B265 ff... 

A detailed discussion of Kast s calcn is given in Vol 2 of Encycl, p B265, ynder BRISANCE OR SHATTERING EFFECT. Kast s formula (which he himself called, accdg to Naoum, p 153, approximate) permitted the determination of specific energy f, if B, d and V were known. Brisance (B) can be detd experimentally by Kast s or Hess Crusher Tests, described under "Compression (or Crusher) Tests for Determination of Brisance , in Vol 3, pp C492 C493 or by Quinan Method... 

Nitroglycerine is a very powerful secondary explosive with a high brisance, i.e. shattering effect, and it is one of the most important and frequently-used components for gelatinous commercial explosives. Nitroglycerine also provides a source of high energy in propellant compositions, and in combination with nitrocellulose and stabilizers it is the principal component of explosive powders and solid rocket propellants. 

NG + antifreeze additives) is replaced by AN and the remaining nitric ester acts as a sensitizer for the insensitive AN. These expls, which originated in the USA about 30 years ago, are notable for their heaving rather than shattering effect and their strength is... 

Brlsanca or Shattering Effect(Brieance, in Fx) (Brisanz, in Gee) (Poder tompedor or Brisancia, in Span) (Potcxe dirompente, in Ital) can be approximately measured by the following methods a)Comprossion Tests... 

Hess Brisance Test. See under Brisance (Shattering Effect) in Vol II... 

B (value) see Brisance or shattering effect 2 B265-B300... 

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