Detonation rate tetryl

Note PA primers were used in each test. A specially constructed device was used for measuring vels of molten samples, such as at temps of 173 183°all the above expls, except PA. Extremely high vel for TNN at 183° was due to decompn of chge prior to initiation McGarry Stevens (Ref 2) detd by drum camera method the rates of deton of Tetryl, RDX Comp A-3 (all in pelleted form) 50/50 Pentolite, TNT Comp B (all cast) and hand-tamped Comp C-4. The rates of these sticks 1-1/8 inch in diam by 18 inches long were measured after exposure to initial low, ambient and high temps. It was found that the deton rates of these expls,... 

The rate of detonation of tetryl is reported by various authors as follows ... 

Abel Powder or Picric Powder. A mixt for priming PA(picric acid) invented in 1869 by Sir F. A. Abel Amm pi crate 40 K nitrate 60% (Ref 1). French used a similar compn called Brugere(poudre). In Ref 2, the compn of picric powder is given as Amm picrate 43 A K nitrate 57% vel solid.dec without melting brisance — less than TNT ballistic strength ca 75% TNT deton rate ca 3500 m/s vs 6900 for TNT sensitivity to impact, rifle bullet and initiation — comparable to tetryl stability and compatibility with metals — comp arable to Amm picrate. Was used during WWII by the British as a booster in AP projectiles filled with Sbellite(qv)... 

Detonation Rate. According to Fliirscheim (Ref 16, p 104T), the velocity of deton is "great" and exceeds that of tetryl and NG,... 

Properties Fine granular powder, white or of a lights buff color. M. P. 141°, Quite sensitive to blows, is more readily detonated than tetryl. Detonation rate (d = 1.63) 8000-8300 m/sec. One of the most powerful modern high explosives.30... 

Properties Brownish crystals. Melts with decomposition at 210° and deflagrates at about 226 . Powerful and sensitive high explosive, similar to Tetryl. Detonation rate (d = 1.6) 7500 m/sec. On long storage stability not very satisfactory, particularly in presence of moisture, which tends to promote hydrolysis.37... 

J.J. Minnick G.W. Beil, USP 3394038 (1968) CA 69, 53326(1968) [High-density AN-FO expl compns contained a dense AN (d = 1,3—1.7), ground to 8 to 200 mesh and mixed immediately and thoroughly with fuel oil, A typical compn consisted of ground AN 60.2, whole prilled AN 30.0, No 2 fuel oil 2.5, powd coal 4.0, Ca chloride 2.0 and clay 1.3%. This compn had package d 1.11 and exhibited deton rate of 10500ft/sec when primed with Tetryl]... 

When a 0.5 gram sample of tetryl is heated at a rate of 20°C per minute, ignition occurs between 190°C and 194°C. If the temperature of a sample is held at 180°C ignition occurs in 40 seconds. The minimum primary charges necessary for reliable detonation of tetryl with mercury fulminate is 0.20 to 0.29 grams and with lead azide is 0.025 to 0.10 grams. Tetryl containing 60 percent water cannot be detonated by a commercial detonator. Shock sensitivity as measured by the gap tests are summarized in table 8-30. 

Both the Pb disc test and the steel dent test are of particular significance to stab detonators. As a matter of illustration, the steel dent test (Ref 10) consists of firing a detonator in direct end-on contact with a steel block. The depth of the dent produced is a measure of output. The depth, or better, the volume of the dent correlates well with initiation effectiveness. The low-rate detonation, which crushes nearly as much sand as high-order detonation, makes no dent in a steel plate. It has been demonstrated that the depth of the dent is proportionate to the excess of pressure over the yield strength of the steel of the dent block, integrated over the volume of the detonation head. It has been found that a detonator of 0.190-inch diameter or larger, which produces a dent 0.010 of an inch deep in a mild steel block, will initiate a lead of Tetryl or RDX under favorable conditions. Specification requirements for detonators to be used in fuses are usually at least 0.015 to 0.020 inch in depth, and many produce dents up to 0.060 inch deep... 

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 ... 

TFEt Tetryl 2,4,6-Trinitrophenyl-/S,j8,j8 trifluoroethylnitramine are reported by Avrami et al (Ref 2). Their behavior at different exposure levels is compared with the behavior of the parent compds, TNB TNT RDX HMX are also included as controls. The determinations made on each expl were wt loss, vacuum, stability, mp, IR spectra, DTA, TGA, impact sensitivity, expln temp, and rate of detonation as a function of total gamma exposure. A brief description of the expln-containment irradiation capsule designed used in these studies is also given... 

According to Domanski and Mieszkis [73] the rate of detonation, at a density of loading of 0.93 in a paper tube 10 mm dia., is 5200 m/sec (under the same conditions the rate of detonation of penthrite was approximately 6000 m/sec). Cook [58] found the rate of detonation to be 5530 m/sec at a density of loading of 1.0. The substance is similar to tetryl in sensitiveness to impact. Its chemical stability is slightly less than that of tetryl. Its ignition temperature ranges from 165 to 170°C. 

E. Jones and Mitchell [52] found that under the influence of a standard No. 6 detonator, a charge of tetryl at a loading density of 0.94 and 25 mm dia. initially detonates at a low rate which increases after a certain distance (the authors give no figures). 

As an explosive the substance is very powerful. Its expansion in the lead block is about 500 cm3, j.e. its explosive strength is midway between that of tetryl and penthrite. At a density of 1.54 it detonates at a rate of 7500 m/sec. 

In the United States a mixture of 60% cyclonite and 40% TNT was used under the name of Cyclitol as a filling for aerial bombs. The density of the cast explosive was 1.65-1.70, its rate of detonation 7800 m/sec, and in the ballistic pendulum it gave a value of 130 (100 for TNT). In the United States this mixture is considered to be only a little more sensitive to impact than TNT with a stability similar to that of cyclonite. This does not agree with T. Urbanski s [5] investigations according to which the sensitiveness to impact of such a mixture, in a powdered form, and its ignition temperature (225°C) approximate to the corresponding values for tetryl. 

The explosive properties of mixtures with ammonium nitrate depend on the quantitative relationship between the oxidizing agent and the explosive or combustible substance. According to Parisot and Laffitte s [9, 47] investigations the explosive properties of mixtures of aromatic nitro compounds with ammonium nitrate vary with the change in composition of the system in an almost rectilinear manner. The graph in Fig. 69 shows how the rate of detonation depends on the composition of mixtures of tetryl or picric acid with ammonium nitrate. T. Urbanski et al. [48] also obtained a rectilinear relationship for nitrostarch mixtures with ammonium or sodium nitrate (Fig. 71, p. 265). 

Fig. 69. The relation between the rate of detonation and the composition of tetryl or picric acid mixtures with ammonium nitrate (Parisot and Laffitte [9]).

According to Kast [28] nitrocellulose powder does not detonate even when very strongly initiated (e.g. 50 g of picric acid or 100 g of tetryl), but may explode with a rate from 1000 to 1800 m/sec. 

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