Diameter of explosive

I. Jaffe "A Method for the Determination of the Critical Diameters of Explosives , NavWepsRept 7360(1960), USNavalOrdnLab, White Oak, Silver Spring, Md... 

In this detonator, the diameter of explosive column is in gradually increasing steps, because the charge diameters are so much... 

The problem that remains is the study of the interaction of a shock with a matrix of holes in three-dimensional geometry. The basic two-dimensional processes involved in the failure of detonation, the failure diameter of explosives, and the sputtering initiation observed for density discontinuities near the critical size have been described. The three-dimensional study of the interaction of numerous failures and reignited detonations which is necessary for a complete numerical description of these problems must await new computing hardware ... 

Limiting (or Critical) Charge Density-Diameter of Explosive Charges. See Detonation Velocity-Charge Diameter and Density Relationship in Encycl 4 (1969), D641-L to D656-L... 

Velocity of detonation dependent on diameter of explosive charge, i.e. critical diameter Does not usually revert to deflagration, if propagation of detonation wave fails explosive composition remains chemically unchanged... 

The failure diameter of explosives has been found to decrease with increasing temperatures and since the failure diameter is directly related to the Pop Plot, the explosives are more shock-sensitive with increasing temperature. 

Ra.m Tensile. A ram tensile test has been developed to evaluate the bond-2one tensile strength of explosion-bonded composites. The specimen is designed to subject the bonded interface to a pure tensile load. The cross-section area of the specimen is the area of the aimulus between the outer and inner diameters of the specimen. The specimen typically has a very short tensile gauge length and is constmcted so as to cause failure at the bonded interface. The ultimate tensile strength and relative ductihty of the explosion-bonded interface can be obtained by this technique. 

Volume of vessel (free volume V) Shape of vessel (area and aspect ratio) Type of dust cloud distribution (ISO method/pneumatic-loading method) Dust explosihility characteristics Maximum explosion overpressure P ax Maximum explosion constant K ax Minimum ignition temperature MIT Type of explosion suppressant and its suppression efficiency Type of HRD suppressors number and free volume of HRD suppressors and the outlet diameter and valve opening time Suppressant charge and propelling agent pressure Fittings elbow and/or stub pipe and type of nozzle Type of explosion detector(s) dynamic or threshold pressure, UV or IR radiation, effective system activation overpressure Hardware deployment location of HRD suppressor(s) on vessel... 

Figure 7.2 Diameter of fireball versus quantity of explosive...

The sample eapsule is plaeed in a tight-fitting 4340 steel fixture that serves to support the eopper eapsule. Pressure from the detonation of the explosive is transmitted to the eopper eapsule through a mild steel driver plate. This plate is also lapped optically flat on both surfaces. The mild steel acts to shape the pressure pulse due to the 13 GPa structural phase transition. With proper choice of the diameter of the driver plate and beveled interior opening of the steel fixture, shock deformation of the driver plate acts to seal the capsule within the fixture. 

The high explosives, baratol or Composition B-3, are used to produce the plane wave loading into the driver plates. These explosives have been widely studied in substantial work at Los Alamos. Plane waves are introduced into the explosive pads with either P-22 or P-40 plane-wave generators developed at Los Alamos. The Bear system is based on the 56 mm diameter of the P-22, while the larger sample size Bertha system is based on the 102 mmdiam of the P-40. More details on sample dimensions are reported by Graham [87G03]. 

Figure 4.19. Diameters of side-on overpressure circles for various explosive yields (1 ton 2000 lb) (based on free-air bursts).

To avoid explosion, the compounds can be decomposed via hydrolysis in liquid solution. Ultra-fine particles are obtained in water and water-ammonia media. Hydrolysis in HC1 and HN03 solutions leads to the precipitation of an agglomerated powder of both tantalum and niobium oxides. Agglomerates obtained are up to 12 pm in diameter, while the estimated diameter of the smallest ciystalline particles varies in the range of 0.01-0.5 pm [512]. 

An example of the separation of a mixture of explosives on a C8 column is shown in figure 7. The column was 3.3 cm long, 4.6 mm in diameter and packed with 3 pm C8 silica based reverse phase. This short column has a potential efficiency of 5,500 theoretical plates. 

A detonator, in the form of explosive plates made with tetryl then a screen made of cellulose acetate plates is placed in a wooden container. A 26 mm diameter cylinder full of the substance to be analysed is placed on the screen, and finally a steel plate on top of the cylinder is added. If the substance transmits the detonation, the steel plate will be pierced and not projected. Piercing serves as an indicator of detonation transmission. The number of cellulose acetate disks needed between the sample and the detonator to prevent the detonation from being transmitted is found. Only one is needed for most chemical substances, but with m-dinitrobenzene, 240 are required. 

Figure 14.10 illustrates the method of seismic prospecting on land by what is known as reflection shooting. A hole usually 10 to 12 cm in diameter is drilled to a depth of 15 to 30 m. The charge of explosive is likely to be 5 to 12-5 kg and the stemming used is usually water. As the explosive must fire under a depth of water which may exceed 45 m, special varieties of gelatines are employed (see p. 53). Alternatively, a powder explosive can be sealed into pressure-resistant metal containers. Special detonators are also employed, not only to withstand the possible head of water, but also to have a specially short bursting time (see p. 113). 

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