INFLUENCE OF THE TYPE OF DONOR CHARGES ON THE DETONATION RATE OF LOW-SENSITIVITY EXPLOSIVES

The article discusses the creation, testing and implementation of new donor charges designed to initiate low-sensitivity explosives. The cast booster donor charges are made entirely of explosives obtained from the disposal of unnecessary ammunition – TNT, RDX and TEN. The donor charges differ from the mass-produced ones, and have a mass of 150 to 900 g. They also have high explosive characteristics: velocity of detonation from 7200 to 7500 m/s, density of 1.6 g/cm3, excellent water resistance and strength. Their initiating ability on low-sensitivity explosives is significantly better than the one of TNT presses. The velocity of detonation of the main charge of a low-sensitivity emulsion explosive initiated with a cast booster is up to 700 m/s higher than when initiated with a TNT presses. It is especially important when building objects in the constrained conditions, at development of mountain territories for decrease in action of shock air waves and elimination of possibility of mountain collapses and landslides In article advantage of use of cast intermediate detonators on safety of explosive works is proved at development of mountain territories. The new design allows an increase in the security of initiating the charges in the boreholes, which allows them to be initiated with two detonators simultaneously.

Control of density and velocity of emulsion explosives detonation for ore breaking

Purpose.Development of a new procedure for calculating the density of emulsion explosives (EE), that will allow determining the detonation velocity along the charging length, depending on the inclination of boreholes during ore breaking. Methodology.A calculation method for the redistribution of EE density and mass in boreholes at different angles of inclination has been developed by using the well-known laws of hydrostatics. Measurement of the detonation velocity of the EE Ukrainit-PP-2B was conducted by using the method of polygon experimental tests. The numerical simulation of changes in the detonation velocity of explosives in boreholes was conducted by using the proposed method and established regularities. Findings.Methods of calculation of EE density changing along the charging column length under the action of hydrostatic pressure at different angles of inclination of both ascending and descending boreholes have been developed. Based on experimental data, regularities of detonation rate changing from density and charge diameter for EE Ukrainit-PP-2B, varying according to exponential law have been established. The rational initial density of EE Ukrainit-PP-2B has been established for ores breaking by boreholes, which is equal to 8001000 kg/m3, at which the detonation rate along the length of the charge column at different angles of inclination of the boreholes is maintained. The obtained results will allow controlling density and detonation velocity during ore breaking. Originality.The density of EE increases in the formed charging column under the action of hydrostatic pressure: in ascending boreholes from the face, while in descending boreholes from the brow. Practical value.Application of the calculation results of EE density at different inclination angles of boreholes makes it possible to determine in the charge column sections with its critical values more than 1410 kg/m3, at which a sharp attenuation of the detonation rate begins. Consideration of this phenomenon makes it possible to prevent the occurrence of failures at the explosion of charges in boreholes during ore breaking.

DIRECTIVITY EFFECT OF ELONGATED CHARGES

After years of development it has been determined that the energy from the detonation of a low velocity explosive in an elongated column approaches a unidirectional pattern. This column is placed in the subweathering material extending [Formula: see text] to 2 wavelengths in lengths depending on the frequency of energy desired. A study of the theory of propagation showed that greater directivity can be obtained from the same length of charge by using a powder with a detonation rate less than the side wall velocity of the shot hole. As the detonation rate of the column is lowered relative to the side wall the directivity increases and the downward energy decreases. The optimum balance of these factors is a detonation rate about [Formula: see text] of the side wall velocity. Experiments on elongated charges indicate that a very important effect of directivity is the elimination of “ghosts” as well as the reduction of horizontal energy. Interpretation may be greatly facilitated by a reduction in unwanted energy. Character is no longer dependent upon hole depth. Records have a more uniform appearance. Elongated charges produce many of the same effects as shallow pattern holes, but under many circumstances they are easier or less expensive to use.

CATALYZED NITRATION OF AMINES: I. DINITROXYDIETHYLNITRAMINE

It has been found possible to convert diethanolamine to β,β-dinitroxydiethylnitramine by inclusion of hydrogen chloride or one of its salts as catalyst. The structure of this powerful explosive has been demonstrated by an alternative synthesis involving nitrosation of dinitroxydiethylammonium nitrate, followed by subsequent oxidation of dinitroxydiethylnitrosamine to the corresponding nitramine. The nitrosamine, which is unstable in boiling water, is evidently an impurity in the crude nitramine. It may be removed from the stable nitramine by blowing the suspension of molten crude product with steam. The pure explosive is a stable low-melting solid with power and detonation rate higher than those of nitroglycerin. Its insensitiveness to impact as compared with nitroglycerin recommends it as a replacement for the latter substance in explosive compositions.