RU2507186C2 - Detonator pellet - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to industrial blasting means, namely detonator pellet, intended for initiation of hole charges in drilling and blasting works at mining enterprises. Detonator pellet for industrial blasting consists of charge of explosive substance in plastic shell, provided with canal and one or two sockets and made from injection moulding mixture of trotyl with pentaerythritol tetranitrate (TEN). Mixture contains 45-55% of TEN with specific surface from 1100 to 2400 cm²/g or 56-100 wt % of powder-like pentolite, made on such TEN, of total charge weight. TEN is produced directly in technological process or is obtained by mixing product with specific surface larger than 2400 cm²/g and smaller than 1100 cm²/g, and powder-like pentolite contains from 45 to 55 wt % or from 88 to 92 wt % of TEN, trotyl constituting the remaining part.

EFFECT: invention ensures obtaining charge of higher quality as to homogeneity, more technological in manufacturing and more reliable in exploitation.

2 dwg

Description

The invention relates to the field of industrial blasting equipment. A check detonator from an injection mixture of trotyl with pentaerythritol tetranitrate (PETN) is claimed to be used to initiate borehole charges of industrial explosives during explosive drilling at mining enterprises.

Industrial blasting detonators (SH) from the TNT injection mixture with ten (pentolite) are widely used abroad, for example, the Swedish swords NDR-150, NDR-400, NDR-450 according to the technical data of the company Nitro-Nobel. AB. Domestic pentolite steels are also known, for example, the utility model according to certificate No. 12236 of June 3, 1999, the utility model according to the patent No. 36506 of November 10, 03, the invention according to the patent of the Russian Federation No. 2177927 of January 10, 02. All of them have a through channel and a socket for mounting it by means of initiation (detonating cord or non-electric initiation system - NSI) and are equipped with a cardboard or plastic shell. Some of the domestic SD have an additional socket for accommodating a duplicate NSI capsule in order to increase the reliability of operation, for example, RF patent for invention No. 2389969, RF patent for utility model No. 52165.

Checkers NDR-150, NDR-400 and NDR-450 can hardly be attributed to direct analogues of the claimed SD, since they are significantly different from domestic structurally. Their nest is actually a through step channel, and inside the charge between the channels there is a plastic vessel with bulk PETN. They are designed to use very weak means of initiation and such installation schemes (strapping) that are not used in Russia. The complexity of manufacturing such drafts is much higher than domestic.

The closest analogue (prototype) of the claimed SD to the authors was chosen to SD according to utility model No. 36506, which is a 50/50 pentolite charge (50% PETN) with a socket and a channel in a heat-shrinkable polyvinyl chloride shell. (It should be noted that, taking into account technological tolerances, pentolite is a composition in which the content of PETN can be from 45 to 55% by weight.).

The main disadvantage of the prototype, as well as other analogues, is due to the low sedimentation stability of pentolite, which complicates the manufacturing technology of SD and negatively affects their quality. The prepared pentolite requires continuous mixing until it is poured into the mold or case, and in the process of forming the black metal, the PETN is redistributed in height, as a result of which the lower part of the black metal charge is re-enriched with the ten, and the upper one is depleted in it. As a result, the difference in the content of PETN in the upper and lower parts of the charge can reach 10% or more. The likelihood of casting defects in the upper part of the charge also increases. This leads to the fact that different parts of the charge can vary significantly in density, monolithicity, power and susceptibility, especially for large-size metal drums. As a result, there is the possibility of failures of the operation of the stepper motor, as well as a decrease in the initiating effect on the column of a low-sensitivity industrial explosive borehole charge.

An object of the invention is the creation of a SD with a charge of a higher quality in terms of explosive uniformity, more technologically advanced in manufacture, and also more reliable in operation.

The technical result, according to the claimed solution, is achieved by using a specific dispersion (specific surface) or powdered pentolite made on such a ten taken in a predetermined ratio in the composition of explosives.

It is known that the sedimentation stability of a suspension is directly related to the dispersion of the filler (solid phase). The stability of the trotyl-ten system (50/50) could be increased by adding finely dispersed ten (with a specific surface of 4000-6000 cm ² / g) instead of the standard one (with a specific surface of 450-700 cm ² / g). However, such a ten can be obtained only by a special technology that makes the product very expensive, which cannot but affect the cost of ITD, and, therefore, its competitiveness.

The authors chose to study the ten with a specific surface area of 1100-2400 cm ² / g, which can be obtained in the usual process by adjusting the parameters of the crystallization mode and therefore practically does not differ from the standard ten in terms of cost. At the same time, as an option for increased industrial safety, the preparation of injection pentolite using a powdery pentolite product was also studied, in which the particles of ten were coated with TNT, and the ratio of ten / TNT could vary widely. The “cord” pentolite 90/10 (88-92% PETN) used for detonating cords, as well as the 50/50 pentolite, were chosen. Teng for powdered pentolite was used the same selected dispersion (1100-2400 cm ² / g).

In the preparation of injection molded pentolite 50/50 from powdered pentolite 90/10, 44% of TNT was added to 56% of powdered pentolite. When using 100% powdered pentolite 50/50, the product simply melted with stirring. It turned out that the molten pentolite is completely identical to the mixture made from individual components.

In injection pentolite, viscosity and sedimentation stability (delamination) were determined as two indicators characterizing the processability of the molten mixture.

The research results are presented in the graph of figure 1. Curve 1 shows the dependence of the tenon content deviation from the nominal value (ΔС,%) on its specific surface for 15 minutes of exposure, and curve 2 represents the dependence of the viscosity (ν, Пз) of the melt on the specific surface of the ten.

An analysis of the presented dependences shows that the viscosity of the pentolite over the entire range of selected values of the specific surface remains suitable for both manual (up to 40 poise) and mechanized casting (up to 25 poise).

At the same time, this specific surface area also provides sufficient sedimentation stability of the pentolite: the deviation of the PETN content from the nominal value in 15 minutes ranges from a few percent to tenths of a percent with a tolerance of ± 5%. The optimal range is from 1200 to 2300 cm ² / g, where both high sedimentation stability and low viscosity of the pentolite are ensured. However, studies in the conditions of a specific technology of forming drafts, when a significant part of explosives crystallizes in the first minutes of pouring, and after 5 minutes the mold is turned upside down and sedimentation changes direction, it has been shown that the explosive charge remains within tolerance when using a heater with a specific surface of 1100 cm ² / g.

It should be noted that the ten of a given range of dispersion (specific surface) can be obtained by mixing the product of the specific surface of less than 1100 cm ² / g with the product of the specific surface of more than 2400 cm ² / g Thus, the mixing of 60% tena of a specific surface area of 2455 cm ² / g and 40% of a tena specific surface area of 700 cm ² / g gives a product with a specific surface area of 1770 cm ² / g.

The design of the SD is shown in FIG. 2, where 1 is BB, 2 is the channel, 3 is the slot, 4 is the shell.

The design of a stepper motor with one socket and a channel is possible.

Claims (1)

A detonator bomb for industrial blasting, consisting of an explosive charge in a plastic shell, equipped with a channel and one or two nests and made of an injection mixture of TNT with pentaerythritol tetranitrate (PETN), characterized in that the mixture contains 45-55% PETN with a specific surface from 1100 to 2400 cm ² / g or 56-100 wt.% of powdered pentolita made on such PETN, of the total mass of the charge, the heating element is produced directly in the process or the product obtained by mixing a specific surface area Tew more 2400 cm ² / g and at 1100 cm ² / g, and pentols powder comprises from 45 to 55 wt%, or from 88 to 92 wt% of PETN, TNT -.. else.

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