RU2596212C1 - Method of formation of explosive charge - Google Patents

Abstract

FIELD: blasting operations.

SUBSTANCE: invention relates to production of explosives (E) and can be used for charge of shot holes, blast holes, regardless of their water cut, at open mining works and on special blasting operations, as well as during construction. Method of formation of explosive charge is in production of combined charge of two types of explosives, which are located concentrically to each other. For this purpose, a pipe is installed in the charged course, then the space around it is filled with explosive, the stem is made or not, after which the pipe is filled. At that the explosive, placed in the central part of the charge has detonation speed that exceeds detonation speed of the explosive, located in the peripheral part (outside of the pipe).

EFFECT: concentric charge design provides to increase efficiency of explosion, to reduce environmental load on environment, to simplify and improve safety of loading operations.

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Description

The invention relates to the field of production of explosives (BB) and can be used to charge blast holes, holes, regardless of the degree of water cut, in open cast mining and in special blasting operations. It may also be useful for construction.

A known method of loading and charge design, including a combined charge of two types of explosives, which are located in direct contact concentrically to each other, the central part of the charge with an axial through cylindrical channel is represented by an explosive whose detonation velocity is greater than the detonation velocity of the explosive located in the peripheral part, In this case, the oxygen balance of the explosive in the central part is lower than the oxygen balance of the explosive located in the peripheral part of the charge, in which there may be a pure oxidizing agent (ammonia a) without fuel [1].

The disadvantage of this method is the use in the charge design of unbalanced and / or unmixed explosives or explosives and ammonium nitrate, which as a result of the explosion will lead to a low energy output and a large yield of toxic explosion products, which is confirmed by the data obtained in [2] - "Experimental explosions showed that with poor-quality mixing up to 40% of the explosion energy is lost." Moreover, the air channel located in the central part of the charge, not filled with energetic material, reduces the total charge energy, in comparison with filling the charge cavity (well) of the explosive completely.

A known method of loading dry and weakly watered wells, according to which the components of the combined charge, including emulsion and granular explosives, are fed into the well separately, without mixing, to form an external glass of granular explosives and an emulsion explosive placed inside the specified glass during charging [3 ].

The disadvantage of this method is the limited scope of its application, namely only dry and slightly watered wells. In addition, the diameter of the wells should be large enough, because granular and emulsion explosives have a large critical diameter of detonation, which creates certain difficulties in the application of this method in wells of small diameter and holes. In addition to this, the water released during the gradual destruction of the emulsion, which is usually observed in practice, will begin to destroy the granular explosive. This is mainly due to the dissolution of ammonium nitrate and the deposition of solid fuel in the lower part of the charge column, and light, mainly liquid, fuel in the upper one.

A known method of forming a borehole explosive device in a well, including an intermediate detonator, is placed in the shell in the form of a pipe [4]. Here, as an example, a description is given of the practical implementation of this method, where wells with a diameter of 250 mm were charged on a ledge 15 meters high. Serial hose charges SHZ-4 with a diameter of 80 mm, 10 m long, and a charge mass of 3.9 kg were used as an intermediate detonator on 1 m of length. The annular cavity in flooded wells was filled with thickened hot solution of ammonium nitrate, and in dry wells with granular nitrate with the introduction of 6% diesel in the first and second cases. It should be noted that the ShZ-4 hose charges shown in the example have a flexible elastic shell (kapron) [5], therefore it is not entirely clear, and the shell mentioned here is in the form of a pipe, i.e. an example, in our opinion, does not correspond to the proposed claims.

The disadvantage of this method is the need for preliminary placement in the well of a rather sensitive explosive, which is usually used in the construction of intermediate detonators, and hose charges are no exception [5]. At the same time, the possibility of any external negative effects on the intermediate detonator during further charging of the well, which can lead to both destruction of the shell of the charge and explosive, which is associated not only with a decrease in the efficiency of the charge, but also with the safety of preparatory work, is not ruled out. In addition, the handling of finished charges is associated with a large number of hazardous operations that are carried out mainly by hand: loading, unloading, carrying, lowering and securing (positioning) the weight of heavy charges in the desired, centrally symmetrical position inside the well. Moreover, a large mass fraction of the intermediate detonator in the charge structure, the explosive of which has a large negative oxygen balance, will lead to the formation of an excess of toxic explosion products.

The objective of the invention in relation to the method of loading wells, holes is to simplify and increase the safety of the loading operation when creating a concentric charge design, which allows to increase the efficiency of the explosion, as well as reduce the environmental load on the environment.

1. The technical result is achieved by the fact that in the method of forming an explosive charge, comprising a combined charge of two types of explosives, which are arranged concentrically to each other, the central part of the charge being an explosive whose detonation velocity is greater than the detonation velocity of the explosive located in the peripheral part, first in the chargeable working hole is installed in the pipe, then the space around it is filled with explosives, jamming is done or not, after which a liquid explosive (LHM) is placed in the pipe, for example, based on diazot t traoksida.

Used liquid-based substances based on the diazot tetraoxide should have zero oxygen balance or close to it (deviation of not more than 10% from zero). As explosives located outside the pipe, any other industrial explosives (bulk and pouring) can be used. The speed of their detonation is usually significantly lower than the speed of detonation of explosives and, in particular, explosives based on the diazot tetraoxide. Explosives are selected depending on the task, in the first place is their power and water resistance.

Experience has shown that a means of increasing the efficiency of the explosion of a borehole explosive charge generated on the basis of a mixed explosive is linear (axial) initiation, which is realized by preliminary placing a linear charge of an explosive along the borehole axis with a higher detonation velocity. “A linear initiator eliminates the attenuation or disruption of explosive detonation along the length of the charge due to any defects in the charge structure” and, when used, “an increase in the size of the rock crushing zone is observed” [2].

2. The pipe used must be made of a material that is chemically resistant and compatible with the explosives and liquid explosives used, and it is desirable (recommended) to use a material that, taking part in the explosive transformation, increases the efficiency (energy) of the explosive process. For this, pipes made of aluminum or of its alloys with magnesium, magnesium and silicon, manganese can be used. Pipes of metal-plastic or filled plastic, including aluminum, magnesium or other energetic materials, which can take part in the explosive transformation reaction, can also be used.

Pipes should be thin-walled (from economy), but durable. The wall thickness is determined by the specific application conditions and depends on the depth (length) of the charged mine. If necessary, pipes can be assembled, screwed from individual links (segments of short length), however, at the same time, the tightness of the bottom part (plug) and the joints of the pipe sections must be ensured, for which, for example, coupling-type devices can be used.

3. If it is technologically difficult or expensive to make a pipe entirely from the required material, then only the external and / or internal coating of the pipe with materials that can take part in the explosive transformation with a positive effect can be done. For coatings, you can use compositions based on aluminum or its alloys, as well as its mixtures with other substances. Modern technology allows you to apply such coatings both outside and inside the pipe. If necessary, in the field, you can manually glue the outer surface of the pipe with aluminum foil.

However, in any case, it is necessary to remember that all the materials used must be chemically compatible with each other, therefore, the coating of the pipe may be necessary for the case of creating a protective layer between the pipe material and the explosive or explosive substances.

4. Life-giving devices can be made of non-explosive components directly in the pipe, the bottom, end part of which must be welded or sealed, etc. This condition applies to all cases of using the pipe under life-giving devices mentioned in the description. The manufacturing technology of explosives from non-explosive components, which can be taken as a basis, is described in RF patent No. 2416781 [6].

5. From an environmental point of view, as well as based on the conditions for fulfilling safety requirements, it is desirable (recommended) that the pipe used in the upper part has special devices, for example, in the form of tubes, as for pouring liquid explosives, based on diazotetraoxide, or its separate components, and for the removal of gaseous nitrogen oxides, which, being toxic, must undergo neutralization by any known means, for example by passing gas through an alkali solution.

6. It is recommended to use a safe means of initiation for initiating explosive, explosive, pyrotechnic and other hazardous substances and materials, for example, “Safe device for the electric initiation of liquid explosives” according to RF patent No. 2471144, which includes a resistive element, a metal tube and explosive wire inserted directly into the pipe with live fire. In this case, it is possible to produce all explosive materials directly at or near the place of blasting from non-explosive components. For example, in a pipe, use live explosives based on the diazot tetraoxide, and outside of the pipe, explosives of the ASDT type (ANFO) or other types of dynamons [7]. In the case of waterlogged wells, emulsion explosives can be placed outside the pipe. In this case, the pipe beneath the live water supply must have a length greater than the length (depth) of the charged well so that it is not flooded with water, which is pushed (squeezed out) from the well by an emulsion explosive during loading.

7. BB is a very active chemical. They constantly interact with the environment (air moisture, rocks and minerals, water, including in mine workings) [7]. To exclude the contact of explosives with the environment during the formation of charges in the charged mine workings, it is necessary to use protective plastic shells, for example polyethylene sleeves. Placing a sleeve in a borehole or hole is not easy. However, using a rigid pipe, it is much more convenient to carry out this operation, especially when the pipe remains in the mine, resting against its bottom, holding the sleeve. Before lowering into the well, the polyethylene sleeve is put on the pipe in advance, and its lower end is sealed in any convenient way: it is tied, clamped with a metal clip, welded, sealed, etc. For centering the pipe in the well, any known, centering tubes can be used devices, for example flexible petal or curved plastic ones, provided that their design does not interfere with the loading process.

After the sleeve is located in the borehole or hole, the explosive can be fed into the sleeve either manually or using special charging equipment, i.e. forcibly, under pressure, for example, through a charging hose, without fear of any electrostatic, mechanical or other effects on the pipe, as it does not contain explosives at this moment, which is an absolute advantage over the proposals presented in the patents of the Russian Federation No. 2060446 [1] and the Russian Federation No. 2060449 [4].

8. In principle, the tube can be charged with a loose or patched explosive by hand or using charging equipment.

In this embodiment of the proposed method, the following explosives can be used (the first of these explosives is placed in the pipe; the second is outside):

- granulotol, including artificially flooded, and grammonite or dynamon;

- grammonite charged with a pneumatic charger, i.e. compacted, and grammonite or dynamon bulk;

- Ammonite No. 6 GW and grammonite or dynamon;

- a cartridge emulsion explosive charged with an explosive seal in the well with a pneumatic charger, for example, models CB32R, CB42R or CB32RM from Can - Blast Ink. (Canada) and grammonite or dynamon.

Of course, other options are possible, provided that the explosive located inside the pipe has a detonation velocity higher than the detonation velocity of the explosive located outside it.

The initiation of an explosive located inside the pipe is carried out in any known manner, for example, using an additional intermediate detonator (action cartridge) if necessary.

Literature

1. RF patent No. 2060446, downhole charge.

2. Timoshin V.I. Improving blasting in sections of the south of Kuzbass. Materials of the international conference "Blasting - 99". M .: MGGU, 1999, p. 251-254.

3. RF patent No. 2156431, Method for loading a well and design of a borehole charge.

4. RF patent No. 2060449, Column explosive device.

5. Schukin Yu.G., Dobrynin A.A., Galkin V.V. The use of decommissioned ammunition during blasting in industry // Occupational safety in industry. - 1993. - No. 9. - S. 23-26.

6. RF patent No. 2416781, Method for generating explosive charge.

7. Dobrynin A.A. Explosives. Chemistry. Compositions. Security. - M .: Publishing House of the Academy. NOT. Zhukovsky, 2014 .-- 528 s.

Claims (8)

1. A method of forming an explosive charge (EX), comprising a combined charge of two types of explosives, which are arranged concentrically to each other, the central part of the charge being an explosive whose detonation velocity is greater than the detonation velocity of an explosive located in the peripheral part, characterized in that at first a pipe is installed in the recharged mine, then the space around it is filled with explosives, jamming is done or not, after which a liquid explosive is poured into the pipe, for example, based on the diazot tetraox Yes. 2. The method according to p. 1, characterized in that the pipe consists of a material that takes part in the process of explosive transformation, increasing the efficiency of the explosion. 3. The method according to p. 1, characterized in that the surface of the pipe is coated with a composition or material, for example, based on aluminum, which takes part in the explosive transformation process, increasing the efficiency of the explosion, and / or protects the pipe material from the effects of explosives. 4. The method according to p. 1, characterized in that the liquid explosive (LHV) is made directly in the pipe from non-explosive components. 5. The method according to p. 1, characterized in that the used pipe in the upper part has a device for pouring live gas and exhaust gases in the form of tubes whose diameter is less than the pipe under the live air supply coming out of the charge. 6. The method according to p. 1, characterized in that the initiator uses a safe means for electrical initiation, consisting, for example, of a resistive element, a tube and an explosive wire, inserted directly into the pipe with live fire. 7. The method according to p. 1, characterized in that the explosive on the outside of the pipe is located in a plastic sleeve, which is previously put on the pipe under the liquid explosives and together with it is lowered into the charging output. 8. The method according to p. 1, characterized in that the tube is placed loose or patched explosives manually or mechanically.