Explosive means and accessories. Fire method of explosion

Shoot hole method. It is used for small volumes of work, for the extraction of large blocks of building finishing stone, and for the development of particularly valuable minerals. The use of the blast hole charge method allows for better crushing of rock. The disadvantage of this method is the high labor costs for drilling and blasting.

The blast hole method is used in open and underground mining. The blast holes are loaded with TNT blocks, cartridges made of hygroscopic or powdery explosives. The explosive charge in the hole should occupy no more than 2/3 of its length; the upper third of the hole is filled with a stopper (driving). The holes are filled first with a plastic sand-clay mixture, then with sand or drill flour.

Each row of blasthole charges is exploded simultaneously electrically or using a detonating cord: first the row closest to the face is exploded, then the next one, etc. In the presence of delayed-action electric detonators, a given sequence of row explosions is ensured by different decelerations in the rows.

To destroy individual stones, it is advisable to use blastholes not large diameter(25...30 mm), which are drilled to a length equal to 0.5 - 0.75 of the height of the stone. The distances between the holes are taken equal to one or two hole lengths. All charges in the holes explode simultaneously. Single hole charges are also used for uprooting.

Boiler charge method in conditions of transport construction, they are used mainly in open-pit mining and less often in underground conditions, since repeated shooting of the base of holes and wells leads to gas contamination of underground workings and the need to ventilate the working space after each shooting.

It is advisable to use the boiler charge method when breaking ledges, loosening rock openings and blasting for release in well-pierced, non-watered rocks. The chamber charge method can significantly reduce the amount of work required to drill wells and boreholes and sharply reduce the time required to carry out development work compared to the same indicators using the chamber charge method. The disadvantages of the method include a limited list of rocks in which a cavity is formed when shot, as well as the difficulty of measuring the configuration and volume of boilers.

The boiler charge method is used in cases where the explosive charge does not fit in a conventional hole or borehole. In this case, a chamber (boiler) is arranged at the bottom of a hole or borehole, exploding one or successively several lowered small charges.

The boiler charge method provides a large volume of blasted rock and reduces expensive drilling operations.

Method of small-chamber charges (charges in sleeves) usually used when the face height is less than 6 m, mainly in non-rocky soils, as well as during special blasting operations (destruction of foundations, etc.). The length of the sleeve should be 2/3 of the face height, but not more than 6 m, and the distance between the sleeves, depending on the size of the rock pieces, should be from 0.8 to 1.5 m. This blasting method has found application in clearing rock slopes of excavations and half-excavations after massive explosions, during the construction of second tracks railways and when breaking ledges in stone quarries. The method of small chamber charges makes it possible to significantly reduce the volume of drilling work due to the use of natural weak layers in the blasted massif for drilling hoses.

Chamber charge method used for massive explosions for release or collapse when developing pits or channels of significant size. It lies in the fact that vertical wells (pits) or horizontal galleries (adits) are made in the mined rock, from which large charging, or mine, chambers are arranged in the lateral directions to accommodate large concentrated charges. Wells and adits are secured with frames and boards.

The method of chamber charges has not found wide spread for the following reasons: a small yield of blasted rock per sleeve; high labor intensity of tunneling in hard rocks; increased danger carrying out work during the excavation of hoses; increasing the flight range of pieces of rock during an explosion.

The method of chamber charges has several varieties depending on the nature of destruction and movement of soil. This method can be used to produce explosions: for caving in quarries (breaking overburden ledges and mineral ledges) and the collapse of steep rocky slopes when developing near-route quarries; for loosening to form trenches, excavations and channels.

With the development of technology designed for drilling wells, the method of chamber charges in the conditions of transport construction began to be rarely used. The main disadvantages of the method are the high labor intensity of excavation of rock; the possibility of partial destruction of an array of blasted excavations and trenches.

Circuit charges. When developing half-excavations, widening excavations and trenches, as well as when digging tunnels, when the middle part of the tunnel - the core - is first developed, contour charges are detonated after alternate short-delayed detonation of rows of main loosening charges. In this case, the explosive shock wave coincides in direction with the line of least resistance of the main loosening charges, i.e. directed in the direction opposite to the slope (102.6, c). Therefore, slopes are damaged by explosions much less and, just as in the case of preliminary slit formation, traces of wells remain on the surface of the slope.

Parameters of contour blasting when developing rock excavations, trenches and half-excavations. When developing closed excavations and trenches, information about the nature of the occurrence of rocks, their fracturing, degree of weathering, etc. We are often not enough. Therefore, in order to obtain satisfactory results of contour blasting, the issues of choosing the diameter of the wells, the distance between the wells and the density of their loading should be decided based on the results of blasting at the experimental site.

Borehole charge method consists of drilling a series of deep wells (10...30 m long) of large diameter - 200 mm or more along the front of a high ledge. Vertical and inclined wells are drilled with overdrilling below the bottom of the face to a depth of usually 1 to 2 m and loaded with continuous or dispersed charges along the entire height, with the exception of the very top part, in which a face made of loose and small material is placed.

Borehole charges are usually detonated electrically or with a detonating cord, and the network must be duplicated. You can explode without slowing down and with slowing down. Rationally selected deceleration intervals provide better rock crushing and sharply reduce the specific consumption of explosives and the seismicity of the explosion.

Gap charge method They mainly loosen frozen soils. Slots are cut using bar or disc milling machines. Of the three adjacent slits, the middle one is charged; extreme and intermediate gaps serve to compensate for the displacement of frozen soil during an explosion and to reduce the seismic effect. Explosive charges along with a detonating cord are placed at the base of the charging slots, which are then covered with soil using a bulldozer. When blasting, the frozen soil is completely crushed without damaging the walls of the pit or trench.

Overhead charge method used for cutting individual stones (boulders, oversized pieces, etc.), including under water, as well as when destroying metal structures and other special work. To reduce the scattering of fragments, the overhead charge is covered with a layer of cohesive or loose soil (clay mixture, etc.), which is slightly compacted.

A single charge is usually detonated by fire, and several charges by a detonating cord. This method is characterized by increased specific consumption Explosives and scattering of fragments of destructible material compared to blasthole material.

Combined methods. Various options for joint use of basic blasting methods are possible. For example, when digging trenches and expanding excavations and roads in mountains and high ledges, borehole and borehole charges are successfully combined; When crushing rocks on a ledge with a gentle slope, a combination of chamber and small-chamber charges can be used.

Electric blasting method provides for the connection of electric detonators into a single electric explosive network. The network is installed from the electric detonators to the blasting station (another source of blasting). Schemes for connecting charges in an explosive network can be serial, parallel, or mixed.

The electroexplosive method allows you to explode large groups of charges; ensures work safety; makes it possible to preliminarily check the serviceability of blasting means, and therefore obtain trouble-free operation. Disadvantages are the complexity of installing the network and the possibility of premature explosion from stray currents.

Explosion with detonating cord (DS) the least dangerous, since there are no blasting caps or electric detonators. At the same time, it is possible to explode a large number of charges, which are connected to the main blast shield using sections of blast furnace (connected in parallel or in a bundle). The main disadvantages are the impossibility of high-quality testing of the explosive network before the explosion and the need to use other methods of exploding charges (fire or electric).

Explosive means are chosen depending on the methods of exploding charges: with the fire method - a detonator cap, a fire cord, and ignition means. A detonator capsule is a charge of initiating explosives, pressed into a metal or paper sleeve with a diameter of 6.8...7.2 mm and a length of 47...52 mm. The fire cord has a core of powder pulp and a sheath.

Calculation of charges and methods of blasting. Action of charge on environment varies and depends on the location of the charge, its size, the type of explosive, and the physical and mechanical properties of the rock. As a result of the explosion, you can get a compressed (camouflage) cavity, loosen the rock, or throw it outside the funnel.

Explosive sketch method. Until recently, only homogeneous rocks or soils were blasted into the body of a dam or lintel. The method of explosive placement was further developed during the construction of the Nurek hydroelectric power station, where a rock mass of varying composition was laid by explosion, forming a persistent prism, filter and depression in one step.

Mining openings were made in the steep bank to accommodate bank blasting charges, and reinforced concrete pipes were laid along the coastal route for extended release charges. Reinforced concrete and rye retaining walls were built along the shore and stone, pebble and sandy loam were poured, intended for transportation to the cofferdam by explosion.

The total weight of the charges was 265 g. The charges for undermining the bank and crushing the retaining wall exploded instantly. After 0.5 seconds, the charges under the stone and pebble warehouses were detonated, and after 1 second, the charges under the sandy loam warehouse were detonated.

As a result of the explosion, about 50% of the blasted mass fell into the river bed, creating the necessary work front for further expansion of the cofferdam.

Underwater blasting. One of the many applications of explosion energy is the crushing and movement of rocks under water. The need for this operation is associated with the development of deposits of solid minerals on the bottom of seas and oceans, with the construction and deepening of ports and canals, excavation of underwater trenches for pipelines and other types of work. An underwater explosion can serve both to crush rocks with subsequent excavation, and to move them (ejection explosions). Often, despite the high consumption of explosives and the increased volume of drilling, ejection explosions are more economical, since they eliminate expensive excavation and transportation work in underwater conditions.

Influence of the aquatic environment on the destruction process. The main factors determining the effect of water on a blast wave are: dissipation of stress wave energy at the rock-water contact; hydrostatic pressure, preventing the movement of the boundary of the destroyed massif.

Energy loss due to stress wave dissipation in a layer of covering material depends on the ratio of the acoustic hardness of the medium and water

m = с0*c0/с*c,

blasting rock funnel boiler

where c0, c0 and c, c are the density and speed of sound in the medium and water, respectively.

For example, for the granite-water interface at m = 7, 44% of the energy of the blast wave is lost. The greater the acoustic stiffness of the rock, the less stress wave energy is dissipated in the water.

The influence of hydrostatic pressure during the destruction process. At the initial stages of explosion development, it has a positive effect and prevents the process of crack opening, which provides more complete walkthrough stress waves to all points of the array.

But in subsequent moments, when cracks open and the mass moves under the influence of an explosion, hydrostatic pressure plays a negative role, since additional energy is needed to overcome it. At the same time, water at high loading (displacement) rates approaches the properties of an incompressible body (especially in the initial stage) and sharply worsens the efficiency of rock destruction with increasing depth. The maximum efficiency of the explosion is achieved only with free movement of the rock in the direction of the LNS.

Drilling and loading technology. Underwater, techniques similar to those on land are used, adjusted for the higher density of the environment in which the work is performed. Three options for drilling and blasting operations are used: 1) drilling hammers or crawler drilling rigs are used to drill and charge wells (holes); 2) drilling and loading from platforms or floating barges; 3) placing charges at the bottom of the reservoir, i.e. explosion by external charges.

Impact of the explosion on the environment. The main harmful effects of underwater explosions on the environment are: hydraulic shock waves, seismic pressure, contamination with toxic explosives, explosion products and bottom sediments. For small bodies of water, the effects of gravity waves can be significant.

Blasting operations in the extraction of piece stone. Piece stone is a conventional name for products made from natural stone, mainly in the form of blocks in the shape of a parallelepiped rectangle, used in natural form in construction and taken into account during production in pieces (hence the name) or in m3. IN rock By drilling, a deep hole is made, where a charge is placed and detonated. Among the broken pieces of rock, the largest blocks are selected, which are then sawn into slabs. The advantages of this method of stone extraction are that it is extremely cheap. But the disadvantages outweigh this advantage. Firstly, the quality of the mined rock suffers: during an explosion, microcracks appear in the structure of the stone, which affect the strength of the material. Secondly, this method of developing a deposit is extremely irrational, since during an explosion the rock crumbles: large blocks suitable for sawing make up no more than 70%, and the remaining 30% goes to waste.

Blasting operations in the extraction of piece stone. Piece stone is the conventional name for products made from natural stone, mainly in the form of blocks in the shape of a parallelepiped rectangle, used in their natural form in construction and taken into account when extracted in pieces (hence the name) or in m3. A deep hole is made in the rock by drilling, where a charge is placed and detonated. Among the broken pieces of rock, the largest blocks are selected, which are then sawn into slabs. The advantages of this method of stone extraction are that it is extremely cheap. But the disadvantages outweigh this advantage. Firstly, the quality of the mined rock suffers: during an explosion, microcracks appear in the structure of the stone, which affect the strength of the material. Secondly, this method of developing a deposit is extremely irrational, since during an explosion the rock crumbles: large blocks suitable for sawing make up no more than 70%, and the remaining 30% goes to waste.

The charge of the main explosive and the means of detonation are the main elements of the explosive device. Explosive means include initiation means and fuses.

Means of initiation can be divided into means of ignition, means of detonation and means of transmitting the fire and detonating impulse.

fuses, in addition to the initiation means, may include the following parts and mechanisms: target sensor (pressure, unloading, break, etc.), long-range cocking mechanism, self-destruction mechanism, non-retrievable mechanism or element, mechanism remote control, sources of electric current. The fuse of an explosive device contains an algorithm for the operation of an explosive device, starting with its installation, transfer to a firing position, selection of targets (objects), ensuring non-removal, and, if necessary, self-destruction.

The following explosives can be used as the main charge of an explosive device: solid-state in the form of briquettes (for example, TNT blocks); powdered (for example, based on ammonium nitrate); granular (TNT in granules); liquid (for example, aquatol); plastic (plastic); gaseous (various oxygen-fuel or air-fuel mixtures).

By the method of obtaining the initial impulse (explosion) of the main explosive, acting on the means of initiation or directly on the charge of an explosive device, the following methods of detonation are distinguished:

• ? fire;
• ? electric;
• ? mechanical;
• ? chemical.

Their combinations can also be used, for example, electric fire, electromechanical, etc.

Fire method blasting is based on explosive excitation chemical reaction in an initiating explosive by exposure to a flame or a beam of sparks, for example, from a fire hole. To detonate secondary explosives by fire, it is necessary to have: a fire source (which can be a smoldering wick, matches or an electric incendiary cartridge, etc.); fire cord; detonator capsule. To trigger explosives based on propelling, initiating and various pyrotechnic compositions, a beam of fire or a bunch of sparks is sufficient, which can easily be obtained from a fire cord, a chain of match heads, etc.

Electric way explosion is similar to fire, it is based on the detonation of the initiating explosive from the influence of a flame, but the ignition of the ignition composition is carried out using high temperature filament of an electrical circuit. The principle of operation is simple: the current flowing through the incandescent “bridge” causes a flash of the igniting composition, which, in turn, already leads to the activation of the initiating explosive. To use the electric method of explosion, electric detonators were needed, along with electric igniters, current sources and wires. This method is used to produce an explosion at the required time or when it is necessary to simultaneously explode several charges. Explosion control (the so-called switching of the explosive electrical circuit) is carried out using an electrical conductor line, electromagnetic waves, as well as other methods that can control the closure of the explosive electrical circuit at a given point in time or the transfer of the fuse to the firing position.

Mechanical method detonation is based on the explosive detonation of the initiating explosive from an impact. For this purpose, a firing pin (striker) and a primer (detonator capsule) are used. The scheme for initiating a capsule composition is similar to the scheme for firing a shot from firearms, when, under the influence of a spring, the firing pin pierces the primer with its striker and ignites its composition, and the resulting flame force initiates powder charge cartridge.

Chemical method Explosion is based on the initiation of an explosive process as a result of a rapidly or slowly flowing exothermic chemical reaction (a reaction that occurs with the release of heat) of reagents active to each other. This method is often used to switch an explosive circuit in order to transfer a charge from a safe to a combat position after a specified period of time or to self-destruct the charge after a specified time.

Combined method blasting is a combination of the above methods. For example, this includes electromechanical, electric fire methods, etc.

TO means of initiation These include devices designed to excite (initiate) the explosion of explosive charges, directly implementing one or another method of explosion.

Initiation means are devices triggered by a simple initial impulse (impact, friction, puncture, heating, a sheaf of sparks, flame), designed to ignite gunpowder, pyrotechnic compositions and detonate high explosives.

Initiation means are divided into means:

• ? ignition;
• ? detonation;
• ? transmitting the initiating pulse 1.

Ignition means are initiation mechanisms that emit during their operation thermal energy in the form of a ray of fire, heating an incandescent filament, or a spark discharge.

Rice. 4.2. Electric ignition for industrial production:

(1) - wires; (2) - filament bridge; (3) - igniter composition; (4) - sleeve; (5) - plugs

These devices include: impact, pin, grating primers-igniters and electric igniters (Fig. 4.2) of industrial or homemade. The operating principle of electric

Fire igniters are as follows: an electric current passes through the filament, heating it, the pyrotechnic composition ignites and initiates the activation of the main ignition composition, which then forms a beam of fire.

Ignition means are used to detonate propellant explosives, initiating explosives and a number of pyrotechnic compositions. Electric igniters can work as an independent means of initiation, or as one of the elements of an electric detonator, electric capsule, squib, etc. When working at the site of an explosion, remnants of ignition agents can almost always be detected and can subsequently be the object of explosive identification examination.

Detonating means are means of initiation that are used to initiate the detonation of secondary explosives.

These include blasting caps, fuses, and electric detonators. Detonation means usually have all the structural elements of an explosive device: an initiating explosive, triggered by a simple initial impulse in the detonation mode, a high explosive, a shell, so they can be considered as independent explosive devices. Figure 4.3 shows the design of detonator caps.

Exists two types of blasting caps."

• 1) beam, converting a thermal impulse (a ray of fire) into an explosive one;
• 2) impaling, converting a mechanical impulse in the form of a puncture, impact, friction into an explosive one.

In Figure 4.3. (a) schematically shows the structure of beam detonator capsules 1.

In practice, they are most often used beam blasting caps No. 8, which contain combined charges of initiating and high explosives and are used to initiate detonation of the explosive during blasting operations in the national economy. In military engineering, detonator caps KD-8A are mainly used. The detonator caps are mounted in a metal or paper sleeve, and the initiating explosive is additionally enclosed in a steel cup covered with a fabric mesh. Beam detonator caps are initiated by a beam of fire from a fire cord inserted into the cartridge case, which is the so-called incendiary tube used in the fire method of detonation. The detonator capsule can be detonated by a beam of fire from the igniter primer, electric igniter or detonating cord. In addition, an explosion of a detonator capsule can occur from various external influences, such as impact, heating of the housing, dismantling of the detonator, explosion of a nearby explosive charge, or a fall from a height of more than 1.5 m onto a concrete base 1 .

Rice. 4.3. Design of detonator capsules:

• (a) - device of beam detonator capsules: (1) - sleeve;
• (2) - calyx; (3) - silk mesh; (4) - lead trinitroresorcinate;
• (5) - lead azide; (6) - tetryl; (7) - mercury fulminate; (b) - arrangement of electric detonators: (1) - safety shell; (2) - sleeve; (3) - cemented hexagen; (4) - calyx; (5) - lead azide;
• (6) - retarding composition; (7) - igniter composition;
• (8) - incendiary composition; (9) - filament bridge; (10) - frame; (11) - plastic plug; (12) - wires; (13) - tag

Electric detonators are used in the electrical blasting method.

Electric detonators are detonator capsules with an electric igniter inserted into its sleeve, containing an incandescent bridge with an ignition head made of a heat-sensitive pyrotechnic substance (Fig. 4.3. (b)).

When an electric current is passed, the incandescent bridge of the electric igniter heats up, the pyrotechnic composition ignites and produces a beam of fire, which explodes the initiating composition in the metal cup, which leads to the detonation of the main charge of the detonator capsule. The explosion of the latter is the initiating detonation pulse in the main charge of the secondary explosive. When examining the site of an explosion from a detonator capsule, it is relatively easy to detect the remains of an incendiary tube, as well as electrical wires from an electric detonator.

Detonation means should also include intermediate detonators, consisting of a charge of a highly explosive explosive and designed for reliable transmission and amplification of the initial detonation pulse from the detonator capsule to the main explosive charge. Detonation means also include various fuses, consisting of a detonator capsule and an igniter capsule, which convert mechanical energy into an explosive detonation pulse. In addition, many fuses are capable of delaying the explosion time due to the combustion of the pyrotechnic composition of the moderator located between the igniter capsule and the detonator capsule; the most famous example is the fuse of UZRGM hand grenades, which has an explosion delay time of about 3.54 s. Universal igniter device hand grenades shown in Fig. 4.4.

Industrial detonation devices are commonly used to detonate improvised explosive devices, but homemade detonation devices are sometimes found that are extremely dangerous to handle due to a lack of knowledge about their design.

As means of initiating an explosion There may also be means of transmitting the initial explosive impulse, which include devices designed to transmit the initiating impulse in the form of a beam of fire (fire cord) or a detonation impulse (detonating cord). A fire cord can directly initiate propellant and initiating explosives, as well as various pyrotechnic compositions, and a detonating cord can also initiate medium-sensitive secondary explosives (dynamite, hexogen, etc.).

• (1) - detonator capsule; (2) - moderator; (3) - connecting sleeve; (4) - safety pin; (5) - mainspring; (6) - impact mechanism tube;
• (7) - guide washer; (8) - drummer; (9) - striker washer; (10) - igniter primer; (11) - retarder bushing; (12) - release lever

To activate the explosive device, it has fuse, which, in addition to the initiation means, may include the following parts and mechanisms; target sensor (pressure, unloading, break, etc.); long-range cocking mechanism; self-destruction mechanism; anti-removal mechanism or element; remote control mechanism; source of electric current. The fuse of an explosive device contains an algorithm for the operation of an explosive device, starting with its installation, transferring to a combat position, selecting targets (objects), ensuring non-removability and, if necessary, ending with self-destruction. It is the fuse that forms and gives the command to detonate the warhead of the explosive device and, on the same command, initiates the explosion. The fuse can be built according to a simple scheme: an electric detonator, a current source and a switch (target sensor) or a detonator capsule and a firing pin with a trigger mechanism; or it can be a fairly complex device with electronic circuits.

Knowledge of the principles of operation of fuses and their technical implementation will allow employees of the Russian Ministry of Internal Affairs to successfully act when criminals use means of committing crimes that are particularly dangerous to public safety. Let's take a quick look basic mechanisms factory fuses and available data on the improvised fuses used.

Target sensor designed to record the moment in time of the impact of a target (object) on a selected area of ​​terrain, space or objects. The target sensor ensures that the explosive device operates as a standby munition, when it is triggered only as a result of a strictly defined target impact. The target sensor always provides for the selection of various influences. For example, in a number of mines, the target pressure sensor is designed for a load of at least 10 kg with an exposure time of at least 0.5 seconds. This, on the one hand, ensures a given level of noise immunity, and on the other hand, the explosive device is oriented towards certain type goals 1.

By operating principle target sensors are divided into mechanical, electromechanical, electronic (including those responding to changes in magnetic or electric field, illumination, etc.) and chemical.

Depending on the a way to record the impact of a target sensors can record: the moment the target impacts certain items or objects (turning on electrical appliances, opening a door, moving an object, changing the position of an object, etc.); starting to move or stop the target; moving a target through a certain area of ​​terrain or premises; changes in pressure, degree of illumination, magnetic, electric, acoustic fields, etc.; other changes in the situation.

Pressure sensor purpose is designed for mechanical impact with a certain force and duration. Figure 4.5 shows technical solutions target sensors for an anti-personnel mine in a wooden PMD-6 case and an improvised explosive device consisting of two metal plates made of tin with punched holes and protruding sharp edges, insulated with a thin dielectric film. When you press the spring-loaded cover of the PMD-6 mine, the safety pin is pulled out from the MUV-2 universal mine fuse (Fig. 4.5 (a)) and the detonator cap is triggered. When stepping on the upper metal plate (Fig. 4.5 (b)), the sharp edges pierce the dielectric film and the electric detonator circuit is closed.

• (a) - anti-personnel mine PMD-6: (1) - wooden mine cover;
• (2) - combat pin MUV-2; (b) - homemade target pressure sensor: (1) - metal sheets with sharp edges from holes; (2) - dielectric film; (3) - power supply of the explosive device; (4) - electric detonator; (5) - warhead of an explosive device

Unloading sensor designed to be activated when a load is removed from it. Figure 4.6 shows one of the standard schemes unloading sensors used in the designs of improvised explosive devices, and the MS-3 surprise mine 2 .

Rice. 4.6. Explosive device with unloading target sensor 3: (a) - homemade explosive device: (1) - first electrode; (2) - second electrode; (3) - a piece of rubber; (4) - power supply; (5) - electric detonator; (6) - warhead of an explosive device; (o) - industrial surprise mine

Tension sensor target is triggered when the target acts through a trip wire (thread, rope) stretched on a walking path, in a corridor, etc. When a person touches the tripwire, the pin is removed from the fuse trigger or the electrical contacts of the detonator are closed.

Break sensor The target is set in the same way as a tension one, with the only difference being that here the formation of a signal to detonate occurs when the tension wire breaks. A factory-made explosive device typically uses a thin electrical wire with a special electronic circuit. If the wire breaks, the electrical circuit of the detonator closes. Figure 4.7 schematically shows the designs of easy-to-manufacture homemade break target sensors used by militants of gang formations during hostilities in the North Caucasus in the 90s of the 20th century.

Rice. 4.7.

production 1:

• (1 and 20) - electrodes; (3) - stretching; (4) - power supply;
• (5) - electric detonator; (6) - warhead of an explosive device

Inertial sensor(position sensor) is activated by moving it in any direction or tilting it in any plane (depending on the design). Figure 4.8 shows a typical liquid mercury target sensor, which is often used in homemade booby traps. When a homemade mine-trap is tilted, the mercury ball moves inside the glass body of the fuse and, in a certain position, bridges the contacts of the detonator's electrical circuit.

Seismic target sensor registers the movement of people, equipment and animals by processing seismic signals in the ground. The sensor consists of geophones that respond to seismic ground vibrations, an analytical device that selects interference and false signals, and also determines the distance and direction of movement of the target. These sensors are widely used in factory-produced anti-personnel and anti-tank mines. For example, seismic sensors of modern anti-personnel mines make it possible to highlight the target (the movement of an infantryman in a given direction) against the background of a tank moving nearby.

Rice. 4.8. Explosive device with mercury position sensor 1:

(1) - mercury; (2) - electrodes; (3) - power supply; (4) - electric detonator; (5) - warhead of an explosive device

Magnetic target sensor reacts to the appearance near it of products containing metal with magnetic properties, for example, to the passage of an armored car or the passing of a metal detector sensor over it. These sensors are widely used in factory-produced anti-vehicle mines.

Optical sensor incorporates photo relays or LEDs that respond to changes in illumination in a wide range of electromagnetic radiation, including in the invisible zone of the spectrum. For example, an explosive device (or only a fuse) is placed in a case, when opened, light hits the LED, the detonator circuit is closed and the explosive device is detonated. In addition, sensors can be used that change the value of the photocurrent depending on the level of illumination of a particular object, and when the specified value of the current is reached, the fuse is triggered.

Temperature, barometric, wind, acoustic, electromagnetic and other sensors are quite rarely used for criminal purposes, and therefore are not considered here. However, it should be noted that determining the type and type of target sensor at the stage of inspecting the scene of an incident when an explosive device is detected will make it possible to protect the participants of the operational investigation team.

Using only target sensors in fuses does not allow in practice to create a sufficiently reliable and safe explosive device to handle, therefore industrial fuses (less often homemade) often contain additional mechanisms: long-range arming, deceleration, self-destruction, target counter.

Long-range cocking mechanism designed to place an explosive device in a firing position after some time has passed after the last command or human action. This is a kind of fuse against the miner's error, which makes it possible to move to a safe distance. The long-range cocking mechanism blocks the detonator actuator or the detonator itself for a certain time, preventing the last link in the chain of commands to detonate the detonator from operating.

As an illustrative example, let us consider the principle of operation of the long-range cocking mechanism of the MUV-2 universal mine fuse. Here, the long-range cocking mechanism is a plate (metal element) made of soft metal, most often lead, a loop of steel wire (cutter) spot welded to the rear of the firing pin, and a mainspring (Fig. 4.9).

Rice. 4.9.

(1) - MUV-2 assembled; (2) - body; (3) - rubber cap; (4) - metal element; (5) - bushing; (6) - T-shaped combat pin; (7) - striker with cutter; (8) - mainspring; (9) - safety pin

After the explosive device is installed on the tripwire, the upper safety pin is removed from the MUV-2 by the ring. Next, the firing pin, under the action of the mainspring, tends to move toward the primer, and the cutter begins to cut through the metal element. Depending on the temperature, this process lasts different time at room temperature - 15-20 minutes, in the cold - 40-60 minutes. After cutting the metal element, the firing pin will rest against the firing pin and the fuse will move into the firing position. If the combat pin is now removed, the explosive device will immediately detonate. If the metal element has not yet been completely cut through and at this moment the combat pin is pulled out, then the explosive device will not immediately detonate, since the firing pin will not be able to strike the primer. In homemade explosive devices, an electronic timer is sometimes used as a long-range arming mechanism, connected to the open circuit between the target sensor and the electric detonator. When a signal is received from the target sensor, the timer will begin counting down and after a specified period of time will close the electric detonator circuit to detonation. Thanks to this, if the target sensor is triggered by interference or there is an error when installing an explosive device, the perpetrator has time to disconnect the power from the detonator or leave the dangerous territory.

Deceleration mechanism used to turn on the target sensor at an estimated time (from fractions of a second to several months). An explosive device can be planted at the site several days or even months before the combat situation is released. For example, a magnetic sensor designed to be triggered when a door is opened will be included in the electrical circuit of the fuse after 12 hours, which means that only 12 hours after installation the explosive device will go into target standby mode, and before that time opening the door will not cause an explosion 1 .

Non-retrievable mechanism designed to detonate an explosive device when attempting to defuse it or remove it from an object. For this purpose, various devices included in the detonator circuit can be used. For example, an anti-personnel mine with a discharge fuse is placed under an anti-tank mine - a surprise mine. When an anti-tank mine is removed, a surprise mine is detonated.

Target counter gives a signal to detonate an explosive device after moving a specified number of targets near it. For example, when installing an explosive device to open a door, an explosion will occur after the tenth opening, which can lead to the death of law enforcement officers who arrived to inspect the scene and were not convinced of the safety of this action. The target counter is usually used in factory-made explosive devices with a proximity fuze.

Fuze control mechanisms (lines) are designed to change the state of an explosive device remotely at any time, regardless of the operating mode of the fuse. Control can be achieved by a radio channel, wired lines, mechanically, or an optical channel. Using these control lines, the explosive device can receive the following commands:

• ? transfer to a combat position, i.e. turning on the target sensor, starting the clock mechanism, etc.;
• ? carrying out an explosion immediately, despite the established operating algorithm (to prevent the removal of the explosive device in the event of a change in the operational situation);
• ? transfer to a safe position;
• ? neutralization without damage to the mining object (the explosive device or only the fuse is destroyed by a special squib without detonation of the main charge) 1.

Radio channel makes it possible to control an explosive device at a distance without carrying out preliminary work on laying and masking wires or special mechanical devices. As a radio channel in modern factory-made mines, special encoded receiving and transmitting systems are used, which have high security when transmitting commands in conditions of interference and false signals. In improvised explosive devices, amateur stations of any class are used with a command receiving distance of 10-20 m. To trigger fuses when using radio channels in improvised explosive devices, the following are often used: radio receivers tuned to a certain frequency; receiving devices for radio toys included in the electric detonator circuit; receiving parts for car alarms, etc. Radio fuses of simple designs are unreliable; they can react to radio interference and false signals, which can cause an unauthorized explosion, so it should be borne in mind that exposing such fuses to a strong noise signal from a Perseus-type radio jammer will most likely cause it to be triggered without permission.

Wired lines control lines usually reach tens and hundreds of meters in length. In recent years, more and more wide application they find optoelectronic control lines, the influence of which from electrical noise (lightning discharges, stray ground currents, etc.) is negligible. The use of wire lines requires conditions, effort and time to lay and disguise them. After an explosion at the scene, they are easily detected 1.

Mechanical methods control of an explosive device includes a wide variety of devices and devices - from the cord, with the help of which the combat pin is removed, to the use of a sniper shot and the closing of the safety element with a bullet (Fig. 4.10). The latter option was often used by militants of gangs in the Chechen Republic.

Rice. 4.10.

• (1) - electrodes; (2) - insulating film; (3) - fired bullet;
• (4) - power supply; (5) - electric detonator;
• (6) - warhead of an explosive device

As optical channels For control, laser and beam sources and receivers can be used, the operating principle of which is based on the receiver converting the control optical (infrared) signal into an electrical one and feeding it into the detonator circuit. In practice, there are known cases of using laser sights in improvised explosive devices.

As an example, consider the algorithm of action of the M-619 proximity fuse (USA). It is used to destroy moving equipment and includes in its design a seismic sensor (geophone), a source of infrared radiation and a signal processing and control unit. Its operating principle is as follows; The infrared source is located on one side of the road, and on the other side an infrared radiation receiving device is installed, located next to the explosive device. Thus, the device operates in target waiting mode. The detonation occurs as follows. Ground vibration from the movement of a target approaching the charge is perceived by a geophone, which converts it into electrical signals transmitted to the control unit. The infrared receiver automatically starts working from the control unit and the explosive device is switched to the firing position. When the target crosses the infrared beam, the explosive device is triggered and the target is hit. In this case, a targeted explosive device is used (for example, domestic mine MON 50).

Homemade devices with such a complex mechanism of action are almost never found. Two types of homemade radio-controlled explosive devices are often used for criminal purposes. First- the simplest one, it uses a control unit and a radio-controlled toy receiver, which play the role of a radio fuse and radio transmitter. The disadvantages of this method of explosion are: short control distance; there is a constant danger of the fuse being triggered by some extraneous radio signal. It should be borne in mind that these explosive devices are extremely dangerous to handle and self-explosions often occur during their installation.

Second type uses radio fuses cellular communication. Here, a cell phone is used as a radio receiving device, the signal of which closes the microrelay contacts when calling. Through these contacts, electric current is supplied from portable batteries to the electric detonator. Recently, as a long-range cocking mechanism to protect against unauthorized operation cell phone When an explosive device is installed in the firing position, an electronic timer is sequentially switched on between it and the actuating element. The signal from the radio-controlled element starts the timer countdown, and the timer signal triggers the fuse. Sometimes, instead of an electronic timer, an electromechanical safety element (an electric motor with two contacts) is used. In this case, if, when installing an explosive device, the timer was triggered by a false signal (interference), then the criminal has time to break the detonator circuit or move to a safe distance 1 .

Fedorenko V.A., Kolotushkin S.M. Decree. Op. P. 100.

Means and accessories for fire blasting.

The fire method is used when exploding single explosive charges or for exploding series of charges at different times, when the explosion of one of them cannot damage another charge or another series.
The essence of this method is that the explosion of the detonator capsule occurs from a beam of sparks produced by a fire cord, the end of which is inserted into the sleeve of the detonator capsule. As a result of the explosion of the detonator capsule, the explosive charge explodes.

The advantages of the fire method are:

• simplicity and speed of execution
• absence of complex and expensive devices

Disadvantages of this method:

• relative danger to the explosive due to its direct presence at the location of the charges during ignition of the fire cord
• not completely reliable explosion due to the inability to check the quality of the fire cord used in each incendiary tube and the quality of the incendiary tube
• the impossibility of simultaneous explosion of a series of charges, no matter how carefully the lengths of the sections of the fire cord are measured, therefore, when exploding several charges, they must be located at such a distance from each other that the explosion of one charge does not damage neighboring charges

In the fire method, the charges are detonated by an incendiary tube consisting of a detonator cap and a fire cord. Incendiary tubes come from industry in ready-made form (incendiary tubes with a fire cord in a ZTP plastic sheath) but can also be manufactured by the military.

To make incendiary pipes in the army and ignite them, you need:

• detonator caps
• fuse
• ignition (smoldering) wick
• sharp knife
• crimp

Capsules - detonators

Detonator capsules are used to initiate (excite detonation) explosive charges. The troops use two modifications of it for demolition work - KD No. 8-A and KD No. 8-M. The difference between them is the body material (aluminum or copper) and the type of initiating explosive used.
The dimensions of both detonator capsules are the same - length 47 mm, diameter 7 mm.
On one side the CDs are open and the end of the fire cord is inserted there.

In the picture (from top to bottom): KD No. 8-A KD No. 8-M KD No. 8-M (educational inert) KD 8-A (imitation)

The detonator capsule is a sleeve with an internal diameter of about 6.5 mm, closed at one end and open at the other, into which 1.02 g of high-power high explosive explosive (tetryl, hexogen or PETN) is pressed. Then, in the sleeve, approximately in its middle, a cup with an initiating explosive is pressed, as if inverted, also aluminum, containing: from below (from the high-power blasting explosive side) - 0.2 g of lead azide, from above - 0.1 g of teneres. About half of the sleeve on the open end side is hollow. The cup on the side of the hollow part of the cartridge case has a small hole, covered from the inside of the cup with a thin silk or nylon mesh, which protects the initiating explosive from spilling out of the CD. The closed end has a cumulative recess, in the direction of which the detonation impulse is much stronger than in other directions.

Detonator capsules are extremely sensitive to minor external influences. They can easily explode from impact, spark, heat, friction against the initiating composition, as well as from flattening of the cartridge case, so detonator capsules should be handled very carefully. You cannot drop them or hit them. Detonator capsules should be protected from moisture, especially those filled with mercury fulminate; they should be stored in dry places, separate from explosives.
Detonator capsules are stored and transported in cardboard boxes of 50 pieces or metal boxes of 100 pieces per vertical position butt up.

CDs are delivered to blasting sites in the same packaging or in special wooden cases of 10 pieces, which are carried in bags separately from explosives. It is forbidden to carry CDs in pockets.

Detonator capsules are considered unusable if:

• through cracks and bruises on the sleeve
• powdering the walls of the sleeve with the initiating composition
• oxidation in the form of large spots or continuous deposits on the cartridges

Detonator capsules with the indicated defects are prohibited from being used for blasting operations.

Fuse

The fire cord (OSF) is intended to initiate an explosion of detonator caps in incendiary tubes and ignite black powder charges.

Depending on the type of sheath, the fire cord is produced in three brands: OSHP, OSHDA, OSHA.
In the name “OSHP” the letter “P” denotes the material of the outer shell. The outer diameter of the OSHP is 5-6 mm. The burning speed of OSH in air is 1 m/s or slightly less (60 cm of OHP should burn in 60-70 s). The OSH also burns under water, where its burning rate is higher than in air, and the deeper, the faster the cord burns (due to the increase in pressure at depth). At a depth of 5 m, the increase in the burning rate of OSH is usually 20-30%, but sometimes can reach 50%. OSH can burn under water and at greater depths, but then its burning rate is unpredictable, breakdowns are possible, i.e. almost instantaneous burning of sections of the cord, therefore, at depths of more than 5 m, the OSH is not used. OSHP is stored in coils of 10 m of different diameters; the ends of the cord in the coils are usually impregnated or sealed with wax to prevent the powder core from becoming damp if the cord is not stored satisfactorily.

Already removed from the supply of troops, but in wartime they can be used (since they are available in the civilian industry) fire cords of the OSHA and OSHDA brands - asphalted and double asphalted, which differ from the OSHP sheath. OSHA has a sheath of cotton or linen threads impregnated with asphalt mastic (tar), so the color of the cord is gray-black. Despite this impregnation, this cord is not used in damp places under water.

OSHDA, with the same diameter as OSHA, and without differing in appearance, has a double asphalt shell, therefore its waterproofing abilities are higher than those of OSHDA, and the OSHDA cord can be used under water. All characteristics of OSHA and OSHA are the same as OSHP (except for the non-use of OSHA under water).

Fire cord OSHP-MG (slow burning) in a grayish-blue plastic sheath is also produced. Its core is not powder, but has a multi-component composition of yellow color. The burning speed of OSHP-MG is 1 cm per 3 s. This cord is not used independently, only as part of some industrially manufactured incendiary pipes, because OSHP-MG is more expensive to produce, and since its combustion intensity is lower than that of the considered analogues, it is more difficult to ignite it in the usual way.

To check the burning speed of the cord, cut off 2-3 cm of the cord from the end of the circle and destroy it. Then they cut off one piece 60 cm long and set its core on fire, measuring the burning time of the segment using a stopwatch. The burning time of the segment should be 60-70 seconds. A cord that extinguished during testing and showed a burning rate of less than 60 and more than 70 seconds is not allowed for use.

Ignition (smoldering) wick

An ignition (smoldering) wick is used to ignite a fire cord.
Characteristics of ignition wick:

• conditions of use: in dry places
• color - light yellow
• diameter - 6 - 8 mm.
• smoldering speed - 1 cm in 1 - 3 minutes

The ignition wick is a bundle of cotton or linen threads woven into a cord and impregnated with potassium nitrate.
When working with igniter wick Special attention It is necessary to pay attention to its good connection with the fire cord, since a poor connection leads to failures.

Combined crimp

Combined crimping is used to crimp the detonator capsule onto the fire cord.
Comprises:

Incendiary pipes

Incendiary pipes come from industry in finished form, but can also be manufactured by the military.

Industrial Lighting Tubes

The following brands of standard igniter tubes are available:
ZTP-50. The igniter is mechanical or grating. Burning time 50 sec. (underwater 40 sec.). The cord color is white.
ZTP-150. The igniter is mechanical or grating. Burning time 150 sec. (underwater 100 sec.). The cord color is white.
ZTP-300. The igniter is mechanical or grating. Burning time 360 ​​sec. (underwater 300 sec.). Cord color is blue.

There are two slots at the end of the igniter body: deep and shallow. The deep slot is intended for installing the pin in the safety position; when placed in this slot, the pin cannot be pulled out by the ring. The pin is transferred into a small slot before the ignition tube is activated; The pin can be easily pulled out from the small slot by the ring.

When using igniter tubes with a mechanical igniter, you must:

• make sure the pin is in a deep slot
• screw the igniter onto the nipple of the igniter assembly of the igniter tube
• screw the detonator cap into the charge ignition socket
• lift and turn 900 to move the pin from a deep slot to a shallow one
• holding the igniter by the body with your left hand, pull the pin by the ring with your right hand (while pointing the igniter rod away from you)

When the pin is pulled out, the firing pin, under the action of a spring, punctures the igniter capsule, which ignites the fire cord. A bunch of sparks from the fire cord, after burning along its entire length, causes an explosion of the detonator cap.

Making incendiary pipes in the army

In the manufacture of incendiary tubes (ITUs), only OCs that have been previously tested for burning rate are used.
They check it like this: cut off the end 10 - 15 cm from the coil (if the OS coil is supposed to be used completely in this episode of blasting, the second end is cut off in the same way), then measure, cut and ignite a 60 cm long OSH coil, timing it in the second hand ignition time.
If the segment burns within 60 to 70 s, the OSH is suitable for use; if it burns faster or slower, the cord is considered unusable, and the entire coil is destroyed by burning.

When manufacturing an EP at a blasting site, it is necessary, first of all, to prepare a section of the OB of the required length. The length of the Osh segment is determined when exploding one explosive charge by the time required for the explosivesman to move to a safe distance from the charge (or to a shelter), and when several charges are detonated - by the time required to ignite all the incendiary tubes and for the subsequent withdrawal of the explosives to a safe distance.

To explode charges located, for example, in the ground, the length of the OSH segment must be such that the end of a cord with a length of at least 25 cm protrudes out of the ground for ease of ignition.

Using a dry, sharp knife (preferably on a wooden lining and in one motion so as not to soak the cut and spill gunpowder from the core of the gun), cut a piece of fire cord of the required length so that at one end the cut is at a right angle, and at the other at an angle as much as possible more acute, but not less than 45°. The sharper the flammable end of the gun is cut, the more the powder core is exposed, the more conveniently the match will rest on it when ignited, and the more reliably the gun is ignited.
Then the CD is removed from the box and its suitability is checked by inspection. If defects are found in it, it is rejected. If a speck gets into the CD, it is removed by lightly tapping the muzzle on your fingernail. It is forbidden to remove specks from the detonator cartridge with any objects (even a straw), so as not to cause detonation of the initiating explosive, and also to blow them out, since in this case moisture can get into the detonator capsule, which can moisten the core of the cord, and this will lead to failure of the incendiary tubes.
The end of the OS, cut at a right angle, is carefully inserted into the CD sleeve until it stops at the cup. The cord should be inserted into the sleeve easily, without pressure and rotation, which can lead to an explosion of the compressor. If the cord fits into the sleeve too loosely, wrap the end with one layer of insulating tape or paper.

After this, to secure the CD to the fire cord, the CD is crimped. To do this, take the cord in your left hand and, holding the CD with your index finger, apply a crimp with your right hand so that its lower surface is at the level of the sleeve cut, and it is even more convenient that the sleeve cut protrudes 1 - 2 mm below the crimp surface - then it is easier to control uniform compression level.

Then the CD sleeve is crimped, after each pressing, opening the crimp and slightly turning the ignition tube in the open crimp or turning the crimp around a stationary held EZ. With each press, increasing the force, it is necessary to achieve the formation of an even annular neck on the CD sleeve, which ensures the strength of the connection between the CD and the OSH. Do not apply crimping pressure to the place where the explosive is placed.

The CD can only be crimped by crimping. If there is no crimping, then the end of the OC inserted into the CD should be wrapped with insulating tape or (in the absence of tape) paper so that the cord does not fall out of the sleeve under the influence of its own weight.

The correct articulation of the CD with the OS is a very important condition that ensures failure-free blasting, therefore, when manufacturing the EP, the following must be especially carefully observed:

• perpendicularity of the trimming of the end of the OSH introduced into the CD relative to its axis
• bringing this end of the cord tightly to the CD cup
• quite strong, but without pinching, compression of the KD sleeve onto the OSH

If the end of the cord inserted into the CD sleeve is cut obliquely or is not brought to the cup, then the core of the cord will be located at some distance from the hole in the cup, and sparks flying from the end of the cord when it burns out, overcoming the air gap between the powder core of the cord and the initiating explosive substance of the detonator capsule will lose their strength (force and burning sensation) and may not initiate detonation of the detonator.
Weak fastening of the cord in the CD sleeve creates the possibility of the end of the cord moving away from the cup when handling the incendiary tube.
On the contrary, with very strong compression with the formation of a deep neck on the cartridge case, the powder core of the gun can be displaced (broken) by the highly compressed shell of the cord, and its combustion will end at the point of rupture; the CD explosion will not occur.
When using incendiary tubes in damp places and during underwater explosions, the junction of the cord with the CD is covered with insulating tape.
If the incendiary tube is not used immediately, especially in damp weather, its free end is also covered with electrical tape, which is removed only before using the ET. If in this case there is no electrical tape, the EZ should be made several centimeters longer than the calculated value, so that before use, these few centimeters of the OZ, which could become damp at the end even during short-term storage, for example, in a wet bag, can be cut off.

It is impossible to make incendiary tubes in places where explosives are stored and issued, as well as closer than 25 m from the location of explosives and charges from them. OSh, KD and ZT cannot be placed on the ground even in dry weather. In rainy weather and snowfall, incendiary pipes should be made under a canopy, in tents or under a raincoat. If several blasters are engaged in the manufacture of incendiary pipes, they must be at least 5 m apart from each other.

Ignition of igniter tubes

Ignition of the fuel with matches is carried out as follows.
After bringing the charges to 1 degree of readiness (in this case, this is inserting the 3D into the charges), on the command “Get ready,” you need to turn your left hand with the palm facing you, move the index finger about 1 cm from the middle one, and move the middle finger the same amount inside the palm. Then you need to insert the OS under the middle finger on the extreme phalanges of the index and ring finger, press your middle finger against them so that the obliquely cut end of the matchstick lies on the first phalanx of the index finger, without protruding beyond the finger more than 5-7 mm (otherwise, when ignited, the protruding part of the matchstick will bend and the match head will move away from the core of the matchstick). Then you need to apply an unwetted match with a good head with its head to the core of the cord, pressing it thumb Tight enough, but not too tight so as not to break. At the same time, press not at the head itself, but at a distance of 1 cm or a little more (for ease of ignition).

After this, the blaster should make sure that during these manipulations the charge has not fallen out of the ignition socket of the charge, but is in it all the way, and raise his right hand with the box of matches up (a left-handed person can do everything “mirror”, i.e. instead right hand work left and vice versa). This is a traditional signal from the blaster to the blasting supervisor about readiness. On the “Fire” command, the explosivesman, moving the box along the match, ignites the EZ, once again makes sure that it is correctly inserted into the charge, stands up (if he made it from his knees) and takes a step back from the charge. This is a signal to the work manager that this bomber has ignited his explosive device. If the detonator ignites several CBs, then he should stand at the last one.

In the event that the blaster ignites several ES or if for some reason he fails to ignite the ES from the first match, the blaster, even before the command “Get Ready” or at the beginning of its execution, takes several matches into his lips in order not to waste time getting them out from the box during subsequent ignitions of the ignition.

Engineering training. Explosives.

General provisions. Main characteristics of initiating, throwing, high explosives. High explosiveness and brisance.

Engineering training. Electric blasting method.

Features of the electric blasting method, basic means.

[ all articles ]

The following methods are used to detonate explosive charges:

Fire;

Electric;

Mechanical;

Chemical.

For fire and electrical explosion methods, explosion using a detonating cord can also be used. Mechanical and chemical methods blasting are widely used in explosive devices for various mines. These blasting methods, as a rule, are not used during blasting operations. The teacher shows the means and accessories for the fire method of explosion, explains their structure and the rules for their use.

The fire method is used for exploding single explosive charges or for exploding series of charges at different times, when the explosion of one of them cannot damage another charge or another series.

With the fire method Explosion of charges is carried out by an incendiary tube consisting of a primer - a detonator and a fire cord.

To make an incendiary pipe in the army and ignite it, you need:

Detonator caps;

Fire cord;

Ignition (smoldering) wick;

Regular matches or demolition matches (smoldering)

Capsules - detonators explode from a bunch of sparks from a fire cord (in the fire explosion method), from the flame of an electric fuse (in the electric explosion method) or from the explosion of a detonating cord (if it is used in the fire or electric explosion method).

Detonator capsule No. 8-A is a cylindrical aluminum sleeve open at one end, in the lower part of which high-power high-power explosives (RDX, ten, tetryl) are pressed, and initiating explosives (lead azide and teneres) are pressed on top. The detonator primer charge is covered on top with an aluminum cup with a round hole in the center, covered with a silk mesh. Detonator capsules No. 8-M, No. 8-S, No. 8-B can also be used, having, respectively, a copper, steel or paper sleeve with a brass or copper cup, and mercury fulminate as the initiating explosive.

KD No. 8-A are very sensitive and dangerous to handle; they can explode from impact, friction and heat. Detonator capsules are stored and transported in special cases separately from explosive charges.

The SMP miner's bag is designed to carry explosives and explosion accessories. mining, and demining as well as tools for demolition.

The SMP kit includes:

1. combined crimping;

3. pencil case for CD No. 8-A;

4. case for fuses MD-5M;

5. spool of wire;

6. flyer with twine and threads,

7. clip for fuse mechanisms;

8. insulating tape,

9. pencil case with a set of safety pins and carbines;

10. matches;

11. explosive (TNT, etc.);

12. ruler;

13. flat board

The fire cord is designed to initiate a pressure explosion in incendiary tubes and ignite black powder charges. The fire cord consists of a powder core with one guide thread in the middle and a number of inner and outer braids and sheaths. The outer diameter of the cord is 5-6 mm.

Fire cord is available in three main types:
*OSHA - asphalted fire cord with cotton braid. Its color is dark gray. Burning speed 1cm. per second (plus minus 7%). Diameter 4.8-5.8 mm. Supplied in coils 10m long.

*OSHDA - double asphalt fire cord with cotton braid. Its color is dark gray. Burning speed 1cm. per second (plus minus 7%). Diameter 5-6 mm. Supplied in 10m long coils. Recommended for use in damp areas and under water.

*OSHP - fire cord in a plastic sheath. Its color is white. Burning speed 1cm. per second (plus minus 5%). Diameter 5.0 mm. Supplied in coils 10m long. Recommended for all occasions. A modification of it is also available with a burning speed of 0.278 cm per second. This cord has a blue sheath color.

Bickford cord was used in demolition before the outbreak of World War II. The massive use of demolition during the war, especially by poorly trained personnel, clearly revealed the previously inconspicuous, but very significant shortcomings of the fuse cord:

1. The cord goes out under water.

2. The burning rate of the cord is unstable due to the characteristics of the powder pulp (different degrees of moisture in different areas, different densities of different areas), which makes it difficult to calculate the length of the cord to detonate the charge after a given period of time).

3. The open ends of the cord must be protected from moisture, otherwise the cord may fail when ignited.

4. Asphalt cracks at low temperatures and does not provide a tight seal for the cord and protect it from moisture.

5. In cords made during the war, due to a decrease in quality, cases of so-called “lumbago” have sharply increased, i.e. instantaneous transfer of flame on some part of the cord, which led to premature explosions of explosive charges.

These significant shortcomings of the Bickford cord already in the second half of the war prompted engineers to create a new type of cord for the fire method of explosion. As a result of first partial changes in the design, and then more radical ones, a new type cord, which was named "Fuse".

First of all, they abandoned the powder pulp from ordinary black powder. It was replaced by a complex pyrotechnic composition based on nitroglycerin powder. This ensures stable burning of the cord even under water at depths of up to 5 meters (in reality and at much great depths). The stopin was replaced with a guide thread twisted from three cotton threads, each of which has a different impregnation. This ensures fairly accurate control of the burning speed of the cord, prevents combustion attenuation and prevents the phenomenon of lumbago. The type of braid has changed from radial to diagonal, and adjacent layers of braid have different weaving directions, which provides higher strength and flexibility of the cord. The number of layers of braiding became not two, but three or five. Asphalt began to cover not only upper layer braids, and intermediate ones. A cord with five layers of braid became known as a “double asphalting cord.” Somewhat later, in the mid-fifties, the outer layer of asphalt was replaced with plastic.

A fire cord cannot be extinguished unless the integrity of the guide thread is damaged, unlike a fire cord. This is impossible in principle.

The fire cord is designed to transmit the flame force to the pressure chamber from the blaster through a strictly defined period of time. The time interval from the moment of ignition of the end of the cord to the moment of explosion depends on the length of the cord. Standard Russian fire cords have a stabilized burning rate of 0.33 or 1 cm per second. Main brands of fire cord:

OSHP. The shell is plastic, grayish-white. Cord diameter 5-6mm. burning speed in air is 0.86 - 1 cm per second. When burning in water deeper than 5m. the burning rate increases slightly. A burning cord under water does not go out, provided that the other end is closed hermetically.

The OSH with a blue shell burns at a speed of 0.3 -0.34 cm per second.

OSHA. Shell made of cotton asphalted threads. The shell color is dirty gray with black spots. Characteristics similar to OSHP, but not recommended for blasting in water.

OSHDA. The cord is similar to OSHA, but has a double sheath and can be used for blasting in water.

All fire cords are produced and supplied to the troops in 10-meter coils. The required amount of cord is cut from the coil

A piece of fire cord connected to a detonator cap is called a “fire tube.” To produce an explosion, the incendiary tube is inserted with a detonator cap into a specially prepared explosive charge socket, the open end is ignited and after a specified period of time an explosion occurs.

In all cases, the minimum length of the fire cord in the igniter tube cannot be less than 50cm. (50-55 sec. burning). When working to protect bridges from ice drift, specially trained demolition workers can use incendiary tubes with a cord 10 cm long.

An ignition (smoldering) wick is used to ignite a fire cord and is a bundle of cotton or linen threads woven into a cord with a diameter of 6-8 mm and impregnated with potassium nitrate. The wick smolders at a speed of 1 cm per 1-3 minutes, depending on the wind force.

When working with the ignition wick, special attention must be paid to its good connection with the fire cord, since a poor connection leads to failures. The ignition wick must be protected from moisture.

The industry produces standard incendiary tubes that have mechanical or grating ignition devices at the end, which facilitates the use of the fire method of explosion by insufficiently trained personnel (there is no need to make an incendiary tube, no skills are required in igniting the ignition tube with matches). In the picture above, a factory incendiary tube with mechanical igniter, with a grating igniter at the bottom. To ignite the ignition tube, it is enough to pull the pin on the mechanical igniter. and unscrew the head of the grater and pull it sharply

The following brands of standard igniter tubes are available:

ZTP-50. The igniter is mechanical or grating. Burning time 50 sec. (under water 40 sec.). The cord color is white.

ZTP-150. The igniter is mechanical or grating. Burning time 150 sec. (underwater 100 sec.). The cord color is white.

ZTP-300. The igniter is mechanical or grating. Burning time 360 ​​sec. (underwater 300 sec.). Cord color is blue.

If with the electric method of explosion the simultaneous detonation of several explosive charges does not cause difficulties due to the simultaneous supply of an electric pulse from the blasting machine to several electric detonators, then with the fire method of explosion it is impossible to achieve the simultaneous ignition of several incendiary tubes, and the difference in length will lead to non-simultaneous detonation of the charges. With the fire method of detonation, the problem of simultaneous detonation of several charges distant from each other is solved by transferring detonation from charge to charge using a detonating cord. Considering that the detonation transmission speed is more than 6 km. per second, the detonation of any number of explosive charges and at any distance from each other can be considered simultaneous

Related information.

The charge of the main explosive and the means of detonation are the main elements of the explosive device. Explosive means include initiation means and fuses.

Means of initiation can be divided into means of ignition, means of detonation and means of transmitting the fire and detonating impulse.

fuses, in addition to the initiation means, may include the following parts and mechanisms: target sensor (pressure, unloading, break, etc.), long-range cocking mechanism, self-destruction mechanism, non-removable mechanism or element, remote control mechanism, electric current sources. The fuse of an explosive device contains an algorithm for the operation of an explosive device, starting with its installation, transfer to a firing position, selection of targets (objects), ensuring non-removal, and, if necessary, self-destruction.

The following explosives can be used as the main charge of an explosive device: solid-state in the form of briquettes (for example, TNT blocks); powdered (for example, based on ammonium nitrate); granular (TNT in granules); liquid (for example, aquatol); plastic (plastic); gaseous (various oxygen-fuel or air-fuel mixtures).

By the method of obtaining the initial impulse (explosion) of the main explosive, acting on the means of initiation or directly on the charge of an explosive device, the following methods of detonation are distinguished:

• ? fire;
• ? electric;
• ? mechanical;
• ? chemical.

Their combinations can also be used, for example, electric fire, electromechanical, etc.

Fire method Explosion is based on the initiation of an explosive chemical reaction in the initiating explosive by exposure to a flame or a beam of sparks, for example, from a fire hole. To detonate secondary explosives by fire, it is necessary to have: a fire source (which can be a smoldering wick, matches or an electric incendiary cartridge, etc.); fire cord; detonator capsule. To trigger explosives based on propelling, initiating and various pyrotechnic compositions, a beam of fire or a bunch of sparks is sufficient, which can easily be obtained from a fire cord, a chain of match heads, etc.

Electric way Explosion is similar to fire, it is based on the detonation of the initiating explosive from the influence of a flame, but the ignition of the ignition composition is carried out using the high temperature of the filament of the electrical circuit. The principle of operation is simple: the current flowing through the incandescent “bridge” causes a flash of the igniting composition, which, in turn, already leads to the activation of the initiating explosive. To use the electric blasting method, electric detonators or electric igniters, current sources and wires are required. This method is used to produce an explosion at the required time or when it is necessary to simultaneously explode several charges. Explosion control (the so-called switching of the explosive electrical circuit) is carried out using an electrical conductor line, electromagnetic waves, as well as other methods that can control the closure of the explosive electrical circuit at a given point in time or the transfer of the fuse to the firing position.

Mechanical method detonation is based on the explosive detonation of the initiating explosive from an impact. For this purpose, a firing pin (striker) and a primer (detonator capsule) are used. The scheme for initiating a capsule composition is similar to the scheme for firing a shot from a firearm, when, under the influence of a spring, the firing pin pierces the capsule with its striker and ignites its composition, and the resulting flame force initiates the powder charge of the cartridge.

Chemical method Explosion is based on the initiation of an explosive process as a result of a rapidly or slowly flowing exothermic chemical reaction (a reaction that occurs with the release of heat) of reagents active to each other. This method is often used to switch an explosive circuit in order to transfer a charge from a safe to a combat position after a specified period of time or to self-destruct the charge after a specified time.

Combined method blasting is a combination of the above methods. For example, this includes electromechanical, electric fire methods, etc.

TO means of initiation These include devices designed to excite (initiate) the explosion of explosive charges, directly implementing one or another method of explosion.

Means of initiation are devices triggered by a simple initial impulse (impact, friction, puncture, heating, a sheaf of sparks, flame), designed to ignite gunpowder, pyrotechnic compositions and detonate high explosives.

Initiation means are divided into means:

• ? ignition;
• ? detonation;
• ? transmitting the initiating pulse 1.

Ignition media- initiation mechanisms that during their operation release thermal energy in the form of a ray of fire, heating of an incandescent filament, or spark discharge.

Rice. 4.2. Industrial electric igniters: (1) - wires; (2) - filament bridge; (3) - igniter composition; (4) - sleeve; (5) - plugs

These devices include: impact, pin, grating primers-igniters and electric igniters (Fig. 4.2) of industrial or homemade manufacture. The operating principle of electric

Fire igniters are as follows: an electric current passes through the filament, heating it, the pyrotechnic composition ignites and initiates the activation of the main ignition composition, which then forms a beam of fire.

Ignition means are used to detonate propellant explosives, initiating explosives and a number of pyrotechnic compositions. Electric igniters can work as an independent means of initiation, or as one of the elements of an electric detonator, electric capsule, squib, etc. When working at the site of an explosion, remnants of ignition agents can almost always be detected and can subsequently be the object of explosive identification examination.

Detonation means are initiation means used to initiate the detonation of secondary explosives.

These include blasting caps, fuses, and electric detonators. Detonation means usually have all the structural elements of an explosive device: an initiating explosive, triggered by a simple initial impulse in the detonation mode, a high explosive, a shell, so they can be considered as independent explosive devices. Figure 4.3 shows the design of detonator caps.

Exists two types of blasting caps:

• 1) beam, converting a thermal impulse (a ray of fire) into an explosive one;
• 2) impaling, converting a mechanical impulse in the form of a puncture, impact, friction into an explosive one.

In Figure 4.3. (a) schematically shows the structure of beam detonator capsules 1.

In practice, they are most often used beam blasting caps No. 8, which contain combined charges of initiating and high explosives and are used to initiate detonation of the explosive during blasting operations in the national economy. In military engineering, detonator caps KD-8A are mainly used. The detonator caps are mounted in a metal or paper sleeve, and the initiating explosive is additionally enclosed in a steel cup covered with a fabric mesh. Beam detonator caps are initiated by a beam of fire from a fire cord inserted into the cartridge case, which is the so-called incendiary tube used in the fire method of detonation. The detonator capsule can be detonated by a beam of fire from the igniter primer, electric igniter or detonating cord. In addition, an explosion of a detonator capsule can occur from various external influences, such as impact, heating of the housing, dismantling of the detonator, explosion of a nearby explosive charge, or a fall from a height of more than 1.5 m onto a concrete base.

Rice. 4.3. Design of detonator capsules:

• (a) - device of beam detonator capsules: (1) - sleeve;
• (2) - calyx; (3) - silk mesh; (4) - lead trinitroresorcinate;
• (5) - lead azide; (6) - tetryl; (7) - mercury fulminate; (b) - arrangement of electric detonators: (1) - safety shell; (2) - sleeve; (3) - cemented hexagen; (4) - calyx; (5) - lead azide;
• (6) - retarding composition; (7) - igniter composition;
• (8) - incendiary composition; (9) - filament bridge; (10) - frame; (11) - plastic plug; (12) - wires; (13) - tag 1 2

Electric detonators are used in the electrical blasting method.

Electric detonators They are detonator capsules with an electric igniter inserted into its sleeve, containing an incandescent bridge with an ignition head made of a heat-sensitive pyrotechnic substance (Fig. 4.3. (b)).

When an electric current is passed, the incandescent bridge of the electric igniter heats up, the pyrotechnic composition ignites and produces a beam of fire, which explodes the initiating composition in the metal cup, which leads to the detonation of the main charge of the detonator capsule. The explosion of the latter is the initiating detonation pulse in the main charge of the secondary explosive. When examining the site of an explosion from a detonator capsule, it is relatively easy to detect the remains of an incendiary tube, as well as electrical wires from an electric detonator.

Detonation means should also include intermediate detonators, consisting of a charge of a highly explosive explosive and designed for reliable transmission and amplification of the initial detonation pulse from the detonator capsule to the main explosive charge. Detonation means also include various fuses, consisting of a detonator capsule and an igniter capsule, which convert mechanical energy into an explosive detonation pulse. In addition, many fuses are capable of delaying the explosion time due to the combustion of the pyrotechnic composition of the moderator located between the igniter capsule and the detonator capsule; the most famous example is the fuse of UZRGM hand grenades, which has an explosion delay time of about 3.54 s. The design of a universal fuse for hand grenades is shown in Fig. 4.4.

Industrial detonation devices are commonly used to detonate improvised explosive devices, but homemade detonation devices are sometimes found that are extremely dangerous to handle due to a lack of knowledge about their design.

As means of initiating an explosion There may also be means of transmitting the initial explosive impulse, which include devices designed to transmit the initiating impulse in the form of a beam of fire (fire cord) or a detonation impulse (detonating cord). A fire cord can directly initiate propellant and initiating explosives, as well as various pyrotechnic compositions, and a detonating cord can also initiate medium-sensitive secondary explosives (dynamite, hexogen, etc.).

Rice. 4.4. UZRGM 1 grenade fuse:

• (1) - detonator capsule; (2) - moderator; (3) - connecting sleeve; (4) - safety pin; (5) - mainspring; (6) - impact mechanism tube;
• (7) - guide washer; (8) - drummer; (9) - striker washer; (10) - igniter primer; (11) - retarder bushing; (12) - release lever

To activate the explosive device, it has fuse, which, in addition to the initiation means, may include the following parts and mechanisms: target sensor (pressure, unloading, break, etc.); long-range cocking mechanism; self-destruction mechanism; anti-removal mechanism or element; remote control mechanism; source of electric current. The fuse of an explosive device contains an algorithm for the operation of an explosive device, starting with its installation, transferring to a combat position, selecting targets (objects), ensuring non-removability and, if necessary, ending with self-destruction. It is the fuse that forms and gives the command to detonate the warhead of the explosive device and, on the same command, initiates the explosion. The fuse can be built according to a simple scheme: an electric detonator, a current source and a switch (target sensor) or a detonator capsule and a firing pin with a trigger mechanism; or it can be a fairly complex device with electronic circuits.

Knowledge of the principles of operation of fuses and their technical implementation will allow employees of the Russian Ministry of Internal Affairs to successfully act when criminals use means of committing crimes that are particularly dangerous to public safety. Let's take a quick look basic mechanisms factory fuses and available data on the improvised fuses used.

Target sensor designed to record the moment in time of the impact of a target (object) on a selected area of ​​terrain, space or objects. The target sensor ensures that the explosive device operates as a standby munition, when it is triggered only as a result of a strictly defined target impact. The target sensor always provides for the selection of various influences. For example, in a number of mines, the target pressure sensor is designed for a load of at least 10 kg with an exposure time of at least 0.5 seconds. This, on the one hand, ensures a given level of noise immunity, and on the other, the orientation of the explosive device towards a specific type of target.

By operating principle Target sensors are divided into mechanical, electromechanical, electronic (including those that respond to changes in the magnetic or electric field, illumination, etc.) and chemical 2.

Depending on the a way to record the impact of a target sensors can record: the moment the target impacts certain items or objects (turning on electrical appliances, opening a door, moving an object, changing the position of an object, etc.); starting to move or stop the target; moving a target through a certain area of ​​terrain or premises; changes in pressure, degree of illumination, magnetic, electric, acoustic fields, etc.; other changes in the situation.

Pressure sensor purpose is designed for mechanical impact with a certain force and duration 3. Figure 4.5 shows the technical solutions of target sensors for an anti-personnel mine in a wooden PMD-b case and an improvised explosive device consisting of two metal plates made of tin with punched holes and protruding sharp edges, insulated with a thin dielectric film. When you press the spring-loaded cover of the PMD-6 mine, the safety pin is pulled out from the MUV-2 universal mine fuse (Fig. 4.5 (a)) and the floor-action detonator cap is activated. When stepping on the upper metal plate (Fig. 4.5 (b)), the sharp edges pierce the dielectric film and the electric detonator circuit is closed.

Rice. 4.5. VU with target pressure sensor 1:

• (a) - anti-personnel mine PMD-6: (1) - wooden mine cover;
• (2) - combat pin MUV-2; (b) - homemade target pressure sensor: (1) - metal sheets with sharp edges from holes;
• (2) - dielectric film; (3) - power supply of the explosive device;
• (4) - electric detonator; (5) - warhead of an explosive device

Unloading sensor designed to be activated when a load is removed from it. Figure 4.6 shows one of the typical diagrams of unloading sensors used in the designs of improvised explosive devices, and the MS-3 surprise mine.

Rice. 4.6. Explosive device with unloading target sensor:

(a) - homemade explosive device: (1) -

first electrode; (2) - second electrode; (3) - a piece of rubber; (4) -

power supply; (5) - electric detonator; (6) - warhead of an explosive device; (b) - industrial surprise mine

Tension sensor target is triggered when the target acts through a trip wire (thread, rope) stretched on a walking path, in a corridor, etc. When a person touches the tripwire, the pin is removed from the fuse trigger or the electrical contacts of the detonator are closed.

Break sensor The target is set in the same way as a tension one, with the only difference being that here the formation of a signal to detonate occurs when the tension wire breaks. A factory-made explosive device typically uses a thin electrical wire with special electronic circuitry as a target sensor. If the wire breaks, the electrical circuit of the detonator closes. Figure 4.7 schematically shows the designs of easy-to-manufacture homemade break target sensors used by militants of gang formations during hostilities in the North Caucasus in the 90s of the 20th century.

Rice. 4.7.

production 1:

• (1 and 20) - electrodes; (3) - stretching; (4) - power supply;
• (5) - electric detonator; (6) - warhead of an explosive device

Inertial sensor(position sensor) is activated by moving it in any direction or tilting it in any plane (depending on the design). Figure 4.8 shows a typical liquid mercury target sensor, which is often used in homemade booby traps. When a homemade mine-trap is tilted, the mercury ball moves inside the glass body of the fuse and, in a certain position, bridges the contacts of the detonator's electrical circuit.

Seismic target sensor registers the movement of people, equipment and animals by processing seismic signals in the ground. The sensor consists of geophones that respond to seismic ground vibrations, an analytical device that selects interference and false signals, and also determines the distance and direction of movement of the target. These sensors are widely used in factory-produced anti-personnel and anti-tank mines. For example, seismic sensors of modern anti-personnel mines make it possible to highlight the target (the movement of an infantryman in a given direction) against the background of a tank moving nearby.

Rice. 4.8. Explosive device with mercury position sensor 1:

(1) - mercury; (2) - electrodes; (3) - power supply; (4) - electric detonator; (5) - warhead of an explosive device

Magnetic target sensor reacts to the appearance near it of products containing metal with magnetic properties, for example, to the passage of an armored car or the passing of a metal detector sensor over it. These sensors are widely used in factory-produced anti-vehicle mines.

Optical sensor incorporates photo relays or LEDs that respond to changes in illumination in a wide range of electromagnetic radiation, including in the invisible zone of the spectrum. For example, an explosive device (or only a fuse) is placed in a case, when opened, light hits the LED, the detonator circuit is closed and the explosive device is detonated. In addition, sensors can be used that change the value of the photocurrent depending on the level of illumination of a particular object, and when the specified value of the current is reached, the fuse is triggered.

Temperature, barometric, wind, acoustic, electromagnetic and other sensors are quite rarely used for criminal purposes, and therefore are not considered here. However, it should be noted that determining the type and type of target sensor at the stage of inspecting the scene of an incident when an explosive device is detected will make it possible to protect the participants of the operational investigation team.

Using only target sensors in fuses does not allow in practice to create a sufficiently reliable and safe explosive device to handle, therefore industrial fuses (less often homemade) often contain additional mechanisms: long-range arming, deceleration, self-destruction, target counter.

Long-range cocking mechanism designed to place an explosive device in a firing position after some time has passed after the last command or human action. This is a kind of fuse against the miner's error, which makes it possible to move to a safe distance. The long-range cocking mechanism blocks the detonator actuator or the detonator itself for a certain time, preventing the last link in the chain of commands to detonate the detonator from operating.

As an illustrative example, let us consider the principle of operation of the long-range cocking mechanism of the MUV-2 universal mine fuse. Here, the long-range cocking mechanism is a plate (metal element) made of soft metal, most often lead, a loop of steel wire (cutter) spot welded to the rear of the firing pin, and a mainspring (Fig. 4.9).

Rice. 4.9. Mine universal fuze MUV-2 1:

(1) - MUV-2 assembled; (2) - body; (3) - rubber cap; (4) - metal element; (5) - bushing; (6) - T-shaped combat pin; (7) - striker with cutter; (8) - mainspring; (9) - safety pin

After the explosive device is installed on the tripwire, the upper safety pin is removed from the MUV-2 by the ring. Next, the firing pin, under the action of the mainspring, tends to move toward the primer, and the cutter begins to cut through the metal element. Depending on the temperature, this process lasts different times at room temperature - 15-20 minutes, in the cold - 40-60 minutes. After cutting the metal element, the firing pin will rest against the firing pin and the fuse will move into the firing position. If the combat pin is now removed, the explosive device will immediately detonate. If the metal element has not yet been completely cut through and at this moment the combat pin is pulled out, then the explosive device will not immediately detonate, since the firing pin will not be able to strike the primer. In homemade explosive devices, an electronic timer is sometimes used as a long-range arming mechanism, connected to the open circuit between the target sensor and the electric detonator. When a signal is received from the target sensor, the timer will begin counting down and after a specified period of time will close the electric detonator circuit to detonation. Thanks to this, if the target sensor is triggered by interference or there is an error when installing an explosive device, the perpetrator has time to disconnect the power from the detonator or leave the dangerous territory.

Deceleration mechanism used to turn on the target sensor at an estimated time (from fractions of a second to several months). An explosive device can be planted at the site several days or even months before the combat situation is released. For example, a magnetic sensor designed to be triggered when a door is opened will be included in the electrical circuit of the fuse after 12 hours, which means that only 12 hours after installation the explosive device will go into target standby mode, and before that time opening the door will not cause an explosion 1 .

Non-retrievable mechanism designed to detonate an explosive device when attempting to defuse it or remove it from an object. For this purpose, various devices included in the detonator circuit can be used. For example, an anti-personnel mine with a discharge fuse is placed under an anti-tank mine - a surprise mine. When an anti-tank mine is removed, a surprise mine is detonated.

Self-destruct mechanism designed to eliminate an explosive device (explosion or destruction without explosion of the main charge) after a specified time or when current sources are depleted.

Target counter gives a signal to detonate an explosive device after moving a specified number of targets near it. For example, when installing an explosive device to open a door, an explosion will occur after the tenth opening, which can lead to the death of law enforcement officers who arrived to inspect the scene and were not convinced of the safety of this action. The target counter is usually used in factory-made explosive devices with a proximity fuze.

Fuze control mechanisms (lines) are designed to change the state of an explosive device remotely at any time, regardless of the operating mode of the fuse. Control can be achieved by a radio channel, wired lines, mechanically, or an optical channel. Using these control lines, the explosive device can receive the following commands:

• ? transfer to a combat position, i.e. turning on the target sensor, starting the clock mechanism, etc.;
• ? carrying out an explosion immediately, despite the established operating algorithm (to prevent the removal of the explosive device in the event of a change in the operational situation);
• ? transfer to a safe position;
• ? neutralization without damage to the mining object (the explosive device or only the fuse is destroyed by a special squib without detonation of the main charge) 1.

Radio channel makes it possible to control an explosive device at a distance without carrying out preliminary work on laying and masking wires or special mechanical devices. As a radio channel in modern factory-made mines, special encoded receiving and transmitting systems are used, which have high security when transmitting commands in conditions of interference and false signals. In improvised explosive devices, amateur stations of any class are used with a command receiving distance of 10-20 m. To trigger fuses when using radio channels in improvised explosive devices, the following are often used: radio receivers tuned to a certain frequency; receiving devices for radio toys included in the electric detonator circuit; receiving parts for car alarms, etc. Radio fuses of simple designs are unreliable; they can react to radio interference and false signals, which can cause an unauthorized explosion, so it should be borne in mind that exposing such fuses to a strong noise signal from a Perseus-type radio jammer will most likely cause it to be triggered without permission.

Wired lines control lines usually reach tens and hundreds of meters in length. In recent years, optoelectronic control lines have been increasingly used; the influence of electrical noise (lightning discharges, stray ground currents, etc.) is negligible. The use of wire lines requires conditions, effort and time to lay and disguise them. After an explosion at the scene, they are easily detected 1.

Mechanical methods control of an explosive device includes a wide variety of devices and devices - from the cord, with the help of which the combat pin is removed, to the use of a sniper shot and the closing of the safety element with a bullet (Fig. 4.10). The latter option was often used by militants of gangs in the Chechen Republic.

Rice. 4.10. Mechanical method of controlling explosive device 2:

• (1) - electrodes; (2) - insulating film; (3) - fired bullet;
• (4) - power supply; (5) - electric detonator;
• (6) - warhead of an explosive device

As optical channels For control, laser and beam sources and receivers can be used, the operating principle of which is based on the receiver converting the control optical (infrared) signal into an electrical one and feeding it into the detonator circuit. In practice, there are known cases of using laser sights in improvised explosive devices.

As an example, consider the algorithm of action of the M-619 proximity fuse (USA). It is used to destroy moving equipment and includes in its design a seismic sensor (geophone), a source of infrared radiation and a signal processing and control unit. Its operating principle is as follows: the infrared source is located on one side of the road, and on the other side, an infrared radiation receiving device is installed, located next to the explosive device. Thus, the device operates in target waiting mode. The detonation occurs as follows. Ground vibration from the movement of a target approaching the charge is perceived by a geophone, which converts it into electrical signals transmitted to the control unit. The infrared receiver automatically starts working from the control unit and the explosive device is switched to the firing position. When the target crosses the infrared beam, the explosive device is triggered and the target is hit. In this case, a targeted explosive device is used (for example, the domestic MON 50 mine).

Homemade devices with such a complex mechanism of action are almost never found. Two types of homemade radio-controlled explosive devices are often used for criminal purposes. First - the simplest one, it uses a control unit and a radio-controlled toy receiver, which play the role of a radio fuse and radio transmitter. The disadvantages of this method of explosion are: short control distance; there is a constant danger of the fuse being triggered by some extraneous radio signal. It should be borne in mind that these explosive devices are extremely dangerous to handle and self-explosions often occur during their installation.

Second type Radio fuses use cellular communications. Here, a cell phone is used as a radio receiving device, the signal of which closes the microrelay contacts when calling. Through these contacts, electric current is supplied from portable batteries to the electric detonator. Recently, as a long-range cocking mechanism to protect against unauthorized operation of a cell phone when placing an explosive device in the firing position, an electronic timer is sequentially switched on between it and the actuator. The signal from the radio-controlled element starts the timer countdown, and the timer signal triggers the fuse. Sometimes, instead of an electronic timer, an electromechanical safety element (an electric motor with two contacts) is used. In this case, if, when installing an explosive device, the timer was triggered by a false signal (interference), then the criminal has time to break the detonator circuit or move to a safe distance 1 .