RU2291730C1 - Fire extinguishing method and device - Google Patents

Abstract

FIELD: fire prevention, containment or extinguishing specially adapted for particular objects or places, namely to extinguish oil, wood, natural gas fires, particularly with the use of granular carbon dioxide.

SUBSTANCE: method involves delivering granular carbon dioxide into combustion area along ballistic curve with the use of projectiles made as briquettes filled with granular carbon dioxide packed in porous elastic envelopes. Fire extinguishing device comprises projectile throwing means, which accelerates projectiles filled with fire-extinguishant in barrel under the action of gaseous working medium pressure applied to projectiles. Device also has gaseous working medium pressure creation means and bearing structure adapted to support above throwing means. The throwing means is made as self-loading air gun, which may perform continuous aimed firing to throw granular carbon dioxide briquettes to fire site.

EFFECT: increased efficiency.

9 cl, 2 dwg, 2 tbl

Description

The inventive method and device for extinguishing fire relate to extinguishing means of burning products of various nature and purpose, including oil, wood, natural gas and their derivatives, and more specifically to extinguishing means using granules of carbon dioxide.

Highly effective fire extinguishing methods based on the use of gaseous, liquid and solid carbon dioxide are known. During exposure to carbon dioxide, an oxidizing agent (air, etc.) is displaced from the fire zone. The minimum concentration of CO ₂ , stopping the combustion of various products, is from 13 to 16% (see the book by P.G. Demidov, "Fundamentals of Combustion of Substances", published by the Ministry of Public Utilities, Moscow, 1951). When using snow or granules of carbon dioxide, the combustion temperature decreases, because in the solid state, CO ₂ has a temperature of -78.2 ° C.

It should be noted that carbon dioxide does not participate in the formation of the greenhouse effect in the Earth’s atmosphere and can be used to extinguish various types of combustible substances, with the exception of the termite reaction of metal combustion.

In connection with the aforementioned, numerous inventions attempt to use solid carbon dioxide for fire fighting with varying degrees of efficiency.

The prior art methods of extinguishing burning liquids stored in tanks, "dry ice" by local injection of crushed carbon dioxide under a layer of burning liquid in compact portions. The diameter of the shot is 3-4 cm (SU No. 1687266, A 62 C 3/06).

According to SU No. 776616, A 62 C 1/10, carbon dioxide is supplied to the burning surface of the liquid in the form of porous spherical granules, which, intensively evaporating, freely move along the surface of the liquid due to the reactive forces of the outgoing gases. In this case, intense heat exchange occurs between carbon dioxide and a heated or homeothermic layer of liquid, as a result of which the surface layer is cooled to a temperature lower than the flash point, after which combustion ceases.

The effectiveness of the known methods is low, because Solid carbon dioxide is supplied to the surface area in a confined space. The adhesion of the granules, as well as their crushing into smaller parts, makes it difficult to feed the granules into the combustion zone and their distribution in the burning space.

The closest analogue (prototype) of the proposed method is the solution disclosed in US No. 6442968, F 25 J 1/00.

According to a known solution, fire extinguishing is also carried out with solid carbon dioxide, which before use is obtained in the form of granules by spraying liquid carbon dioxide in a massive fire extinguisher specially designed for this purpose. Finished granules are fed into the combustion zone by a rotor, which is part of the same fire extinguisher.

The disadvantages of this known solution are primarily due to the inextricable connection of the process of feeding the granules with the stage of their manufacture, which complicates the supply of granules to the fire zone, reduces the efficiency of fire extinguishing, and also increases its cost. Moreover, the device used does not have mobility and autonomy, but depends entirely on energy sources and raw materials (liquid carbon monoxide). The consequence of this is the complication of the supply of the reagent to the fire zone, the increase in the cost of extinguishing units and the complication of the operational movement of the device.

It should also be noted that the rotor or Laval nozzle used to implement the known method, emit granules at different speeds, because in a two-phase medium, the speed of the granules obeys the law of normal distribution, and is also characterized by a high energy consumption for throwing granules, because The efficiency of a two-phase throwing mechanical device is extremely low.

The prior art method for extinguishing fires using small arms or artillery weapons to deliver an extinguishing agent, an inert gas. The last to fill the tank, the shape of which is similar to a projectile with the caliber of the corresponding small or artillery weapons, while the inert gas is placed in the cavity of the shells intended for explosives, equipped with a fusible insert (RU 2014857, A 52 C 19/00). Under stationary conditions, the gas is held by plugs from a material whose melting point is lower than the temperature in the ignition zone. When the container enters the zone of the highest intensity of ignition, the plugs melt, the inert gas is released from the vessel and stops burning.

It should be noted that despite the fact that when implementing the known solution, the extinguishing agent is delivered over considerable distances, the efficiency of the method is not high enough, which is associated primarily with the physicochemical characteristics of the inert gas. The use of metal shells significantly increases the cost of the fire extinguishing process, and also poses a real threat to people's lives.

According to the solution disclosed in patent RU 2053821, A 62 C 17/00, shells with a fire extinguishing agent placed in an elastic shell are fired at fire using a hinged method.

The gun, according to the known solution, contains a means of throwing shells with a fire extinguishing element by dispersing shells in the barrel by applying pressure to a shell of a gaseous working medium, a system for generating said pressure and a support on which said throwing means is mounted. In the known device for creating gas pressure on a projectile in an accelerating barrel, a storage chamber with an energy source and an ignition device are provided, between the storage chamber and the barrel there is a shut-off device (receiver), while the shut-off device contains a non-return shut-off valve with automatic blocking, and at the exit section openings of the booster trunk mounted sliding notch knives mounted radially relative to the longitudinal axis of the booster barrel.

As a source of energy in a known solution uses a combustible gas, such as propane. A mixture of propane with air is ignited by an electric candle from an electric source and creates a pressure that allows the projectile to disperse at a given speed. Knives incise the elastic shell when the projectile leaves the boom. In flight, the oncoming air stream tears (tears) the shell of the projectile, and the fire extinguishing composition enters the fire in the form of atomized powder or aerosol. According to experts, it takes about 30 minutes to recharge a known device, which significantly reduces the effectiveness of fire fighting.

It should also be noted that, despite a significant number of common essential features of the claimed device and the known device, the latter cannot be used to extinguish a fire with carbon dioxide granules (ignition of the working fluid excludes the possibility of using carbon dioxide granules).

The closest to the claimed integrated solution are a method of extinguishing fire with shells containing granules of carbon dioxide, directed along a ballistic curve, and a device for implementing this method, disclosed in US No. 5507350, A 62 C 3/02, publ. 04/16/1996

According to the prototype solution, in order to extinguish the fire, in particular, they use an artillery gun in the form of a self-loading air gun. Capsules containing granules of carbon dioxide are fired from a cannon. Capsules are enclosed in a strong, airtight shell. The gun contains a means of throwing shells containing granules of carbon dioxide, by dispersing the said shells in the barrel by pressure on the projectile of a gaseous working fluid, a system for generating said pressure and a support on which the gun is mounted.

The use of shells in a sealed shell prevents the creation of a moving curtain of fire in the form of a cloud of carbon dioxide during the fire fighting process, and the gun requires frequent reloading, which also reduces the effectiveness of fire fighting.

The objective of the proposed integrated technical solution, including two objects - a method and device for its implementation - is to increase the efficiency of fire extinguishing using granules of carbon dioxide.

The problem is solved by the following.

1. During fire extinguishing, carbon dioxide granules are introduced into the combustion zone according to the ballistic curve by shells made in the form of briquettes with carbon dioxide granules placed in porous elastic shells.

2. A device for extinguishing fire, used to implement the method and associated with it by a single inventive concept, comprising means for throwing shells with a fire extinguishing element by dispersing shells in the barrel by applying pressure to a shell of a gaseous working fluid, a system for generating said pressure and a support on which said means are mounted throwing, contains:

- a means of throwing shells in the form of a self-loading air gun, made with the possibility of operation in the mode of continuous aimed firing of shells in the form of briquettes with carbon dioxide granules placed in porous elastic shells. Implementation of the creative intent of the authors is possible with the following parts and mechanisms in the device:

1) a container for placing a shell tape with said briquettes,

2) a mechanism for supplying said briquettes in a projectile belt to a gun, configured to detach shells,

3) a mechanism for automatic reloading of shells kinematically associated with the feed mechanism of these briquettes,

4) a pneumatic system for creating a pressure of a gaseous working fluid, which is used as carbon dioxide or nitrogen or an inert gas, on a projectile-briquette,

5) a carriage on which the projectile is mounted.

The inventive device is illustrated in the graphic material presented in figure 1 and figure 2. Figure 1 is a schematic illustration of one of the embodiments of the inventive device in working condition, Figure 2 is a schematic illustration of the mechanism for supplying briquettes in a projectile belt into a gun.

A self-loading air gun is mounted on carriage 1. The carriage is designed to give the barrel 2 guns the necessary position before firing (using the aiming mechanism, not shown in the drawing), for absorbing (recoil devices, not shown in the drawing) part of the recoil energy during firing, as well as gun movement. Carriage 1 can be mobile - on a wheeled or tracked track, as well as semi-stationary - on a moving base. Barrel 2 with chamber 3 (projectile space) is designed to accelerate projectile 4 to the required speed and provide the desired direction of its flight. The storage chamber 5 is designed to accumulate a fixed volume of compressed gas of constant pressure and, accordingly, to obtain a constant initial velocity of the projectiles 4 with each shot. The storage chamber 5 is connected by a channel 6 to the chamber 3 of the barrel 2. The shut-off valve 7 of the chamber 5 is quick-acting and installed in the channel 6. The valve 7 is closed by means of springs 8, and it is opened by the opening drive 9, which interacts with the front copier 10 mounted on sliding bolt 11.

The device is equipped with a receiver 12, designed to smooth out pressure fluctuations in the gun’s pneumatic system, made in the form of a cylinder with compressed carbon dioxide or nitrogen, or other inert gas, the inlet of which is equipped with a control valve 13. The receiver 12 is connected to a high pressure cylinder 14 with carbon dioxide or nitrogen, or other inert gas, which is the source of energy for the operation of all gun mechanisms. The receiver 12 provides a working gas pressure of ~ 6 atm or more.

In the container 15 is placed the projectile tape 16 (made of porous elastic material, for example, polyethylene or propylene, projectiles 4 made of compressed carbon dioxide granules are included in the tape at equal distances from each other). The container 15 is mounted on the carriage 1 and is connected by a flexible sleeve 17 with the neck 18 of the feed mechanism 19 of the tape 16, providing movement of the projectile tape 16 from the container 15. A longitudinally sliding shutter 11 is designed to direct the projectile 4 into the chamber 3 and mechanically lock the barrel 2. In at the end of the stroke, the shutter 11 mechanically turns on the actuator for opening the shut-off valve 7. The longitudinally-sliding shutter 11 is driven by a bilateral pneumatic cylinder 20. At the end of the stroke, the longitudinally-sliding shutter 11 also includes a check valve a different stroke 21, and in the extreme rearward position a working valve 22. A separator (knife) 23 is fixed to the front end of the shutter 11. The feed mechanism 19 of the projectile tape 16 consists of an inlet neck 18 and a wide sprocket 24 rotating on axis 25.

On the longitudinally sliding shutter 11, a driving element 26 is fixed, which, interacting with the rotating copier 27, during the working stroke of the shutter 11 turns the sprocket 24 by one step, feeding the next projectile 4 to the axis of the barrel 2.

The carriage 1 contains a base 28, a rotating part 29 and a swinging part 30. The base 28 can be mounted on the ground or rigidly mounted on a fire fighting vehicle.

On the rotating part 29 of the base 28, the swinging part 30 is mounted on the pins 31, the pneumatic equipment of the cylinder 14 and the receiver 12 are installed, auxiliary equipment - valves, manometers, etc. - not shown in the drawings. The swinging part 30 is the self-loading air gun itself, on which the arms 32 for guiding the barrel 2 horizontally and vertically are fixed. On the handles 32, a manual valve 33 for supplying gas from the receiver 12 to the storage chamber 5 and a trigger 34 for activating the valve of the stroke 22 of the longitudinally sliding shutter 11 is installed.

The projectile separator 23 is mounted on a longitudinally sliding shutter 11 with the possibility of interaction with the profile surface of the sprocket 24. The pneumatic cylinder 20 is connected by pipelines 35 to a high-pressure cylinder 14 and a receiver 12.

A fire extinguishing device can be equipped not only with a carbon dioxide projectile launcher, but also with additional devices: a thermostatically controlled container for storing containers with projectile belts, devices for loading containers onto a carriage, storage of spare cylinders of compressed gas, etc. It is advisable to provide locations for a fire crew, serving a self-loading airgun.

The claimed device operates as follows.

Before turning on the system, check the completeness of the installation, the presence of a gas cylinder, a container with the necessary number of shell tapes and their condition, check the pressure in the cylinder and receiver, and check the free movement of the barrel. Without loading the cannon with tape, the shutter and the feed sprockets are pre-checked with a few clicks of the trigger.

The gun must make a few blank pops without subsequent etching of the gas.

Actually, work begins with the installation of the projectile tape 16 in the sprocket 24 of the feed mechanism 19 with the first projectile 4, namely in the penultimate socket of the sprocket 24, turn on the manual valve 33 and press the trigger 34, under the action of which the valve of the stroke 22 of the double-sided pneumatic cylinder 20 is opened the shutter 11. The shutter 11 is moved forward by the driving member 26 through the rotating copier 27, which rotates the sprocket 24, moving the projectile 4 to the channel line of the barrel 2. With further movement of the shutter 11, sleep is separated row 4 with a knife 23 from the tape 16, and the shutter 11 sends the projectile 4 to the barrel 2. At the same time, the bore 2 is locked by the projectile 4. At the end of the stroke, the shutter 11 with the front copier 10 presses the opening actuator 9 of the shut-off valve 7, the gas instantly fills the chamber 3 through channel 6, the projectile 4 accelerates. On the 0.3 m acceleration path, projectile 4 weighing 1 kg acquires a speed of ~ 25 m / s.

At the same time, the back-up valve 21 of the shutter 11 is turned on. The shutter 11 starts to move backward, the shut-off valve 7 closes and the storage chamber 5 begins to fill with compressed gas from the receiver 12 with the adjustment of the valve 13. The receiver 12 is replenished with gas from the cylinder 14. The shutter 11 returns to its original position, while the rotating copier 27 prepares the sprocket 24 for the next turn. When the shutter 11 is returned to its extreme rear position, the stroke valve 21 is turned on. The cycle of operation is repeated until the trigger 34 is released, while the stroke valve 21 closes.

After the shell tape 16 has been used up, a new container is installed in place of the empty container 15, and the new tape 16 is threaded through the flexible sleeve 17 into the feeding mechanism 19. The manual valve 33 is closed.

The efficiency of the barrel reaches a value of 0.3. Briquettes are continuously fed by the feed mechanism into the barrel, into which gas is supplied from the compressed gas cylinder through the receiver with a pressure of 6 atm through the control valve to the barrel, the briquette in the barrel is accelerated by compressed (~ 2 atm) gas and is shot along the ballistic curve into the fire zone. Regulation of accuracy and range is subject to the known laws of ballistics.

Throwing briquetted solid carbon dioxide with a barrel air gun with an automatic reloading device allows for the massive supply of briquettes to the fire. Calculations show that when the briquette mass is m = 1 kg and the throwing speed is V = 25 m / s, the energy E spent on throwing the briquette will be equal to:

.

.

With a trunk diameter of 100 mm and a cross section (S) of ~ 80 cm ² under conditions of a maximum barrel pressure of ≅6 atm and an average barrel pressure of ΔP _cf ≅2 atm, the force on the briquette P _sv will be:

P _sv = ΔP _sv · S = 2 · 80 = 160 kg · s = 1600 N.

With these parameters, the optimal barrel length l _trunk is determined from the ratio:

E - energy expended, Nm;

R _St. - the force on the briquette, N.

The maximum ballistic throwing distance of the briquette L when the barrel is tilted at an angle α = 45 ° to the horizon without taking into account air resistance is significant and will be:

V = 25 m / s - throwing speed.

At the indicated low level of gas pressure during throwing, the gun can be made thin-walled, which makes it easy and convenient for firing at a large area of fire, while the throwing device can be located at a considerable distance from the heat affected zone of the fire.

From the above it follows that in a similar way ballistics and parameters of a gun having a larger diameter and allowing the use of briquettes weighing more than 1 kg can be calculated.

During the study of a computer model and an experimental study of the sublimation of granules (briquettes) of carbon dioxide at different combustion temperatures of wood, oil, natural gas, the authors obtained the data presented in table 1.

Table 1 Products Temperature in the combustion zone, ° С The evaporation time from the briquette of carbon dioxide layer thickness 1 mm Wood 1000 0.15 s Oil and gas fountain 1100 0.13 s Petroleum products, oil 1300 0.12 s Methane 1950 0.08 s

The estimated flight range of the briquette (diameter 100 mm) of carbon dioxide in the fire zone until it completely evaporates at a speed of V = 25 m / s will be the value indicated in Table 2

table 2 Temperature in the combustion zone, ° С The range of the briquette of carbon dioxide in the fire zone, m 1000 187.5 1200 162.5 1300 150.0 1950 100.0

Consequently, with a design ballistic throwing range of 60 m, the briquettes create a carbon dioxide cloud throughout the flight depth and still retain 68%, 63%, 60% and 40% of their volume in the incidence zone in the fire at different fire temperatures, thereby creating carbon dioxide the curtain at the point of contact of carbon dioxide briquettes.

Thus, it is possible to increase the efficiency of fire extinguishing not only by delivering a fire extinguishing agent over a long distance and affecting a wide area of fire, but also by maintaining the integrity of carbon dioxide briquettes along the entire throwing path in the fire zone.

The use of a polymer elastic porous shell for transporting compacted dry ice granules during ballistic throwing provides the following advantages:

- the free exit of gaseous carbon dioxide through the porous polymer shell due to their partial evaporation in the transport polymer tape before firing. Due to this, the shell size is maintained without bloating, which would certainly have occurred when using a continuous non-porous shell. The swelling of the shell prevents the charging of the barrel due to dimensional incompatibility;

- the best mate in terms of barrel size, i.e. obturation (tight fit) of the missile body with the bore, due to the preservation of the elasticity of the shell of the briquettes, which are enclosed by granules of carbon dioxide;

- achieving a dense obturation of the missile body with the barrel channel along its entire length allows more efficient use of the working pressure in the barrel, increase the efficiency of ballistic throwing and thereby increase the throwing range or, accordingly, reduce the consumption of compressed gas (i.e., reduce the cost of expenses).

The results allow us to conclude that the benefits of ballistic supply of briquetted carbon dioxide to the combustion zone, while it is possible to regulate the supply of briquetted carbon dioxide by controlling the rate of fire from single pneumatic shots to automatic bursts, determined by the duration and rate of possible capacity of the container and the technical perfection of the briquettes feeding mechanism trunk. There cannot be a heating device for a high rate of fire, because briquettes have a high cold storage capacity, so the device should have only thermal insulation from the cold for safety and ease of maintenance.

One of the characteristics that determine the effectiveness of fire fighting is the amount of carbon dioxide required to stop burning in air, i.e. 16% (which follows from the data given in the book of L.G. Demidov, the link to which is given above).

The achievement of this concentration (16%) in 1 m ^{3 of} volume is carried out by evaporation of 0.2 kg of briquette from carbon dioxide, i.e. a briquette of 1 kg provides a ceasefire in a volume of 5 m ³ . For the best aerosol fire extinguishers, this indicator is 2 times lower.

The proposed method and device for extinguishing fire at a rate of 10-20 rounds per minute allows for 1 minute to reach a ceasefire in a volume of 100 m ³ , i.e. in the amount of one average apartment. At the same time, carbon dioxide briquettes can be targeted to a height of a 20-story building.

The main advantages of extinguishing fires by the claimed solution are as follows:

- ballistic throwing of the refrigerant into the fire zone is characterized by high energy efficiency (0.3), which allows to minimize the fire extinguishing device in terms of mass and size parameters;

- created conditions for the use of discrete briquettes of carbon dioxide in the form of a continuous "stream" - a line of flying briquettes when firing bursts;

- more effective extinguishing, exceeding the existing water-jet, foam and aerosol extinguishing means not only in volumetric fire suppression, but also in the distance of remote blocking of the spread of fire;

- ensuring the prevention and suppression of gas and oil and gas fires by dynamically breaking a burning jet, supercooling solid carbon dioxide in oil and gas storages, tanks, cylinders, etc .;

- mobility of using briquettes and throwing guns without the need for their long-term storage and special costs for stationary equipment;

- provision of extinguishing of switched on, under current burning electrical equipment and power plants at voltage up to 10 thousand volts;

- providing remote control fire extinguishing with the location of the barrel devices on the turrets or mounts, which can be robotic;

- reducing the cost of preparing carbon dioxide briquettes, using their centralized manufacture at cluster (zone) units serving fire hazardous areas of human activity;

- reducing costs and the complexity of the fire extinguishing process in general;

- environmental safety when using carbon dioxide.

It is optimal to produce carbon dioxide briquettes by well-known industrial methods, the connection of briquettes into a chain is easily feasible on the basis of the production of sausages, wieners, for example, on packaging and packaging equipment sold by Intermash LLC (Internet address http://www.rau.su/expo /Katal_99/9_133_1.NTM), in particular on automatic machines for filling and packing bulk products in bulk or semi-automatic packages with a weight or volumetric dispenser, as well as semi-automatic machines for filling and packing bulk products in bulk plastic or plastic packages with weight, volume or electronic dispenser. You can use equipment known from publications, for example from RU z.95110474, A 62 C 11/00, etc.

Transportation to places of ignition in thermostatically controlled containers can be anticipated or directly.

Presented in the application, examples of implementation of the invention do not exclude the existence of other implementation options that do not change the essence of the solution.

Claims (9)

1. The method of extinguishing fire by introducing into the combustion zone of shells with granules of carbon dioxide, directed along a ballistic curve, characterized in that the shells are made in the form of briquettes placed in porous elastic shells. 2. A device for extinguishing a fire, including a self-loading pneumatic gun for throwing shells with granules of carbon dioxide by dispersing these shells in the barrel by applying pressure to a shell of a gaseous working fluid, a system for creating the specified pressure and the support on which the gun is mounted, while the shells are made in the form of briquettes placed in porous elastic shells. 3. The fire extinguishing device according to claim 2, characterized in that it comprises a container for placing a projectile belt with said briquettes and a mechanism for automatically reloading shells with a means for supplying said briquettes to said gun configured to separate shells, a gaseous working pressure generating system body on the projectile is made pneumatic using carbon dioxide, or nitrogen, or inert gas as a working fluid, and the support is made in the form of a gun carriage. 4. The fire extinguishing device according to claim 3, characterized in that the pressure generating system comprises a high-pressure cylinder with carbon dioxide, or nitrogen, or an inert gas, a storage chamber communicating with the specified cylinder through the receiver, and with the barrel chamber through the channel , in which a shut-off valve is installed, configured to open and close said chamber. 5. The device for extinguishing fire according to claim 4, characterized in that the shut-off valve is equipped with a spring that provides closing of the specified channel, and an opening drive interacting with the front copier mounted on a longitudinally sliding shutter. 6. The device for extinguishing fire according to claim 3, characterized in that the mechanism for automatic reloading of shells contains a longitudinally sliding shutter with an actuator in the form of a two-sided pneumatic cylinder interacting with the driving element of the copier, made with the possibility of rotation and interaction with the feed mechanism of briquettes in the projectile tape in a gun, while the indicated pneumatic cylinder is connected by pipelines to a high-pressure cylinder and a receiver. 7. The fire extinguishing device according to claim 6, characterized in that the briquette feed mechanism in the projectile tape comprises a wide sprocket with a neck, wherein said sprocket is kinematically connected with a longitudinally sliding shutter provided with a spacer element. 8. The fire extinguishing device according to claim 7, characterized in that the dividing element is made in the form of a knife. 9. Fire extinguishing device according to any one of claims 3 to 8, characterized in that the carriage is made with two degrees of freedom.

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