RU2545850C1 - Generator of fire extinguishing aerosol - Google Patents

Abstract

FIELD: fire safety.

SUBSTANCE: generator of fire-extinguishing aerosol comprises a housing made of two oppositely fastened cup-shaped semi-housings to form a gap between their collars, providing the opportunity of discharge of the aerosol mixture, a start assembly is mounted in the gap, in each semi-housing a pyrotechnic charge is placed, mounted on the walls of the corresponding semi-housing by the bearing heat-insulating layer to form a free volume between the end surfaces of the charges. According to the invention, the gap between the collars is made in the form of uniformly placed radial tubular nozzles with the diameter of 5 to 8 mm, with the ratio of the total area of burning of the end surfaces of the charges to the total cross-sectional area of the tubular nozzles - within the range of 65-90, at that between the nozzles the snug fit of the collars to each other is provided by means of fastening elements.

EFFECT: in use of the proposed device the fire-extinguishing efficiency is provided, the zonal temperature of the aerosol jet is reduced at a distance of more than 0,3 m from the outlet of the generator.

8 cl, 2 tbl, 2 dwg

Description

The invention relates to fire fighting equipment, in particular to devices generating an aerosol mixture of combustion inhibitors, and is intended for volumetric extinguishing of a fire when throwing it into a fire source or during stationary installation in closed volumes.

Fire extinguishing aerosol (GOA) generators are known from the state of the art in the field, both being thrown into the source of fire (operational use) and permanently installed in a protected volume, for example, RF patents Nos. 2403930, 2256474, 2237503 and others.

Some of the well-known GOAs can functionally be either castable or stationary.

The well-known "Fire-extinguishing aerosol generator" (RF patent No. 34383, class A62C 3/00, publ. 2003), containing a housing composed of two counter-mounted dish-shaped containers with a gap between their flanges, forming an outlet nozzle, where the foam is placed gasket, pyrotechnic charges, fixed in both containers of the body through a heat-protective layer of gypsum, an initiation unit made in the form of a resistor filled with adhesive igniter and mounted axially symmetrically between the pyrotechnic joints with flanges mounted flush with the ends of the heat-protective layers, and the adhesive igniter is made mainly of a mixture of epoxy resin and potassium nitrate in a mass ratio of 2: 3.

The reasons that impede the use of the known device include insufficient extinguishing efficiency (45 g / m ³ ), high temperature of the aerosol jet at distances greater than 0.3 m from the outlet of the generator, as well as the use of building gypsum as a heat-shielding material for the casing.

Before installing the charge, a solution of gypsum in water is poured into the body of the product. Then a charge is pressed into the semi-liquid gypsum. Water from the uncured solution can be absorbed into the charge of the aerosol forming composition and wash the chemical components out of it. As a result, the product may either lose its fire extinguishing effectiveness or may not start at all. Therefore, it is necessary to introduce some kind of protection of the charge of the aerosol-forming composition from moisture, which complicates the manufacturing technology and increases the consumer cost. In addition, with temperature changes, due to the rigidity of the gypsum after it is cured, there is a danger of a gap between the gypsum and the charge and flame penetrating into this gap, which can lead to a sharp increase in pressure in the product and rupture of its body. Thus, the use of an aqueous solution of gypsum reduces the reliability of the product.

Over time, gypsum loses its strength, becomes brittle. When the product is exposed to strong shock or vibration loads, as well as temperature changes in the gypsum, cracks or chips form, the charge reservation on the side surface is violated, which also leads to abnormal operation of the product.

Known "Throwing fire extinguishing device" (RF patent No. 2164809, class A62C 19/00, publ. 2001), including a housing made of two counter-fastened dish-shaped containers with a gap between their flanges, forming an annular output nozzle, coaxial to which an ignition unit is mounted under the bracket-handle, the pyrotechnic charge is made of two parts, each of which is fixed in a carrier heat-insulating layer in a plate-shaped container, while the free end of the charge is located below the flanging, and the bearing heat-insulating osloyki made of plaster.

The reasons that impede the use of the known device include insufficient extinguishing efficiency (45 g / m ³ ), high temperature of the aerosol jet at distances of 0.7 m and further from the outlet of the generator, as well as the use of gypsum.

In terms of the set of essential features and the technical result achieved, the closest technical solution to the claimed one is the invention according to patent No. 2164809, which is chosen as a prototype.

The problem to which the invention is directed, is the development of GOA, providing higher fire extinguishing efficiency while lowering the zonal temperature of the aerosol jet.

When using the proposed device provides the following technical result:

- fire extinguishing efficiency of the generator is a value not exceeding 28 g / m ³ due to the formation of evenly spaced radial tubular nozzles between the flanges and a certain ratio (K) between the total combustion area of the charge surfaces and the total cross-sectional area of the tubular nozzles;

- the reduction of the zonal temperature of the aerosol jet at a distance of more than 0.3 m from the outlet of the generator (radial tubular nozzle) is ensured by a certain diameter of the nozzle openings and the simultaneous use of the entire set of features;

- additional reliability in the operation of the generator due to the combination of design features and the use of an elastic compound instead of gypsum.

The achievement of the indicated technical result is ensured by the fact that the fire extinguishing aerosol generator, comprising a housing made of two counter-mounted cup-shaped half-shells with a gap between the flanges, allowing the aerosol mixture to escape, has a launch unit in the gap, a pyrotechnic charge is placed in each half-shell, fixed on the walls of the corresponding half-shell by means of a supporting heat-insulating layer with the formation of a free volume between the end faces charge surfaces, characterized in that the gap between the flanges is formed in the form of uniformly spaced radial tubular nozzles with a diameter of 5 to 8 mm, with a ratio of the total combustion area of the end surfaces of the charges to the total cross-sectional area of the tubular nozzles within 65-90, and between the nozzles provide tight fit flanges to each other through fasteners.

For ease of use, the generator can be additionally equipped with a bracket-handle (refillable version) or a bracket (stationary version).

The most convenient and safe throw-in generator will be when the bracket-handle is installed in the location of the launch unit, which can be used as a manual start device of a grater or impact type.

For the stationary version, it is optimal to make the bracket in the form of a trapezoid with the possibility of fastening it with a small base of the trapezoid to the plane of the half-housing, and it is preferable to use an electric starter as the launch unit.

The use of a compound based on two-component silicone rubber with a filler as an insulating layer provides additional reliability of the generator, since water is not used in the assembly process, the elastic compound provides a solid connection with a pyrotechnic charge, does not crack under vibration loads or during long-term storage, and the filler on based on calcium and / or magnesium carbonates only contributes to maintaining structural integrity and complementary to the cooling of the combustion products.

The essence of the invention is illustrated in the drawing.

In Fig.1 shows a generator of fire extinguishing aerosol (GOA) in the context, and in Fig.2 is a top view.

GOA includes: a housing (1) made of two half-shells (1) of a cup-shaped shape, counterclosed to each other through flanges (2). A gap (3) is formed between the flanges (2), in the form of radial tubular nozzles that allow the aerosol mixture to escape, a launch unit (4) is installed in one of the radial nozzles (3), a pyrotechnic charge is placed in each half-housing (1) (5) mounted on the walls of the half-shell (1) by means of a supporting heat-insulating layer (6) with the formation of a free volume (7) between the end surfaces of the charges (5). In this case, the radially located tubular nozzles (3) are made with a diameter of 5 to 8 mm, and the ratio of the total combustion area of the end surfaces of the charges (5) to the total cross-sectional area of the tubular nozzles (3) is observed within 65-90. The half-bodies (1) are rigidly interconnected by flanges (2) by means of fasteners (8) with tight contact of the flanges surfaces (2) in the spaces between the nozzles (3).

Operational generators are supplied with a handle-handle (9) installed near the launch unit (4). As a start unit (4), a manual start device of a grater or impact type is used. For the stationary version, instead of the bracket-handle, a bracket (not shown) in the form of a trapezoid is installed on the GOA, and an electric starter is used as the launch unit.

As a supporting heat-insulating layer (6), a compound based on two-component silicone rubber with a filler based on calcium and / or magnesium carbonates was used.

The proposed GOA during its operational use works as follows:

The handle-bracket (9) on the body (1) is used to carry the generator and to cast it into the protected room. When a fire is eliminated, the GOA operator (fireman) must manually activate the start-up unit (4), throw the generator inside the protected room through a door, window, or other opening, which must then be closed.

The manual start device, which is used as a start unit (4), has a delay means for initiating pyrotechnic charges (5) with the duration necessary to perform GOA refueling into the protected room. After the delay, the heat pulse from the start-up unit (4) ignites the pyrotechnic charges (3), which begin to burn stably and evenly at the ends. The aerosol generated during the combustion of pyrotechnic charges (5) with high intensity leaves radial tubular nozzles (3) located uniformly around the circumference of the generator, which leads to efficient filling of the protected area with aerosol, ensuring reliable elimination of the fire sources.

The use of a compound based on two-component silicone rubber with a filler based on calcium and / or magnesium carbonates as a heat-insulating layer (6) provides the following advantages compared to building gypsum used in analogues:

- During the polymerization of two-component silicone rubber, water is not used and no water is released that can wash any chemical components out of the pyrotechnic charge (5).

- After polymerization of two-component silicone rubber with a filler, the heat-insulating layer (6) has elasticity, the pyrotechnic charge (5) is very well protected from shock and vibration.

- Provides a reliable reservation of the side surface of the pyrotechnic charge (5).

- Provides effective thermal protection of the housing wall (1) during operation of the product.

Good adhesion of the heat-insulating layer (6) to both the pyrotechnic charge (3) and the metal wall of the housing (1) allows the pyrotechnic charge (3) to be very securely fixed inside the generator, which is the most important factor for GOA operational use.

In the work of the proposed GOA with its stationary use there will be the following changes:

Instead of the bracket-handle (9), a bracket is used (not shown in the drawing), with which the generator is attached to the walls, ceiling or other surfaces inside the protected room. Also, as an ignition unit (4), an electric starter is used.

In the configuration for stationary use, the proposed GOA acts as the executive body of the automatic fire extinguishing system and is activated when an electrical signal is supplied from the control system to the launch unit (4).

In all tests, the silicon-organic two-component compound “Vixint PK-68” grade A: TU 38.103508-81 mixed with marble chips in an approximate ratio of 1: 3 was used as a heat-insulating layer, marble chips were used mainly with a particle size of no more than 1.5 mm

The manufacture of GOA is the following process. Half-shells (1) with flanging (2) of which the housing (1) consists are made by stamping. On the flanging (2) of each half-body, recesses are uniformly formed in an amount equal to the number of nozzle holes (3) plus one recess for installing the sleeve under the launch unit (4). The notches in the flanges (2), which, after assembling the GOA, form tubular nozzles (3), are also stamped. Either a bracket-handle (9) is welded to one of the half-bodies (1) (when using GOA as an operational one), or studs for attaching the bracket (for stationary execution). Each of the half-shells (1) contains a pyrotechnic charge (5). In a separate container, the necessary amount of vixinta with marble chips is mixed. The resulting mixture is poured into the gap between the inner surface of the half-shells (1) and the pyrotechnic charge (5) to the upper end of the charge. After polymerization, this mixture is a heat-insulating layer (6), and it also fixes the charge (5) inside the cup-shaped half-shell (1). Between the half-shells (1), a sleeve is installed for screwing in the launch unit (4). The filled half-shells (1) of a cup-shaped form are connected by flanges (2) with recesses, the combination of which forms nozzle openings (3). The flanging surfaces (2) between the nozzles (3) fit tightly to each other by connecting bolt or rivet type fasteners (7) to each other.

All manufactured GOA were tested to identify achieved technical results and compare them with the prototype. Table 1 shows the main design parameters of the generators subjected to the tests. Table 2 shows the test results of the generators corresponding to table 1.

To select the diameter of the nozzle openings and parameter K, tests of the proposed design with various nozzle diameters and parameter K were carried out (table 1 presents examples with nozzle sizes from 4 to 9 mm and parameter K from 63 to 91).

The results of measuring the zonal temperature in the jet at a distance of 0.3 and 0.7 m from the output nozzle of the generator are shown in Table 2. It can be seen that with an increase in the diameter of the nozzles more than 8 mm, the zonal temperature in the jet increases, and the temperature level in the zones near the generator increases to the greatest extent.

When the diameter of the radial nozzle is reduced to less than 5 mm, a dangerous deformation of the housing is observed, leading to its destruction.

Considering the set of characteristics that determine the configuration of the nozzle radial holes and the results of the experiments, the optimal range of hole diameters is selected in the range from 5 to 8 mm.

The ratio of the total combustion area of the end surfaces of the charges to the total cross-sectional area of the tubular nozzles (K) affects the pressure in the generator and the mode of flow of the aerosol stream through the nozzle openings. When the parameter K is less than 65 around the generator and slag nodules occur on its body, the mass of aerosol particles distributed in the protected volume decreases, i.e. the extinguishing efficiency of the generator is reduced. In addition, the effluent slag can contribute to the ignition of flammable materials in the vicinity of the generator.

At values of K greater than 90, the pressure in the generator housing causes its deformation or even destruction.

It can be seen that, at K> 90, the deformation of the body greatly increases, while at K <65, the mass loss of aerosol particles begins to increase and the fire extinguishing ability of the generator deteriorates.

Based on the results obtained, the ratio of the total combustion area of the end surfaces of the charges to the total cross-sectional area of the tubular nozzles (parameter K) within 65-90 is optimal.

Temperatures were measured using a thermoelectric cable converter КТХК 02.01-С10-И-1.5-320 / 500. The loss of aerosol solid-phase substance was determined as the ratio of the weight of slag residues adhering to the generator body after the test to the mass of the pyrotechnic charge before the test. Slag residues were cleaned from the body and weighed on an electronic balance with a division value of 0.02 g. The mass of a pyrotechnic charge was determined before testing on an electronic balance with a division value of 0.5 g.

Fire extinguishing efficiency is determined according to GOST R 53284 - 2009.

For each specified example, 3 devices were manufactured and tested. Table 2 for each parameter presents the average result for three tests.

Tests of the prototype device were carried out under the same conditions as the declared GOA. The test results for the zonal temperature in the aerosol jet and fire extinguishing efficiency are presented in Table 2.

Tests have shown the advantages of the proposed GOA in comparison with the prototype in terms of fire extinguishing efficiency and in zonal temperature in an aerosol stream at a distance of 0.7 m.

Analysis of the test results confirms that the proposed fire extinguishing aerosol generator is aimed at solving the problem and, when used, ensures the achievement of the specified technical result.

Table 1 Design parameters of tested product options Design indicators Example No. one 2 3 four 5 6 7 8 The total combustion area, cm ² 481 481 481 481 481 481 481 481 Diameter of nozzle holes, mm 6 5 8 6 8 5 9 four Number of nozzle holes 26 33 12 19 fifteen 27 eleven 44 The total area of the nozzle holes, cm ² 7.4 6.5 6.0 5.4 7.5 5.3 7.0 5.5 Parameter K 65 74 80 90 64 91 69 87

table 2 Generator Test Results Measured parameters Example No. one 2 3 four 5 6 7 8 Prototype Aerosol spray temperature at a distance of 0.3 m, ° C 183 152 243 190 235 161 271 151 215 Aerosol spray temperature at a distance of 0.7 m, ° C 75 73 94 85 89 76 103 74 130 Loss of solid phase aerosol,% 2.6 0.5 0.2 0 6.9 0 2.1 0 - Case deformation (increase in height relative to nominal),% 1.1 1.9 2.8 9.6 0.9 12.8 1.4 8 - Fire extinguishing efficiency, g / m ³ 28 28 28 28 thirty 28 28 28 45 Notes: In examples Nos. 1, 2 and 5, an abandoned GOA with a grate-type launch unit, in examples Nos. 3 and 7, an abandoned GOA with a shock-type launch unit, and in examples Nos. 4, 6 and 8, a stationary GOA with an electric starter.

Claims (8)

1. A fire extinguishing aerosol generator, comprising a housing made of two counter-mounted cup-shaped half-shells with a gap between the flanges that allows the aerosol mixture to exit, a launch unit is installed in the gap, a pyrotechnic charge is placed in each half-shell fixed to the walls of the corresponding half-shell by a carrier heat-insulating layer with the formation of free volume between the end surfaces of the charges, characterized in that the gap between the flanges It formed in the form of evenly spaced radial tubular nozzle diameter of 5 to 8 mm, with a ratio of the total area of the end faces of the combustion charge to the total sectional area of the tubular nozzles in the range 65-90, and between the nozzles provide a snug fit flange returns to each other by means of fastening elements. 2. The generator according to claim 1, characterized in that it is additionally equipped with a bracket-handle or bracket. 3. The generator according to claim 2, characterized in that the bracket-handle is installed in the location of the launch site. 4. The generator according to claim 2, characterized in that the bracket is made in the form of a trapezoid with the possibility of fastening a small base of the trapezoid to the plane of the half-housing. 5. The generator according to claim 1, characterized in that as a heat-insulating layer use a compound based on two-component silicone rubber with a filler. 6. The generator according to claim 5, characterized in that they use a filler based on calcium and / or magnesium carbonates. 7. The generator according to claim 3, characterized in that as a start node use a manual start device of a grater or percussion type. 8. The generator according to claim 4, characterized in that an electric starter is used as the start node.

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