RU2717546C1 - Device for localization of explosions of dust and gas-air mixtures in underground mine workings - Google Patents

Abstract

FIELD: soil or rock drilling; mining.

SUBSTANCE: invention relates to mining industry, in particular, to means of protection of personnel located in underground mine workings, equipment placed in them and underground mines from explosions of dust-and-air mixtures contained in atmosphere of coal mines. Device includes container 1 filled with a fire extinguishing powder, a high pressure chamber 2 placed inside the container for filling it with compressed gas, made with exhaust openings 7 extending into container 1 and overlapped by hollow piston 3, actuation mechanism, providing movement of piston 3 from high pressure chamber 2 due to pressure drop and opening of exhaust openings 7, and valve 14 communicating piston 3 with atmosphere. At that, said valve 14 is made controllable, and actuation mechanism is movable stock 8 installed in cavity of piston 3 with formation of auxiliary chamber 10, and spherical locking elements 9 retaining piston 3 due to thrust in rod 8 and releasing it when rod 8 moves into auxiliary chamber 10.

EFFECT: high reliability of operation of the device for localizing explosions and high accuracy of its operation time regardless of explosion power due to changing the design of the actuation mechanism and the principle of operation of the valve connecting the cavity of the piston to the atmosphere.

1 cl, 2 dwg

Description

The present invention relates to the mining industry, in particular, to technology and technical means of protecting production and other personnel located in underground mines, equipment located in them and the underground mines themselves from explosions of mixtures of mine gas or (and) coal dust with air (dust and gas mixtures) contained in the atmosphere of coal mines.

As you know, the goal of localizing explosions of dusty gas and air mixtures is to limit the distribution area along the underground mine workings of the flame front, which is formed as a result of these explosions and, in turn, initiates new, often more powerful explosions of these substances.

To this end, since 1930, coal shafts hazardous for gas or (and) dust began to be used first shale, and later and water barriers.

Many years of experience in operating shale and water barriers in mines in Russia and abroad have shown their lack of reliability and efficiency in the localization of explosions in gassed workings, because their operation is passive in nature, they fulfill their function only due to the energy of the shock air wave, coming from the explosion of dust and gas mixtures.

In order to increase the reliability of localization of explosions of dust and gas mixtures in coal mines, a significant number of automatic systems and devices have been developed to date that are different in terms of operation and technical implementation.

So, it is known a device that performs automatic localization and suppression of explosions of dust and gas mixtures (patent for the invention of the Russian Federation No. 2278270, IPC-2006.01 E21F 5/00, published on 06/20/2006, bull. No. 17). The device includes detectors of explosion parameters - control of a shock wave and open flame. The sensors are associated with means of degassing, obstacles and suppressing the propagation of flame and shock wave in a specific area. This device is based on the detection and suppression of flame and explosion products that have already appeared in the atmosphere, but does not have sufficient reliability for people and equipment in mining, due to the delay in actuating explosive-containing agents.

A device is known for localizing explosions of dust and gas mixtures in underground mine workings, including a tank filled with fire extinguishing powder, a high-pressure chamber placed inside the tank to fill it with compressed gas, made with exhaust openings that exit into the tank and are covered by a hollow piston, a trigger mechanism for moving the piston from the high-pressure chamber due to the pressure drop and the opening of the exhaust openings as a result, and the bypass system connecting the pore cavity nya atmosphere (RF patent №2342535, IPC-2006.01 E21F 5/00, published on 27.12.2008, Bul. №36). This device works autonomously, does not require power supply, localizes explosions of dust and gas mixtures from the weakest in the initial stage of their development to developed explosions, due to the long time spent in a suspended state of the fire extinguishing powder, dynamically ejected by the energy of compressed air (or other gas) when it is activated. However, this device has a number of significant drawbacks, the most significant of which are the technological complexity of its manufacture and low reliability due to the structural complexity of the response mechanism. The structural complexity of the triggering mechanism is expressed in the fact that it includes three mutually movable parts that require high manufacturing accuracy and a bulky connection node of the triggering mechanism with a mechanical sensor (shield) of the explosion parameters. The bypass system is an extensive network of air ducts, which significantly complicates the technology of its manufacture and requires careful monitoring of the absence of clogging of the channels. In addition, the presence in the known device of a shield that responds to excess pressure of the shock wave, mechanically rigidly connected to the trigger mechanism by means of a rod, reduces the possibility of accurately selecting the response time of the device in relation to explosions of different power.

A device is known for localizing explosions of dust and gas mixtures in underground mine workings, including a tank filled with fire extinguishing powder, a high-pressure chamber placed inside the tank to fill it with compressed gas, made with exhaust openings that exit into the tank and are covered by a hollow piston, a trigger mechanism for moving the piston from the high-pressure chamber due to the pressure drop and the opening of the exhaust holes as a result, and the valve connecting the piston cavity to the atmosphere oh (RF patent for the invention No. 2440496, IPC-2006.01 E21F 5/14, published on January 20, 2012, bull. No. 2). This device, taken as a prototype of the present invention, has a significant drawback, expressed in its insufficient speed, due to the low efficiency of the compressed gas exhaust from the high pressure chamber to the container with fire extinguishing powder due to the high aerodynamic resistance of the discharge channels and the complexity of the device settings, consisting in the need to select the pressure in a chamber corresponding to the intensity of a particular explosion. In addition, the presence in the response mechanism of an externally located sliding sleeve and therefore subject to intense loads caused by explosive processes in the mine workings significantly increases the risk of damage to this sleeve when the device is triggered, which does not provide the necessary reliability of the device in question.

The technical problem, the solution of which is provided by the present invention, is to increase the reliability of the operation of the device for localizing explosions and to ensure high accuracy of the time of its operation regardless of the power of the explosion by changing the design of the actuation mechanism and the principle of functioning of the valve connecting the piston cavity with the atmosphere.

The specified technical problem is solved in that in a device for localizing explosions of dust and gas mixtures in underground mine workings, including a tank filled with fire extinguishing powder, a high-pressure chamber placed inside the tank to fill it with compressed gas, made with exhaust openings that exit into the tank and are blocked by a hollow piston , a triggering mechanism that allows the piston to move from the high-pressure chamber due to the pressure drop and, as a result, the opening of the exhaust holes and valve connecting the piston cavity with the atmosphere, the valve is controllable, and the actuating mechanism is a movable rod installed in the piston cavity with the formation of the auxiliary chamber, and spherical locking elements holding the piston due to the stop in the rod and releasing it when moving the rod into the auxiliary chamber .

Improving the reliability of the device and improving the accuracy of its response time is achieved by simplifying their basic form of moving parts to simple cylinders, placing them completely inside the high-pressure chamber, which eliminates the occurrence of possible problems associated with their partial presence in aggressive conditions of the internal space of mine workings. Instead of a complex system of air ducts in the proposed device, the discharge of compressed air or gas occurs only through a controlled valve directly into the atmosphere. In addition, the independence of the response time of the device from the explosion power is ensured by the use of a controlled valve, the operation of which occurs with a high degree of accuracy at the moment of receipt of the control signal from the explosion sensor or from the dispatcher.

In an improved embodiment, developing the technical solution described above, to enable simultaneous refueling of the high-pressure chamber and the auxiliary chamber in one technological operation, the rod can be made with a through channel in which an additional check valve is placed.

The invention is illustrated by the following images, which show:

FIG. 1 is a longitudinal schematic section along the axis of the device for localizing explosions of dust and gas mixtures in underground mine workings;

FIG. 2 is a longitudinal schematic section along the axis of the device for localizing explosions of dusty-gas mixtures in underground mine workings - an improved embodiment.

Below are examples of specific implementations of the proposed technical solution.

The device for localizing explosions of dust and gas mixtures in underground mine workings, shown in FIG. 1 includes a container 1 filled with fire extinguishing powder, a high-pressure chamber 2 with a piston 3, and a low-pressure chamber 4. A low-pressure chamber 4 is connected to the atmosphere by a hole 5, the minimum diameter of which is unlimited, and the maximum is limited by the dimensions of the rear end 6 of the device. The hole 5 during movement of the piston 3 provides unhindered flow of atmospheric air both inside and out of the low-pressure chamber 4. In the high-pressure chamber 2 there are made radial exhaust openings 7 oriented at an angle to the longitudinal axis of the high-pressure chamber 2 towards its front part. Exhaust openings 7 connect the high-pressure chamber 2 to the internal volume of the tank 1, and in the working state of the device (in the "standby mode") are blocked by a piston 3, which is held in its original position by the actuation mechanism. The actuation mechanism is structurally completely attached to the piston 3 and is made in the form of a rod 8 moving in the longitudinal direction and spherical locking elements 9. The rod 8 is placed in the internal cavity of the piston 3 with the possibility of longitudinal movement in it along the auxiliary chamber 10, formed between the bottom 11 of the rear end of the piston 3 and the rear end 12 of the rod 8. When moving the rod 8 along the internal cavity of the piston 3 (i.e., along the auxiliary chamber 10), the bottom 11 of the rear end of the piston 3 serves as a limiter of its stroke. An opening 13 is made in the bottom 11 of the rear end face of the piston 3, into which the controlled valve 14 is fitted. The controlled valve 14 serves to fill the auxiliary chamber 10 with compressed gas (air or another working agent, for example, an inhibitor of explosive air-gas mixture) and hold the compressed gas in it up to occurrence of a control signal for operation. Spherical locking elements 9 are freely installed in the radial channels 15 of the piston 3 and fixed in them due to the stop in the shoulder 16 of the high-pressure chamber 2 on the one hand and on the outer surface of the movable rod 8. To refuel the high-pressure chamber 2 in preparation for operation, it is used nipple 17, and for monitoring the pressure in the high-pressure chamber 2 when filling it and when the device is in standby mode, the nipple and pressure gauge 18.

In an improved embodiment of the invention shown in FIG. 2, to enable refueling of the high-pressure chamber 2 and the auxiliary chamber 10 as part of one technological operation, the movable rod 8 is made with a through channel 19 in which an additional check valve 20 is placed.

To bring the device into working condition (in standby mode), the auxiliary chamber 10 is filled with compressed gas through a controlled valve 14, and then the high-pressure chamber 2 through a fitting 17 (or an additional non-return valve 20 and a through channel 19 in an improved version). After that, the controlled valve 14 will maintain a given pressure in the auxiliary chamber 10, and the rod 8 will keep the locking spherical elements 9 in the radial channels 15 from moving them into the internal cavity of the piston 3. Relying on the other hand in the shoulder 16 made in the high pressure chamber 2 due to the stepwise reduction of its diameter towards its rear, the locking spherical elements 9 keep the piston 3 from moving to the rear of the device under the influence of compressed gas pressure in the chamber pressure 2 and premature opening of the exhaust openings 7.

The device operates as follows. In an explosion of methane and / or coal dust, an air shock and a flame front propagate through the underground mine working on the sensors of the explosion parameters installed in the mine. The signal from the sensors through the corresponding switching networks (not shown in graphic images) is sent to the dispatching service of the mining enterprise and to the corresponding devices for localizing explosions.

Upon receipt of a control command from the sensor or from the dispatcher, the controlled valve 14 opens, providing unhindered outflow of compressed gas from the auxiliary chamber 10 through openings 5 and 13. Due to the pressure differential between the high-pressure chamber 2 and the internal cavity of the piston 3 in the auxiliary chamber 10, the movable rod 8 moves towards the rear end 11 of the piston 3, releasing the spherical locking elements 9. The latter rush into the cavity of the piston 3, jumping off the shoulder 16 of the high-pressure chamber 2, s thus removing the piston 3 from the stopper and allowing the latter, due to the pressure differential between the high pressure chamber 2 and the low pressure chamber 4, to shift toward the rear end 6 of the device. Due to this shift, the exhaust openings 7 are opened, the pneumatic connection between the high-pressure chamber 2 and the tank 1 is unlocked, which leads to the release of the extinguishing powder with compressed gas into the explosion zone of the dusty-gas mixture.

Claims (2)

1. A device for the localization of explosions of dust and gas mixtures in underground mine workings, including a tank filled with fire extinguishing powder, a high-pressure chamber placed inside the tank to fill it with compressed gas, made with exhaust holes that exit into the tank and are blocked by a hollow piston, a triggering mechanism that provides movement the piston from the high-pressure chamber due to the pressure drop and the opening of the exhaust holes as a result, and the valve connecting the piston cavity to the atmosphere characterized in that the valve connecting the piston cavity to the atmosphere is controllable, and the actuation mechanism is a movable rod installed in the piston cavity with the formation of an auxiliary chamber, and spherical locking elements holding the piston due to the stop in the rod and releasing the piston when moving the rod into the auxiliary chamber. 2. The device according to claim 1, characterized in that the rod is made with a through channel in which an additional check valve is placed.

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