CN215408737U - Automatic opening and closing device for blast well explosion door - Google Patents
Automatic opening and closing device for blast well explosion door Download PDFInfo
- Publication number
- CN215408737U CN215408737U CN202121640101.7U CN202121640101U CN215408737U CN 215408737 U CN215408737 U CN 215408737U CN 202121640101 U CN202121640101 U CN 202121640101U CN 215408737 U CN215408737 U CN 215408737U
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- explosion
- door
- cross beam
- closing device
- automatic opening
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- 238000004880 explosion Methods 0.000 title claims abstract description 63
- 238000003860 storage Methods 0.000 claims description 11
- 239000002775 capsule Substances 0.000 claims description 7
- 238000012806 monitoring device Methods 0.000 claims description 4
- 238000009434 installation Methods 0.000 abstract description 6
- 239000003921 oil Substances 0.000 description 39
- 239000010720 hydraulic oil Substances 0.000 description 19
- 238000000034 method Methods 0.000 description 9
- 230000008569 process Effects 0.000 description 7
- 230000006872 improvement Effects 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000010985 leather Substances 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 4
- 238000009423 ventilation Methods 0.000 description 4
- 239000003245 coal Substances 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 230000035939 shock Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 239000010705 motor oil Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002817 coal dust Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000005536 corrosion prevention Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 239000010729 system oil Substances 0.000 description 1
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Abstract
The utility model discloses an automatic opening and closing device for an explosion door of an air shaft, which comprises four stand columns uniformly arranged at the edge of a well head, wherein a first cross beam and a second cross beam are fixed between every two adjacent stand columns through bolts, a first through hole is formed in the first cross beam at the front and the back close to the two ends, a second through hole corresponding to the first through hole is formed in the second cross beam at the front and the back, a hydraulic cylinder is arranged through the first through hole and the second through hole, an inclined strut is integrally formed at the upper end of a cylinder sleeve of the hydraulic cylinder and is overlapped on the first cross beam, the explosion door is covered on the well head, an installation block is integrally formed on the explosion door, and the extending end of the hydraulic cylinder is fixed on the installation block through bolts. The utility model has the advantages that: the explosion-proof door can respond quickly and safely in case of power supply failure, and has triple insurance.
Description
Technical Field
The utility model relates to the technical field of coal mines, in particular to an automatic opening and closing device for an explosion door of an air shaft.
Background
The explosion door is arranged at the upper opening of the vertical shaft, so that the explosion door is pushed open by shock waves after explosion occurs underground to release energy, and the damage probability of the main ventilator can be reduced. When the mine is subjected to counter-wind, the pressure plate around the explosion door needs to be manually rotated to press the explosion door, so that the short circuit of wind current caused by the fact that the explosion door is lifted in the counter-wind process is prevented; the one hundred sixty rules of coal mine safety regulations stipulate that during the shutdown of a main ventilator, a wellhead explosion door and related air doors must be opened, and natural wind pressure is used for ventilation. "
At present, the explosion door of a coal mine is opened by using four steel wire ropes around the explosion door to suspend four balance weights around a pulley and using two balance adjusting devices at the south and north sides of the explosion door to lift in cooperation with a plurality of persons. The method has more defects: a first constructor stands beside the shaft for operation, and during the process of slowly lifting the explosion door, the constructor is likely to have the risk of accidental falling into the well; secondly, the two balance adjusting devices on the south and north sides of the explosion door are difficult to synchronously open, and the explosion door is easy to hang obliquely; thirdly, more manpower is needed, and if the wellhead is far away, personnel are difficult to arrive at the site in the short time of the power failure of the whole mine.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the various problems and provides an automatic opening and closing device for an air shaft explosion door, which can quickly respond and quickly and safely open the explosion door under the condition that power supply fails.
In order to solve the technical problems, the technical scheme provided by the utility model is as follows: automatic switching device of blast furnace explosion vent, including evenly installing in four stands of well head edge, two liang of adjacent all there are crossbeam one and crossbeam two through the bolt fastening between the stand, around crossbeam one is gone up and is close to both ends department and all opens through-hole one, around crossbeam two go up all open with through-hole two that a through-hole is corresponding passes through-hole one and through-hole two are equipped with the pneumatic cylinder, the cylinder liner upper end integrated into one piece of pneumatic cylinder has the bracing, the bracing take in crossbeam one is last, and the well head is covered with the explosion vent, integrated into one piece has the installation piece on the explosion vent, the pneumatic cylinder stretches out the end and passes through the bolt fastening above the installation piece.
As an improvement, a groove is formed in the first cross beam, and the inclined strut is arranged in the groove in a sunk mode.
As an improvement, the hydraulic cylinder is communicated with a hydraulic pump station, the hydraulic pump station is also communicated with a capsule energy accumulator and a storage battery, and the hydraulic cylinder is also communicated with a manual hydraulic opening system.
As an improvement, the opening height of the explosion door is 1.2m, the weight of the explosion door is 2.3t, and the diameter of the explosion door is 5.4 m.
As an improvement, the stroke of the hydraulic cylinder is 1200mm, and the cylinder diameter is 90 mm.
As an improvement, a remote monitoring device is installed on the upright post.
As a refinement, the capsule accumulator is an NXQA type capsule accumulator.
Compared with the prior art, the utility model has the advantages that: when the explosion-proof door is used, the explosion-proof door is opened and closed by adopting three modes of driving a hydraulic station opening system, an energy accumulator pressure storage opening system and a manual hydraulic pump opening system by a standby power supply (a storage battery). After power supply failure occurs, a hydraulic station starting system is driven by a standby power supply (a storage battery), if the storage battery fails, an energy accumulator pressure storage starting system can be used, and if the energy accumulator fails, no pressure can be used, a manual hydraulic pump starting system can be used, so that triple insurance is formed.
Drawings
Fig. 1 is a schematic front view of an automatic opening and closing device for an explosion vent of an air shaft according to the present invention.
Fig. 2 is a schematic top view of the automatic opening and closing device for the blast-shaft explosion vent of the present invention.
Fig. 3 is a hydraulic schematic flow chart of the automatic opening and closing device of the blast well explosion vent of the utility model.
Fig. 4 is a schematic flow diagram of hydraulic oil of the automatic opening and closing device for the blast well explosion vent of the utility model.
As shown in the figure: 1. a column; 2. a first cross beam; 3. a second cross beam; 4. a hydraulic cylinder; 5. bracing; 6. mounting blocks; 7. an explosion vent.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
With reference to the attached drawings 1-2, the automatic opening and closing device for the blast-shaft explosion door is characterized in that four upright posts 1 are installed around a wellhead to serve as supports, a first cross beam 2 and a second cross beam 3 are respectively installed on the east, west, south and north sides of the upright posts 1, and the cross beams are connected with a hydraulic cylinder 4. The mode that the connected mode adopted the buckle, is at 4 side upper ends installation bracing 5 of pneumatic cylinder, opens the round hole on crossbeam one 2 and the crossbeam two 3 promptly, and the piston rod of pneumatic cylinder 4 is transferred along the round hole, and bracing 5 presses on crossbeam one 2, and if gas, coal dust explosion take place, its shock wave can be with pneumatic cylinder 4 jack-up. The hydraulic cylinder 4 is symmetrically arranged and installed by four oil cylinders, so that the explosion door 7 is opened more stably.
Pressure storage opening system of energy accumulator
Under the condition that power is normally supplied to the hydraulic pump station, the hydraulic pump station operates to provide pressure oil for the hydraulic accumulator to enable the hydraulic accumulator to store energy, and the hydraulic pump station can stop working when the set pressure is reached. When the pressure of the energy accumulator is lower than a set value, the hydraulic pump station is enabled to reach an automatic opening state. And providing pressure oil for the energy accumulator again to enable the pressure oil to reach a set pressure value, so that the energy accumulator stores enough energy for use when the explosion door is opened.
The energy accumulator utilizes the compressibility of nitrogen to store energy, and the principle is as follows: nitrogen is filled into the leather bag, then hydraulic oil is added around the leather bag, the leather bag deforms when the hydraulic oil is continuously increased, so that the volume of the air is reduced, the air pressure inside the leather bag becomes larger and larger, and the whole energy storage process is realized.
The main parts of the capsule accumulator hydraulic operation system during operation are a three-position four-way electromagnetic valve, a hydraulic lock, a multi-path hydraulic balancer and a hydraulic oil cylinder.
With reference to fig. 4, when high-energy hydraulic oil passes through the three-position four-way electromagnetic valve, the three-position valve core can change three positions, and the four-way valve can achieve communication between intersections of four oil paths in different modes. The valve core can realize the conversion of left, middle and right positions. When the valve core is in the left position, hydraulic oil enters from the port A to the port P, and the port B is communicated with the port T; when the valve core is in the middle position, all the oil ports are not communicated with each other; when the valve core is in the right position, hydraulic oil enters from the port B and the port P, and the port A is communicated with the port T.
In order to ensure that the oil cylinders can synchronously run, the four-way hydraulic balancer supplies oil to the oil cylinders. A circuit for limiting pressure and controlling oil supplement is arranged at an outlet of the flow dividing synchronization, and when the four oil cylinders reciprocate, for example, when one of the oil cylinders is limited or blocked, the phenomenon of blocking or sucking is caused. In order to prevent the phenomenon, the pressure limiting overflow valve is subjected to overload protection according to the adjusted and set pressure value (note that the overload pressure cannot be too high and is 5-20bar higher than the rated pressure of an actuating element), and other oil cylinders are operated in place; and when (suck empty), mend oil check valve and open, prevent to suck empty and produce the danger of cavitation accordingly. When the oil cylinder performs return action under the action of high-pressure oil, the one-way throttle valve can form certain resistance to prevent the shunting from synchronously operating at the fastest speed of the hydraulic oil cylinder.
When the three-position four-way electromagnetic valve flows to the hydraulic lock, the three-position four-way electromagnetic valve flows to the four-way hydraulic balancer. The hydraulic oil flows to four lifting oil cylinders and four hydraulic oil cylinders respectively, and the hydraulic oil and the oil cylinders with the same pressure and flow are obtained simultaneously. Therefore, the explosion-proof door can stably and stably move upwards at the same speed to stably lift the explosion-proof door to open.
Referring to FIG. 3, a manual hydraulic opening system
The opening device is also provided with a set of parallel manual hydraulic opening system, and the explosion door can be conveniently, quickly and reliably opened by the manual hydraulic system after the automatic opening system fails.
The manual hydraulic pump is a small-sized hydraulic pump station that converts manual mechanical energy into hydraulic pressure energy. When the manual hydraulic pump works:
A. liquid filling: after the oil pump starts to work, oil is sequentially pressed into the high-low pressure one-way valve through the plunger and then into the oil cylinder, and when the pressure is increased to a set pressure, the low pressure valve acts to enable hydraulic oil to overflow into the oil tank.
B. Boosting pressure: during the filling process, the high pressure plunger continues to operate causing the pressure to gradually increase. When the system pressure exceeds the rated pressure, the high-pressure valve starts to act to enable the hydraulic oil to overflow into the oil tank, the pressure is always kept at the rated pressure, and the high-pressure valve is a safety valve.
C. The work is as follows: during the use process, the energy can be reduced along with the work done by the telescopic hydraulic oil cylinder. Therefore, the working pressure can be kept until the operation is finished by stepping on the pedal all the time.
D. Unloading: after the hydraulic oil pump is used, the pressure of the manual hydraulic pump is reduced to zero, the unloading valve is opened, and the hydraulic oil flows back to the oil tank.
The three processes of oil filling, pressure boosting and working are completed by stepping on the pedals.
The pump body part of the manual hydraulic pump is the main part of the oil pump and mainly comprises a high-pressure working cavity, a low-pressure working cavity, two one-way valves, a high-pressure safety valve, a low-pressure valve, an oil relief valve, two check valves, an oil inlet and the like. Wherein the holes are organically connected together according to the working state.
The model functions of the two check valves are consistent, and the two check valves are mainly used for preventing pressure hydraulic oil from flowing back to cause unstable system pressure. The low-pressure valve and the high-pressure valve are used for controlling high-pressure and low-pressure and controlling the pressure at a lower limit rated pressure and an upper limit rated pressure respectively. The check valve at the oil inlet prevents the hydraulic oil from flowing backwards through self weight and oil pressure.
Pedal part of manual hydraulic system: the pump mainly comprises a pressure lever and a pedal handle, and the pump body is connected with a plunger through a pin. The manual pedal force is applied to the pressure lever, so that the plunger can be driven up and down to do reciprocating motion, and system oil pressure is generated. And an M20 multiplied by 1.5 threaded hole is arranged on the pressure pedal handle, is used for the vertical installation of the pressure lever, and can be installed in a vertical or horizontal position for operation according to the convenience of operation.
The top of the oil tank is provided with an oil injection device and an air release device, and the air release bolt is loosened during the starting operation of the hydraulic station, so that the phenomenon that the oil pump cannot be normally used due to too low internal air pressure of the oil tank is avoided. And after the operation is finished, the deflating bolt is screwed down.
A manual hydraulic valve: the manual hydraulic combination valve consists of a three-position four-way reversing valve, two stop valves, two one-way valves, a speed regulating valve and a mounting valve.
Custom cylinder design
The customized oil cylinder is adopted for realizing the simultaneous, same-speed, stable upward running and stable running of the automatic opening of the explosion door. The hydraulic cylinder structure can be basically divided into a cylinder barrel, a cylinder cover, a piston rod, a buffer device and an exhaust device. The lower part of the explosion-proof door extends by 500mm, and the opening height of the explosion-proof door is positioned by 1.2 mm; the weight of the explosion door is 2.3 t; the diameter was 5.4 m. The effective area of the hydraulic cylinder is the working pressure or the speed ratio of the reciprocating motion selected according to the load size, so as to obtain the inner diameter of the cylinder barrel. The piston rod is selected by adopting the requirement of the outer diameter detection speed or speed ratio, and then the strength and stability of the piston rod are checked. The length of the cylinder barrel is determined by the maximum working stroke plus the width of the piston, the guide length of the piston rod, the sealing length and other factors, namely L is I + B + A + M + C. I is the maximum working length of the piston, B is the width of the piston (typically 0.6-1), a is the guide length of the piston rod, M is the piston rod seal length, which can be determined by the sealing process, and C is other lengths. Finally, the stroke of the customized oil cylinder used by the automatic explosion door opening device is 1200mm, and the diameter of the oil cylinder is 90 mm.
Remote monitoring
In order to facilitate the observation of the field situation of the operator on duty, the design scheme is provided with a set of remote monitoring device which consists of 3 network dome camera, 1 hard disk video recorder, 1 kilomega network switch, 400m network cable and a monitoring screen. The remote monitoring device can achieve video monitoring, data storage and enables a person on duty to conveniently see the field condition of the explosion-proof door so as to make correct operation.
System operating program
(1) And after receiving the instruction, the attendant opens the lock of the automatic explosion door opening and closing device on site.
(2) And closing a motor switch and starting a motor oil pump.
(3) The explosion-proof cover button is opened carefully and pressed down, the oil cylinder starts to move and is pulled up, and the explosion-proof door is opened to a set position.
(4) And after the explosion door is confirmed to be opened, the motor is closed, and a power supply recovery command is cut off.
(5) And after receiving the command of closing the explosion door, the operator on duty closes the power supply on site and starts the motor oil pump.
(6) And (4) confirming a reset button and pressing, enabling the hydraulic oil cylinder to run downwards to the closing position of the explosion-proof door, closing an oil pump motor, cutting off a power supply and replying an instruction.
The specific working process of the utility model is as follows:
the method comprises the following steps: under the main fan normal operating condition, automatic opening device can not be with explosion vent pressure jail, and the hydro-cylinder is connected with the crossbeam through the mode that adopts the buckle, can freely lift. The explosion-proof door is prevented from being opened by shock waves when the explosion happens suddenly in the well, and the ventilation facility is prevented from being damaged.
Step two: and opening the explosion-proof door. When the fan cannot operate and cannot transmit power within 10 minutes due to power failure in the well, and the explosion door needs to be opened, the automatic opening and closing device of the explosion door can realize automatic opening of the explosion door through single-person operation. The operation stroke is 1.2m, the operation time is about 40s, the operation is convenient and quick, and the safety requirement of a ventilation system is met.
Step three: and closing the explosion-proof door. According to the field experiment in earlier stage, operating personnel can one person close the operation, and the explosion vent is closed to the original position, and the operating time is not more than 40 s.
Step four: the opening and closing of the explosion door are provided with guide slideways, the explosion door is kept synchronous during vertical lifting, the horizontal error is not more than 5mm, and the transverse displacement cannot exceed 10 mm.
Step five: the explosion-proof door opening and closing device is provided with a reliable power source which is respectively a storage battery and an energy accumulator. The explosion-proof door needs to be opened after the main ventilation system is powered off, the storage battery is firstly used for supplying power to the hydraulic station, and if the storage battery fails and is not electrified, the energy accumulator can be used as a power source, so that double protection is realized. And the mechanical locking is reliable, and misoperation of personnel is prevented.
Step six: the camera shooting monitoring is installed on site, and the opening and closing state of the explosion-proof door can be remotely monitored.
Step seven: the automatic explosion vent opening device has the function of manually opening and closing the explosion vent (a manual hydraulic pump) under the condition that the related power unit of the equipment fails, the explosion vent can be opened and closed by one person independently, and the time is not more than 1 min.
The operation control part of the utility model adopts an integrated design and has the functions of wind prevention, rain prevention, corrosion prevention and the like.
The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the drawings are only one embodiment of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the utility model as defined by the appended claims.
Claims (7)
1. The automatic opening and closing device for the blast-well explosion-proof door is characterized by comprising four stand columns (1) which are uniformly arranged at the edge of a well head, a first cross beam (2) and a second cross beam (3) are fixed between every two adjacent stand columns (1) through bolts, a first through hole is formed in the first cross beam (2) close to two ends, a second through hole corresponding to the first through hole is formed in the second cross beam (3) in the front and back, a hydraulic cylinder (4) penetrates through the first through hole and the second through hole, an inclined strut (5) is integrally formed at the upper end of a cylinder sleeve of the hydraulic cylinder (4), the inclined strut (5) is arranged on the first cross beam (2), the well head is covered with an explosion-proof door (7), a mounting block (6) is integrally formed on the explosion-proof door (7), and the extending end of the hydraulic cylinder (4) is fixed onto the mounting block (6) through bolts.
2. The automatic opening and closing device of the blast-shaft explosion vent according to claim 1, characterized in that: a groove is formed in the first cross beam (2), and the inclined strut (5) is arranged in the groove in a sunk mode.
3. The automatic opening and closing device of the blast-shaft explosion vent according to claim 1, characterized in that: the hydraulic cylinder (4) is communicated with a hydraulic pump station, the hydraulic pump station is also communicated with a capsule energy accumulator and a storage battery, and the hydraulic cylinder (4) is also communicated with a manual hydraulic opening system.
4. The automatic opening and closing device of the blast-shaft explosion vent according to claim 1, characterized in that: the opening height of the explosion door (7) is 1.2m, the weight of the explosion door is 2.3t, and the diameter of the explosion door is 5.4 m.
5. The automatic opening and closing device of the blast-shaft explosion vent according to claim 1, characterized in that: the stroke of the hydraulic cylinder (4) is 1200mm, and the cylinder diameter is 90 mm.
6. The automatic opening and closing device of the blast-shaft explosion vent according to claim 1, characterized in that: and the upright post (1) is provided with a remote monitoring device.
7. The automatic opening and closing device of the blast-shaft explosion vent according to claim 3, characterized in that: the capsule energy accumulator is an NXQA type capsule energy accumulator.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202121640101.7U CN215408737U (en) | 2021-07-19 | 2021-07-19 | Automatic opening and closing device for blast well explosion door |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202121640101.7U CN215408737U (en) | 2021-07-19 | 2021-07-19 | Automatic opening and closing device for blast well explosion door |
Publications (1)
Publication Number | Publication Date |
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CN215408737U true CN215408737U (en) | 2022-01-04 |
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ID=79650565
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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CN202121640101.7U Expired - Fee Related CN215408737U (en) | 2021-07-19 | 2021-07-19 | Automatic opening and closing device for blast well explosion door |
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Country | Link |
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CN (1) | CN215408737U (en) |
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2021
- 2021-07-19 CN CN202121640101.7U patent/CN215408737U/en not_active Expired - Fee Related
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GR01 | Patent grant | ||
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CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220104 |