Coal wall supporting system and method for pulling hydraulic support

Abstract

The invention relates to the technical field of mining hydraulic supports, in particular to a coal wall supporting system and method for a hydraulic support pulling frame, and the system comprises two main valves, a single-action compensation two-way lock, a hydraulic control one-way valve, a pulling frame jack and a telescopic beam jack, wherein the two main valves are respectively connected with the pull frame jack and the telescopic beam jack through the single-action compensation two-way lock to control the pull frame jack and the telescopic beam jack to operate, and two groups of cartridge valve strings are mounted on the single-action compensation two-way lock. In a coal mine hydraulic support system, a single-action compensation two-way lock and a low-pressure compensation valve string are used, a single-action compensation two-way valve is applied, in the support pulling process, a telescopic beam jack is kept in a pressure compensation state, a telescopic beam can be kept in an action state of pressure floating on the side wall, the coal wall is prevented from falling off, and wall caving is prevented; and passive frequent opening of the safety valve on the telescopic beam jack can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic supports for mines, and in particular to a coal wall supporting system and method for hydraulic support pulling frames. Background Art

[0002] The hydraulic support for mining is an important equipment used to support and protect the mine tunnel in coal mining. It is mainly used to maintain the stability of the coal mining face, prevent the top rock from falling, ensure the safety of miners and improve the efficiency of coal mining. In the process of hydraulic support pulling in coal mines, the movement of the hydraulic support will cause the coal wall to fall off. In order to prevent this situation, the telescopic beam jack needs to be kept in a pressure-extended state. In this state, the telescopic beam jack can exert force on the side wall to prevent the occurrence of spalling. However, this also brings another problem: under continuous pressure, the safety valve of the telescopic beam jack will be opened frequently in order to maintain the system pressure stable. Frequent opening of the safety valve may cause the hydraulic system pressure to be unstable, increase the safety risk of coal mine operations, which not only increases the safety hazards, but also shortens the service life of the safety valve. Therefore, the hydraulic support system is required to maintain the force of the telescopic beam on the side wall and keep the system pressure below the setting of the safety valve, so as to prevent the occurrence of spalling and avoid the safety hazards caused by the frequent opening of the safety valve and the reduction of the life of the safety valve. Summary of the invention

[0003] In view of the above-mentioned defects and problems, the present invention provides a coal wall support system and method for hydraulic support pulling frame, aiming to solve the problem of frequent opening of the telescopic beam jack safety valve in the existing coal mine hydraulic support system, while maintaining effective support for the coal wall and preventing the coal wall from falling off.

[0004] The solution adopted by the present invention to solve its technical problems is: a coal wall support system for a hydraulic support frame, including two main valves, a single-acting compensating two-way lock, a hydraulically controlled one-way valve, and a frame jack and a telescopic beam jack, wherein the two main valves are respectively connected to the frame jack and the telescopic beam jack through the single-acting compensating two-way lock to control the operation of the frame jack and the telescopic beam jack, and the single-acting compensating two-way lock is equipped with two groups of cartridge valve strings, namely the right-side cartridge valve string and the left-side cartridge valve string, and the single-acting compensating two-way lock is equipped with a low-pressure compensating valve string, and the single-acting compensating two-way lock realizes pressure compensation of the frame jack and the telescopic beam jack through the action of the cartridge valve string and the low-pressure compensating valve string.

[0005] Furthermore, the single-acting compensating two-way lock is provided with two liquid inlets PA and PB, one hydraulic control port Z and two liquid outlets A and B; the liquid inlets PA and PB are respectively connected to the two liquid outlets of the main valve, the liquid outlets A and B are respectively connected to the piston chamber of the telescopic beam jack and the piston rod chamber of the telescopic beam jack, the Z port of the single-acting compensating two-way lock is connected to the piston chamber of the rack jack through a hydraulically controlled one-way valve, the liquid inlet of the hydraulically controlled one-way valve is simultaneously connected to the liquid outlet A of the main valve, the liquid outlet is connected to the piston chamber of the rack jack, the control port is connected to the liquid outlet B of the main valve, and is simultaneously connected to the piston rod chamber of the rack jack; a small one-way valve is provided in the single-acting compensating two-way lock, the right-side cartridge valve string is connected to the liquid inlets PA, PB and liquid outlet A through the small one-way valve and the low-pressure compensation valve string, and the left-side cartridge valve string is connected to the liquid inlets PA, PB and liquid outlet B.

[0006] Furthermore, two valve ports A1 and B1 are provided on the other side of the single-acting compensating bidirectional lock, the liquid outlet A is connected to the valve port A1, the liquid outlet B is connected to the valve port B1, and the valve ports A1 and B1 are also connected to safety valves 4 respectively.

[0007] Furthermore, the cartridge valve string 5 adopts a FDY125 cartridge valve string.

[0008] A supporting method based on the coal wall supporting system according to claim 1, characterized in that the supporting is performed by the following method: When the telescopic beam jack is in normal operation, liquid enters the PA port and enters the control chamber of the left cartridge valve string to unlock the left cartridge valve string. At the same time, high-pressure liquid flows through the small one-way valve and the low-pressure compensation valve string to open the right cartridge valve string and flows out from the A port to enter the piston chamber of the telescopic beam jack to control the extension of the telescopic beam jack. When liquid enters the PB port, high-pressure liquid enters the control chamber of the right cartridge valve string to unlock the right cartridge valve string and opens the left cartridge valve string to flow out from the B port to enter the piston rod chamber of the telescopic beam jack to control the retraction of the telescopic beam jack and realize the normal operation of the telescopic beam jack. When the frame is pulled, the main valve controlling the frame jack is opened, and the high-pressure liquid passes through the hydraulically controlled one-way valve and enters the piston chamber of the frame jack. The liquid on one side enters from the Z port of the single-acting compensation two-way lock, unlocking the right-side cartridge valve string connected to the A port. The high-pressure liquid in the piston chamber of the telescopic beam jack flows through the right-side cartridge valve string, the low-pressure compensation valve string, and finally flows out from the PA port. The piston chamber of the telescopic beam jack is unloaded from the A port, keeping the piston chamber of the telescopic beam jack under the compensation pressure. At the same time, the single-acting compensation two-way lock, under the action of the low-pressure compensation valve string, keeps the piston chamber pressure of the telescopic beam jack floating and adjustable, keeping the telescopic beam jack in an extended state, and there is an effective resistance between the telescopic beam jack and the side wall, so that when the frame jack is pulled, the safety valve of the telescopic beam jack will not be opened frequently, and the telescopic beam jack is in a piston rod extended state to prevent the coal seam rock wall from falling off.

[0009] Furthermore, the operating range of the low-pressure compensation valve string is 6-11 MPa.

[0010] The beneficial effects of the present invention are as follows: in a coal mine hydraulic support system, by using a single-acting compensating two-way lock and a low-pressure compensating valve string and a single-acting compensating two-way valve method, during the frame pulling process, the telescopic beam jack is kept in a state of pressure compensation, which can not only keep the telescopic beam in a state of action on the floating pressure of the side wall, prevent the coal wall from falling off, prevent the occurrence of slabs, but also avoid the passive and frequent opening of the safety valve on the telescopic beam jack. The present invention can effectively reduce the opening frequency of the safety valve of the telescopic beam jack, reduce the safety hazards caused by unstable pressure, and at the same time does not affect the independent action of the telescopic beam jack, thereby improving the safety of coal mine operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a system connection diagram of the present invention; Figure 2 This is a functional principle diagram of a single-acting compensating two-way lock of the present invention; Figure 3 This is a front view of the single-acting compensating two-way lock of the present invention; Figure 4 It is a right view of the single-acting compensating two-way lock of the present invention; Figure 5 It is the AA cross-sectional view of the present invention; Figure 6 It is the BB cross-sectional view of the present invention; Figure 7 It is a schematic diagram of the structure of the rack jack and the telescopic beam jack of the present invention; Figure 8 It is a front view of the single-acting compensating two-way lock of the present invention; Fig. 9 It is a rear view of the single-acting compensating two-way lock of the present invention; Fig.10 This is a usage state diagram of the present invention.

[0012] In the figure: 1. Tension frame jack; 11. Tension frame jack piston rod chamber; 12. Tension frame jack piston chamber; 2. Telescopic beam jack; 21. Telescopic beam jack piston chamber; 22. Telescopic beam jack piston rod chamber; 3. Single-acting compensation two-way lock; 31. Liquid inlet; 32. Hydraulic control port; 33. Liquid outlet; 34. Valve port; 4. Safety valve; 5. Cartridge valve string; 51. Left-side cartridge valve string; 52. Right-side cartridge valve string; 6. Low-pressure compensation valve string; 7. Main valve; 8. Hydraulic control check valve. DETAILED DESCRIPTION

[0013] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0014] See also Figure 1-10 The present invention provides a technical solution of a coal wall support system and method for a hydraulic support puller: Embodiment 1: This embodiment provides a coal wall support system with a hydraulic support puller according to Figure 1 As shown, the system of the present invention includes two main valves 7, a single-acting compensating two-way lock 3, a hydraulically controlled one-way valve 8, two safety valves 4, and a telescopic frame jack 1 and a telescopic beam jack 2, wherein the two main valves 7 are respectively connected to the telescopic frame jack 1 and the telescopic beam jack 2 through the single-acting compensating two-way lock 3 to control the operation of the telescopic frame jack and the telescopic beam jack.

[0015] according to Figure 2 - Fig. 9 As shown, one side of the single-acting compensating two-way lock 3 is provided with two liquid inlets 31 (PA and PB) and a hydraulic control port 32 (Z), and the other side is provided with two valve ports 34 (A1 and B1). Two liquid outlets 33 (A and B) are provided at the front end, and the liquid outlet A is connected to the valve port A1, and the liquid outlet B is connected to the valve port B1. The liquid inlets PA and PB of the single-acting compensating two-way lock 3 are respectively connected to the two liquid outlets of the main valve 7, and the two liquid outlets A and B of the single-acting compensating two-way lock are respectively connected to the telescopic beam jack piston chamber 21 and the telescopic beam jack piston rod chamber 22, that is, the A port is connected to the telescopic beam jack piston chamber 21, and the B port is connected to the telescopic beam jack piston rod chamber 22, and it is ensured that the single-acting compensating two-way lock 3 has a low-pressure compensation side flow channel connected to the telescopic beam jack piston chamber 21, and the valve port A of the single-acting compensating two-way lock 3 1. Two safety valves 4 are also connected at B1 respectively. The Z port of the single-acting compensation two-way lock 3, that is, the control port of the valve string that can unlock the low-pressure compensation side, is connected to the liquid inlet of the hydraulically controlled one-way valve 8, and then the Z port is connected to the piston chamber 12 of the rack jack. The liquid inlet of the hydraulically controlled one-way valve 8 is also connected to the liquid outlet A of the main valve 7, and the liquid outlet of the hydraulically controlled one-way valve 8 is connected to the piston chamber 12 of the rack jack. The control port of the hydraulically controlled one-way valve 8 is connected to the liquid outlet B of the main valve 7, and is also connected to the piston rod chamber 22 of the rack jack.

[0016] Two groups of cartridge valve strings 5 ​​are installed on the single-acting compensation bidirectional lock 3, which are the right cartridge valve string 52 and the left cartridge valve string 51. The right cartridge valve string 52 is connected to the liquid inlet PA, PB and the liquid outlet A through a small one-way valve and a low-pressure compensation valve string 6, and the left cartridge valve string 51 is connected to the liquid inlet PA, PB and the liquid outlet B; the cartridge valve string 5 adopts the FDY125 cartridge valve string.

[0017] A low-pressure compensation valve string 6 is installed on the single-acting compensation bidirectional lock 3, and a small one-way valve is arranged inside the single-acting compensation bidirectional lock 3, the liquid inlet of the small one-way valve is connected to the liquid inlet PA and the low-pressure compensation valve string 6, the liquid inlet of the low-pressure compensation valve string 6 is connected to the liquid outlet of the small one-way valve, and the liquid outlet of the low-pressure compensation valve string 6 is connected to the right-side cartridge valve string 52.

[0018] When the telescopic beam jack 2 is in normal operation, if liquid enters the liquid inlet PA, it enters the control chamber of the left cartridge valve string 51, unlocking the left cartridge valve string 51. At the same time, the high-pressure liquid flows through the small one-way valve and the low-pressure compensation valve string 6, opens the right cartridge valve string 52, flows out from the A port, enters the telescopic beam jack piston chamber 21, and controls the extension of the telescopic beam jack; when liquid enters PB, the high-pressure liquid enters the control chamber of the right cartridge valve string, unlocking the right cartridge valve string 52, and opens the left cartridge valve string 51, flows out from the B port, enters the telescopic beam jack piston rod chamber, controls the retraction of the telescopic beam jack, and realizes the normal operation of the telescopic beam jack.

[0019] Embodiment 2: This embodiment provides a coal wall support method for hydraulic support support When the frame is pulled, the main valve of the telescopic beam jack 1 is opened, and the high-pressure liquid passes through the hydraulically controlled one-way valve 8 and enters the piston chamber of the telescopic beam jack. The piston chamber 12 of the telescopic beam jack enters the liquid, and the liquid on one side enters from the Z port of the single-acting compensation two-way lock 3, unlocking the right-side cartridge valve string 52 connected to the A port, and then the A port of the single-acting compensation two-way lock 3 is unlocked by high pressure. The high-pressure liquid in the piston chamber 21 of the telescopic beam jack flows through the right-side cartridge valve string 52 and the low-pressure compensation valve string 6, and finally flows out from the PA port. The piston chamber of the telescopic beam jack is connected to the A port. The mouth is unloaded, so that the piston chamber 21 of the telescopic beam jack is kept under the compensation pressure. At the same time, the single-acting compensation two-way lock 3 keeps the floating adjustable pressure of the telescopic beam jack piston chamber at 6-11MPa under the action of the low-pressure compensation valve string 6. In this way, the telescopic beam jack can be kept in an extended state, and there is an action resistance between the telescopic beam jack and the side wall. Therefore, when the pulling frame jack is pulling the frame, the safety valve 4 of the telescopic beam jack 2 will not be opened frequently, and the telescopic beam jack is in a piston rod extended state to prevent the coal seam rock wall from falling off.

[0020] The low-pressure compensation valve series works at 6-11MPa. This pressure is not a fixed value and can be flexibly adjusted according to actual production needs.

[0021] Embodiment three: The technical solution of the present invention can also be used between the balancing jack and the column jack to keep the safety valve of the balancing jack from opening during the column lifting process; it can also be used between the pulling frame jack and the guard jack to keep the safety valve of the guard jack from opening during the pulling frame process. This solution can be adopted in any system that requires pressure floating compensation in the hydraulic support.

[0022] The above description is only a preferred embodiment of the present invention and does not limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A coal wall support system for hydraulic support pulling frame, characterized in that: The system includes two main valves, a single-acting compensating two-way lock, a hydraulically controlled one-way valve, a frame jack and a telescopic beam jack, wherein the two main valves are respectively connected to the frame jack and the telescopic beam jack through the single-acting compensating two-way lock to control the operation of the frame jack and the telescopic beam jack, the single-acting compensating two-way lock is equipped with two groups of cartridge valve strings, namely the right-side cartridge valve string and the left-side cartridge valve string, and the single-acting compensating two-way lock is equipped with a low-pressure compensation valve string, and the single-acting compensating two-way lock realizes pressure compensation of the frame of the frame jack and the telescopic beam jack through the action of the cartridge valve string and the low-pressure compensation valve string.

2. A coal wall support system and method for hydraulic support pulling frame according to claim 1, characterized in that: The single-acting compensating two-way lock is provided with two liquid inlets PA and PB, a hydraulic control port Z and two liquid outlets A and B; the liquid inlets PA and PB are respectively connected to the two liquid outlets of the main valve, and the liquid outlets A and B are respectively connected to the piston chamber of the telescopic beam jack and the piston rod chamber of the telescopic beam jack, and the Z port of the single-acting compensating two-way lock is connected to the piston chamber of the rack jack through a hydraulically controlled one-way valve, and the liquid inlet of the hydraulically controlled one-way valve is simultaneously connected to the liquid outlet A of the main valve, and the liquid outlet is connected to the piston chamber of the rack jack, and the control port is connected to the liquid outlet B of the main valve, and is simultaneously connected to the piston rod chamber of the rack jack; a small one-way valve is provided in the single-acting compensating two-way lock, and the right-side cartridge valve string is connected to the liquid inlets PA, PB and liquid outlet A through the small one-way valve and the low-pressure compensation valve string, and the left-side cartridge valve string is connected to the liquid inlets PA, PB and liquid outlet B.

3. A coal wall support system and method for hydraulic support pulling frame according to claim 1, characterized in that: The other side of the single-acting compensating bidirectional lock is provided with two valve ports A1 and B1, the liquid outlet A is connected to the valve port A1, the liquid outlet B is connected to the valve port B1, and the valve ports A1 and B1 are also connected to safety valves 4 respectively.

4. A coal wall support system and method for hydraulic support pulling frame according to claim 1, characterized in that: The cartridge valve string 5 adopts the FDY125 cartridge valve string.

5. A supporting method based on the coal wall supporting system according to claim 1, characterized in that: Support is provided by: When the telescopic beam jack is in normal operation, liquid enters the PA port and enters the control chamber of the left cartridge valve string to unlock the left cartridge valve string. At the same time, high-pressure liquid flows through the small one-way valve and the low-pressure compensation valve string to open the right cartridge valve string and flows out from the A port to enter the piston chamber of the telescopic beam jack to control the extension of the telescopic beam jack. When liquid enters the PB port, high-pressure liquid enters the control chamber of the right cartridge valve string to unlock the right cartridge valve string and opens the left cartridge valve string to flow out from the B port to enter the piston rod chamber of the telescopic beam jack to control the retraction of the telescopic beam jack and realize the normal operation of the telescopic beam jack. When the frame is pulled, the main valve controlling the frame jack is opened, and the high-pressure liquid passes through the hydraulically controlled one-way valve and enters the piston chamber of the frame jack. The liquid on one side enters from the Z port of the single-acting compensation two-way lock, unlocking the right-side cartridge valve string connected to the A port. The high-pressure liquid in the piston chamber of the telescopic beam jack flows through the right-side cartridge valve string, the low-pressure compensation valve string, and finally flows out from the PA port. The piston chamber of the telescopic beam jack is unloaded from the A port, keeping the piston chamber of the telescopic beam jack under the compensation pressure. At the same time, the single-acting compensation two-way lock, under the action of the low-pressure compensation valve string, keeps the piston chamber pressure of the telescopic beam jack floating and adjustable, keeping the telescopic beam jack in an extended state, and there is an effective resistance between the telescopic beam jack and the side wall, so that when the frame jack is pulled, the safety valve of the telescopic beam jack will not be opened frequently, and the telescopic beam jack is in a piston rod extended state to prevent the coal seam rock wall from falling off.

6. The coal wall supporting method according to claim 5, characterized in that: The operating range of the low-pressure compensation valve series is 6-11 MPa.

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