CN214145369U - Coal seam hydraulic pressure relief hole protecting drill - Google Patents

Abstract

The utility model belongs to the technical field of coal mining exploration safety, a coal seam water conservancy release hole protection bores is disclosed, include inner joint, outer joint, high-low pressure switching mechanism, can open formula core and broach shell. The beneficial effects are that: the structure is simple, the reliability is high, the drilling technology is favorably improved, the pore-forming quality is improved, the hole protection rate of the drilled hole is improved, the construction process is simplified, the blank zone of gas extraction is favorably reduced, the gas extraction efficiency is improved, the effective drilling extraction period is prolonged, and the safe production of a mine is ensured.

Description

Coal seam hydraulic pressure relief hole protecting drill

Technical Field

The utility model relates to a coal mining exploration safety technical field especially relates to a coal seam water conservancy release hole protecting drill.

Background

China is the world's largest coal producing and consuming country. Most coal seams in China have the characteristics of heterogeneity, microporosity, low permeability and high adsorption, and the low permeability and the heterogeneity of the coal seams make the gas difficult to extract effectively. However, for a single outburst coal seam or an outburst coal seam first mining layer without protective layer mining conditions, the method of pre-extracting coal seam gas by drilling through a layer is a main gas control method. In order to improve the gas extraction rate of the coal seam, shorten the pre-extraction time and reduce the number of drilled holes, measures must be taken to increase the gas permeability of the coal seam. In recent years, researchers have proposed various methods for relieving pressure and increasing permeability of drill holes, and the most important is hydraulic pressure relieving and permeability increasing technology, such as hydraulic cutting and hydraulic punching. The main principle of the method is that high-pressure water is used as a hydraulic measure of power, a pressure relief space and secondary fractures are formed by destroying and damaging coal bodies in drill holes, so that the coal rock bodies are deformed and displaced, and the purposes of pressure relief and permeability increase of a coal reservoir are achieved.

Although many hydraulic punching and slotting equipment for mines already exist at home and abroad, the existing equipment still has some problems, mainly including:

(1) the existing hydraulic punching and slotting device for the mine is immature, a punching drill bit needs to be replaced after the drill is withdrawn, the punching operation cannot be efficiently carried out, problems are easy to occur, and the hydraulic punching and slotting device is still not popularized and applied in coal mines.

(2) The middle of the existing hydraulic punching and slotting equipment for mines cannot pass through a sieve tube and has no hole protection function, after drilling and hole forming, a drill is firstly withdrawn, and then the hole protection sieve tube is put down, however, the occurrence of a coal seam is complicated and changeable, the softness and hardness of a coal body structure are uneven, hole collapse is easily formed for a soft coal seam, the sieve tube of the hydraulic pressure relief and permeability increasing technology cannot be completely plugged into the end of a drilled hole, the process requirement of coal mine extraction cannot be met, and the pressure relief effect is difficult to guarantee.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an easy operation, strong adaptability, easy-to-use convenient coal seam water conservancy release hole protection bores.

In order to achieve the purpose, the utility model is implemented according to the following technical scheme: a coal seam hydraulic pressure relief hole protection drill comprises an inner joint, an outer joint, a high-low pressure switching mechanism, an openable core body and a cutter sleeve, wherein the inner joint and the outer joint are respectively arranged at two ends of the cutter sleeve and are respectively connected with the cutter sleeve through threads; the inner joint, the outer joint and the knife sleeve are all provided with water-through inner cavities,

the high-low pressure switching mechanism comprises a piston and a switching sleeve, the switching sleeve is movably connected with the inner wall of the inner joint in a sealing manner, and a high-pressure nozzle communicated with the water-passing inner cavity is arranged on the side wall of the inner joint; the piston comprises a return spring and a pressure head, the return spring is limited and fixed in a water-through inner cavity of the outer joint, the pressure head is in a hollow shaft shape, an outward protruding shaft shoulder is arranged in the middle of the outer wall of the pressure head, the front end face of the pressure head is in compression joint with one end of the return spring, and a hole shoulder matched with the shaft shoulder of the pressure head is arranged in the water-through inner cavity of the outer joint; a low-pressure water through hole leading from the outer wall to the center is formed in the shaft body between the front end surface of the pressure head and the shaft shoulder;

the openable core comprises a hollow shell, a low-pressure water passing gap is arranged between the outer wall of the hollow shell and the cutter sleeve, and an openable valve body is arranged in the hollow shell;

the rear end face of the pressure head is coaxially connected with the front end face of the hollow shell in a limiting contact manner and is fixedly connected with the front end face of the valve body; the front part of the switching sleeve is fixedly connected with the rear end face of the hollow shell.

Preferably, the valve body comprises a spherical valve core and a valve core control switch, the valve core control switch comprises an unlocking sleeve, an unlocking spring, a valve core fixing sleeve and an unlocking mechanism, the front end face of the valve core fixing sleeve is in limit sealing contact with the inner cavity of the hollow shell, the front end face of the valve core fixing sleeve is provided with a hollow threaded shaft, the front end face of the valve core fixing sleeve is in threaded connection with the rear end of a pressure head through the hollow threaded shaft, the unlocking spring is sleeved at the front part of the outer wall of the valve core fixing sleeve, the front end face of the unlocking spring is in limit contact with the inner cavity of the hollow shell, the upper end and the lower end of the valve core are respectively provided with a valve rod, and the valve core is arranged in the valve core fixing sleeve and is in rotary connection with the valve core fixing sleeve through the valve rods at the two ends; two valve rods of the valve core respectively extend outwards and are provided with concentric gears; the unlocking sleeve is partially sleeved at the rear part of the outer wall of the valve core fixing sleeve, a water passing gap is formed between the outer wall of the unlocking sleeve and the inner wall of the hollow shell, and the middle part of the hollow shell is provided with a low-pressure water passing through hole communicated with the inner wall and the outer wall; two long grooves are formed in the outer wall of the front part of the unlocking sleeve, gears on two valve rods of the valve core are respectively and correspondingly arranged in one long groove, and a straight rack meshed with the gears is respectively and fixedly arranged on the side wall of one side of each of the two long grooves; the rear end face of the unlocking spring is in contact connection with the front end face of the unlocking sleeve;

the unlocking mechanism comprises a plurality of long holes which are uniformly distributed on the circumferential direction of the side wall of the front part of the unlocking sleeve, and locking plates, pin shafts and torsional springs, wherein the number of the locking plates corresponds to that of the long holes; an annular groove is formed in the inner wall of the rear part of the hollow shell;

in an initial state, the unlocking spring is in a compressed state, the outer ends of the locking plates are abutted against the inner wall of the annular groove of the hollow shell under the action of the torsion spring, the valve core is in a closed state, and the diameter of a circular area defined by the inner end faces of the locking plates is smaller than the outer diameter of the sieve tube; under the open mode, the unblock spring resets, and the spur rack in the unblock sleeve drives the gear rotation on the case, and then drives the case and opens, and the outer end of locking plate is contradicted on the inner wall of cavity casing, and the circular regional diameter more than or equal to screen pipe external diameter that the inner terminal surface of a plurality of locking plates encloses.

Preferably, the inner joint is provided with an inner conical thread section in threaded connection with the hollow drill rod; the outer joint is provided with an outer cone thread section connected with the drill bit thread.

The working principle of this application does: 1. according to the water inlet pressure, the high-low pressure switching mechanism can switch the water paths of high-pressure water and low-pressure water; 2. after the punching operation, when needing to go out the screen pipe, the locking plate is when receiving the screen pipe front end top to push, and the locking plate can be propped open under the torsional spring effect, and the locking plate outer end breaks away from the annular groove inner wall of cavity casing, and under the effect of unblock spring, the unlocking sleeve passes backward, and the spur rack in the unlocking sleeve drives the gear rotation on the case, and then drives the case and opens, later transfers of protecting the hole screen pipe. Therefore, after hydraulic punching, the protective hole sieve tube can be quickly lowered in the whole process without withdrawing the drill. The problem of hole collapse of the drilling hole of the soft coal seam is solved by directly setting the sieve tube protective hole without withdrawing the drill after the hole is formed by drilling, the problems of the setting depth of the sieve tube and the low efficiency of the sieve tube with a naked hole after the hole is withdrawn are solved, and the gas extraction effect and the construction efficiency are improved.

The beneficial effect of this application does: the structure is simple, the reliability is high, the drilling technology is favorably improved, the pore-forming quality is improved, and the qualified rate of drilled holes is improved, so that the offset distance of the drilled holes is reduced, the blank zone of gas extraction is favorably reduced, the gas extraction effect is improved, and the safe production of a mine is ensured.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural diagram of the valve body of the present invention in a closed state.

Fig. 3 is a view a-a of fig. 2.

Fig. 4 is a schematic structural diagram of the open state of the valve body of the present invention.

Fig. 5 is a view B-B of fig. 4.

Fig. 6 is a schematic view of the state of the present invention in a low pressure water state.

Fig. 7 is a schematic diagram of the state of the present invention in the high pressure water state.

Fig. 8 is a schematic view of the screen pipe in the state of the present invention.

Detailed Description

The invention will be further described with reference to the drawings and specific embodiments, illustrative embodiments and description of which are provided herein to explain the invention, but not as a limitation thereof.

The coal seam hydraulic pressure relief hole protection drill shown in fig. 1 comprises an inner joint 1, an outer joint 2, a high-low pressure switching mechanism, an openable core body 3 and a cutter sleeve 4, wherein the inner joint and the outer joint are respectively arranged at two ends of the cutter sleeve and are respectively in threaded connection with the cutter sleeve; the inner joint, the outer joint and the knife sleeve are all provided with water-through inner cavities,

the high-low pressure switching mechanism comprises a piston and a switching sleeve 6, the switching sleeve is movably connected with the inner wall of the inner joint in a sealing way, and a high-pressure nozzle 7 communicated with the water-through inner cavity is arranged on the side wall of the inner joint; the piston comprises a return spring 8 and a pressure head 9, the return spring is limited and fixed in a water-through inner cavity of the outer joint, the pressure head is in a hollow shaft shape, an outward protruding shaft shoulder is arranged in the middle of the outer wall of the pressure head, the front end face of the pressure head is in press connection with one end of the return spring, and a hole shoulder matched with the shaft shoulder of the pressure head is arranged in the water-through inner cavity of the outer joint; a low-pressure water through hole 10 leading to the center from the outer wall is arranged on the shaft body between the front end surface of the pressure head and the shaft shoulder;

the openable core body 3 comprises a hollow shell 301, a first low-pressure water passing gap 302 is arranged between the outer wall of the hollow shell and a cutter sleeve, and an openable valve body 303 is arranged in the hollow shell;

the rear end face of the pressure head is coaxially connected with the front end face of the hollow shell in a limiting contact manner and is fixedly connected with the front end face of the valve body; the front part of the switching sleeve is fixedly connected with the rear end face of the hollow shell.

Specifically, as shown in fig. 2 and fig. 3, the valve body 303 includes a spherical valve core 3031 and a valve core control switch, the valve core control switch includes an unlocking sleeve 3032, an unlocking spring 3033, a valve core fixing sleeve 3034 and an unlocking mechanism, the front end surface of the valve core fixing sleeve is in limit sealing contact with the inner cavity of the hollow housing, the front end surface of the valve core fixing sleeve is provided with a hollow threaded shaft 15, the front end surface of the valve core fixing sleeve is in limit sealing contact with the rear end of the pressure head through the hollow threaded shaft, the unlocking spring is sleeved on the front part of the outer wall of the valve core fixing sleeve, the front end surface of the unlocking spring is in limit contact with the inner cavity of the hollow housing, the upper and lower ends of the valve core are respectively provided with a valve rod 3035, and the valve core is arranged in the valve core fixing sleeve and is rotatably connected with the valve core fixing sleeve through the valve rods at the two ends; the two valve rods of the valve core respectively extend outwards and are provided with concentric gears 3036; the unlocking sleeve part is sleeved at the rear part of the outer wall of the valve core fixing sleeve, a second low-pressure water passing gap 3037 is arranged between the outer wall of the unlocking sleeve and the inner wall of the hollow shell, and a low-pressure water passing through hole 3038 for communicating the first low-pressure water passing gap with the second low-pressure water passing gap is arranged in the middle of the hollow shell; two long grooves are formed in the outer wall of the front part of the unlocking sleeve, gears on two valve rods of the valve core are respectively and correspondingly arranged in one long groove, and a straight rack 3039 meshed with the gears is fixedly arranged on the side wall of one side of each of the two long grooves; the rear end face of the unlocking spring is in contact connection with the front end face of the unlocking sleeve;

the unlocking mechanism comprises a plurality of long holes 11 which are uniformly distributed on the circumferential direction of the side wall of the front part of the unlocking sleeve, and locking plates 12, pin shafts 13 and torsion springs 14, wherein the number of the locking plates corresponds to the number of the long holes; an annular groove 3011 is formed in the inner wall of the rear portion of the hollow shell 301;

in an initial state, the unlocking spring is in a compressed state, the outer ends of the locking plates are abutted against the inner wall of the annular groove of the hollow shell under the action of the torsion spring, the valve core is in a closed state, and the diameter of a circular area defined by the inner end faces of the locking plates is smaller than the outer diameter of the sieve tube (the dotted circle in the middle of the sieve tube in fig. 3 is the outer contour of the sieve tube);

as shown in fig. 4 and 5, in the open state, the unlocking spring is reset, the spur rack in the unlocking sleeve drives the gear on the valve core to rotate, and further drives the valve core to open, the outer ends of the locking plates are abutted against the inner wall of the hollow shell, and the diameter of the circular area surrounded by the inner end faces of the locking plates is larger than or equal to the outer diameter of the sieve tube.

Specifically, the inner joint is provided with an inner conical thread section in threaded connection with the hollow drill rod; the outer joint is provided with an outer cone thread section connected with the drill bit thread.

The specific use method of the embodiment is as follows: when the coal seam hydraulic pressure relief hole protection drill is used, the outer joint is in threaded connection with the hollow drill bit, the inner joint is in threaded connection with the hollow auger stem, as shown in fig. 6 (the drill bit and the drill stem are omitted in fig. 6), in the drilling process of the drill, compressed air or low-pressure water is introduced to discharge powder and slag, the arrow direction in the drawing is a low-pressure water traveling path (the compressed air path is the same as the low-pressure water path and is omitted), under the action of the low-pressure water, the pressure head is pushed to compress the reset spring 8, the shaft shoulder of the pressure head is positioned between the point C and the point D, so that the low-pressure water can pass through, meanwhile, in the process, the pressure head 9 drives the openable core body 3 and the switching sleeve 6 to integrally move forwards, and at the moment, the valve body in the openable core body 3 is in a closed state; in this process, the path of the low-pressure water flow is the nipple 1 → the switching sleeve 6 → the second low-pressure water passing gap 3037 → the low-pressure water passing through hole 3038 → the first low-pressure water passing gap 302 → the low-pressure water passing hole 10 → the outer nipple 2;

the construction process of punching while punching is adopted, a clean water pump is started when a drilling machine drills to a first punching point, the water inlet pressure is improved, and the hydraulic punching and slotting mode is started when the water pressure reaches a high pressure of more than 6 MPa. As shown in fig. 7, the high-pressure water pushes the ram to press the ram shoulder against the point D, at this time, the low-pressure water on the ram is sealed through the sealing member 10, the ram 9 drives the openable core 3 and the switching sleeve 6 to move forward integrally, the high-pressure nozzle 7 is exposed, and the high-pressure water is sprayed out from the high-pressure nozzle 7 (the arrow indicates the water flow direction) to perform hydraulic punching and slotting. In this state, the valve body in the openable core 3 is in a closed state.

After the punching and slotting are finished, the drill rod is lifted to be 2m away from the bottom of the hole without withdrawing the drill, the high-pressure water whip is removed, and the sieve tube is put in. The screen pipe front end is the taper shape, as shown in fig. 4 fig. 5 fig. 8, when the screen pipe front end supports locking plate 12 of unlocking mechanism, the screen pipe head pushes locking plate 12, the locking plate rotates around the pin roll, break away from being provided with annular groove 3011 from hollow casing 301 rear portion inner wall, later, under the reply of unblock spring, the unlocking sleeve moves backward, the straight tooth belt on it moves the gear on the case and rotates, and then drive the case and open, the outer end of locking plate is supported on the inner wall of hollow casing, the circular region diameter that the inner terminal surface of a plurality of locking plates encloses is more than or equal to the screen pipe external diameter. And then, the sieve tube can go deep into the drill hole through the drill bit from the coal seam hydraulic pressure relief hole-protecting drill, and a 'dovetail' wing piece of the sieve tube hole bottom suspension device is opened and inversely hung on the hole wall, so that the sieve tube can be fixed at the hole bottom. And (3) keeping the average running depth of the hole-protecting sieve tube to be more than 95% of the hole depth, finally, keeping the sieve tube in the hole, rapidly sealing the hole, connecting and pumping, and carrying out tag hanging management on the drilled hole according to the drilling construction and hole sealing conditions.

The technical scheme of the utility model is not limited to the restriction of above-mentioned specific embodiment, all according to the utility model discloses a technical scheme makes technical deformation, all falls into within the protection scope of the utility model.

Claims (3)

1. The utility model provides a coal seam water conservancy release hole protection bores which characterized in that: the tool comprises an inner joint, an outer joint, a high-low pressure switching mechanism, an openable core body and a tool sleeve, wherein the inner joint and the outer joint are respectively arranged at two ends of the tool sleeve and are respectively connected with the tool sleeve through threads; the inner joint, the outer joint and the knife sleeve are all provided with water-through inner cavities,

the high-low pressure switching mechanism comprises a piston and a switching sleeve, the switching sleeve is movably connected with the inner wall of the inner joint in a sealing manner, and a high-pressure nozzle communicated with the water-passing inner cavity is arranged on the side wall of the inner joint; the piston comprises a return spring and a pressure head, the return spring is limited and fixed in a water-through inner cavity of the outer joint, the pressure head is in a hollow shaft shape, an outward protruding shaft shoulder is arranged in the middle of the outer wall of the pressure head, the front end face of the pressure head is in compression joint with one end of the return spring, and a hole shoulder matched with the shaft shoulder of the pressure head is arranged in the water-through inner cavity of the outer joint; a low-pressure water through hole leading from the outer wall to the center is formed in the shaft body between the front end surface of the pressure head and the shaft shoulder;

the openable core comprises a hollow shell, a low-pressure water passing gap is arranged between the outer wall of the hollow shell and the cutter sleeve, and an openable valve body is arranged in the hollow shell;

the rear end face of the pressure head is coaxially connected with the front end face of the hollow shell in a limiting contact manner and is fixedly connected with the front end face of the valve body; the front part of the switching sleeve is fixedly connected with the rear end face of the hollow shell.

2. The coal seam hydraulic pressure relief hole protecting drill according to claim 1, characterized in that: the valve body comprises a spherical valve core and a valve core control switch, the valve core control switch comprises an unlocking sleeve, an unlocking spring, a valve core fixing sleeve and an unlocking mechanism, the front end face of the valve core fixing sleeve is in limit sealing contact with the inner cavity of the hollow shell, the front end face of the valve core fixing sleeve is provided with a hollow threaded shaft, the front end face of the valve core fixing sleeve is in threaded connection with the rear end of a pressure head through the hollow threaded shaft, the unlocking spring is sleeved at the front part of the outer wall of the valve core fixing sleeve, the front end face of the unlocking spring is in limit contact with the inner cavity of the hollow shell, the upper end and the lower end of the valve core are respectively provided with a valve rod, and the valve core is arranged in the valve core fixing sleeve and is in rotary connection with the valve core fixing sleeve through the valve rods at the two ends; two valve rods of the valve core respectively extend outwards and are provided with concentric gears; the unlocking sleeve is partially sleeved at the rear part of the outer wall of the valve core fixing sleeve, a water passing gap is formed between the outer wall of the unlocking sleeve and the inner wall of the hollow shell, and the middle part of the hollow shell is provided with a low-pressure water passing through hole communicated with the inner wall and the outer wall; two long grooves are formed in the outer wall of the front part of the unlocking sleeve, gears on two valve rods of the valve core are respectively and correspondingly arranged in one long groove, and a straight rack meshed with the gears is respectively and fixedly arranged on the side wall of one side of each of the two long grooves; the rear end face of the unlocking spring is in contact connection with the front end face of the unlocking sleeve;

the unlocking mechanism comprises a plurality of long holes which are uniformly distributed on the circumferential direction of the side wall of the front part of the unlocking sleeve, and locking plates, pin shafts and torsional springs, wherein the number of the locking plates corresponds to that of the long holes; an annular groove is formed in the inner wall of the rear part of the hollow shell;

in an initial state, the unlocking spring is in a compressed state, the outer ends of the locking plates are abutted against the inner wall of the annular groove of the hollow shell under the action of the torsion spring, the valve core is in a closed state, and the diameter of a circular area defined by the inner end faces of the locking plates is smaller than the outer diameter of the sieve tube; under the open mode, the unblock spring resets, and the spur rack in the unblock sleeve drives the gear rotation on the case, and then drives the case and opens, and the outer end of locking plate is contradicted on the inner wall of cavity casing, and the circular regional diameter more than or equal to screen pipe external diameter that the inner terminal surface of a plurality of locking plates encloses.

3. The coal seam hydraulic pressure relief hole protecting drill according to claim 1, characterized in that: the inner joint is provided with an inner conical thread section in threaded connection with the hollow drill rod; the outer joint is provided with an outer cone thread section connected with the drill bit thread.

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