Coal mine crossing drilling pressure relief blowout prevention drilling, punching and protecting integrated construction method

Abstract

The invention discloses a coal mine crossing drilling pressure relief blowout prevention drilling, punching and protecting integrated construction method which comprises the following steps: firstly, moving a drilling machine to a drilling position, fixing the drilling machine, and sequentially mounting a prismatic sieve pore drill rod, an open-close sieve pore drill bit and a flow supply slag discharging device on the drilling machine; then, the construction angle of the drilling machine is adjusted, low-pressure water flow or pressure air flow is provided for the prismatic sieve hole drill rod and the open-close type sieve hole drill bit through the water supply slag discharging device, and the drilling machine is started to drive the open-close type sieve hole drill bit to conduct drilling; after drilling to a designated position, high-pressure water flow is provided for the prismatic sieve pore drill rod and the open-close sieve pore drill bit through the water supply slag discharging device for punching operation; and after punching is completed, the hole protecting device is conveyed to the bottom of the drill hole through the flow supply slag discharging device, the prismatic sieve hole drill rod and the opening and closing type sieve hole drill bit, so that the hole protecting device is clamped on the wall of the drill hole to achieve hole protection. The hole protection device can conveniently enter the drill hole to carry out lower screen pipe hole protection on the coal seam section of the layer-penetrating drill hole, the service period of the drill hole is prolonged, and then the gas extraction rate is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of underground drilling in coal mines, and in particular relates to an integrated construction method for coal mine through-layer drilling, pressure relief, blowout prevention, drilling and impact protection. Background Art

[0002] Pre-extraction of gas from coal seams by drilling is a common measure for preventing coal and gas outburst accidents in high-gas and outburst mines. Gas extraction can effectively reduce the gas content and gas pressure of coal seams. However, when drilling in soft outburst coal seams or coal seam sections of through-layer drilling, due to the influence of factors such as ground stress, gas pressure, and drilling tool disturbance, the drilling is prone to abnormal phenomena such as hole collapse, hole blockage, hole spraying, and drill sticking. This not only limits the drilling depth of the borehole, but may also cause the gas in the spray hole to exceed the limit, posing serious safety hazards to on-site construction.

[0003] At present, the coal mining industry mainly adopts the method of installing blowout prevention devices outside the borehole for borehole blowout prevention. These methods are passive technical measures after the borehole blowout occurs, and they cannot actively prevent blowout from the inside of the borehole, especially it is difficult to completely solve the common blowout problem caused by borehole blockage. During the drilling process, once the borehole is blocked, the gas deep in the borehole will gradually accumulate to form a "gas bag" with a certain pressure and volume. When the blocked section of the borehole is suddenly unblocked by forcibly pushing, pulling and twisting the drill rod, the high-pressure gas accumulated inside the borehole will suddenly spray out from the borehole, causing the orifice and tunnel gas to exceed the limit, which will cause a gas safety accident in severe cases. Therefore, it is urgent to develop a coal mine through-layer drilling pressure relief and blowout prevention integrated construction method that has a pressure relief and blowout prevention function, low drilling resistance, and can meet the needs of safe and efficient drilling of soft and protruding coal seams. Summary of the invention

[0004] The purpose of the present invention is to provide a coal mine through-layer drilling pressure relief and blowout prevention integrated construction method, which has a pressure relief and blowout prevention function, has low drilling resistance, and can meet the needs of safe and efficient drilling in soft and protruding coal seams. When the present application performs upward drilling in a coal (rock) layer, a part of the drill slag in the borehole is discharged outward through the gap between the open-and-closed sieve hole drill bit, the prismatic sieve hole drill rod and the inner wall of the borehole, and the other part enters the first channel and the second channel of the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first slag inlet hole and the second slag inlet hole. The drill slag that enters is discharged outward along the first channel, the second channel and the third channel under the joint action of fluid and gravity. The rotation of the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit will reduce the resistance between the drill slag and the wall of the channel, accelerate the sliding speed, and thus improve the slag discharge efficiency. In addition, the gas deep in the borehole of the present invention can enter the channel through the second slag inlet hole of the open-and-closed sieve hole drill bit and the first slag inlet hole of the prismatic sieve hole drill rod, and then connect with the outside of the borehole, avoiding gas accumulation inside the borehole, and effectively solving the technical problems of abnormal gas gushing out of the hole causing spray holes and spray holes caused by blockage due to borehole collapse.

[0005] To achieve the above object, the present invention adopts the following technical solution: A coal mine through-layer drilling pressure relief blowout prevention drilling and impact protection integrated construction method comprises the following steps: (1) Move the drilling rig to the drilling position, fix the drilling rig, and install the prismatic sieve hole drill rod, the open and closed sieve hole drill bit and the slag supply and discharge device on the drilling rig in sequence; (2) Adjust the drilling rig construction angle, provide low-pressure water flow or pressure air flow to the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the slag supply device, start the drilling rig to drive the open-and-closed sieve hole drill bit to drill; (3) After reaching the designated position, high-pressure water flow is supplied to the prism-shaped screen hole drill rod and the open-and-closed screen hole drill bit through the flow discharger to perform punching operations; (4) After the punching is completed, the hole protection device is sent to the bottom of the borehole through the slag discharge device, the prismatic sieve drill rod and the open-close sieve drill bit, so that the hole protection device is stuck on the borehole wall to protect the hole.

[0006] The prismatic sieve hole drill rod comprises a drill rod body, the interior of the drill rod body is provided with a first passage which is through front and back and has a circular cross section, the drill rod body comprises a first cylinder at the rear end, a first prism in the middle and a second cylinder at the front end, the front end of the second cylinder is provided with a first threaded joint, the first threaded joint comprises a first threaded section and a first extension section, the outer diameter of the first threaded section is smaller than the outer diameter of the drill rod body, the outer diameter of the first extension section is smaller than the outer diameter of the first threaded section, the outer surface of the first threaded section is provided with a first male thread, the interior of the rear end of the first cylinder is provided with a first female thread, and a first axial groove is provided between adjacent side surfaces of the first prism along the front and rear direction of the prism; The flow discharger includes a rotating tube, the interior of which is arranged as a third channel which is through from front to back and has a circular cross section, an external shell is sleeved on the rotating tube, an annular flow supply chamber is formed between the external shell and the rotating tube, the external shell is provided with a cylindrical portion extending outward along the annular flow supply chamber, the center of the cylindrical portion is arranged as a first flow supply channel which is through from top to bottom, the first flow supply channel is connected with the annular flow supply chamber, a second threaded joint is arranged at the front end of the rotating tube, the second threaded joint includes a second threaded section and a second extension section, the outer diameter of the second threaded section is smaller than the outer diameter of the rotating tube, the outer diameter of the second extension section is smaller than the outer diameter of the second threaded section, a second male thread is arranged on the outer surface of the second threaded section, the flow discharger is installed on the rear end of the prismatic sieve hole drill rod at the rear end by threaded cooperation of the second male thread and the first female thread; a plurality of first arc-shaped grooves arranged along the front-to-back direction are arranged on the outer circumference of the first threaded section, and a plurality of second arc-shaped grooves arranged along the front-to-back direction are arranged on the outer circumference of the second threaded section.

[0007] The first axial groove and the second axial groove are both covered with a thin-walled cover plate, so that the interior of the first axial groove and the second axial groove is set as a closed cavity to form a second fluid supply channel, a first oblique fluid supply channel is arranged between the inner wall and the outer wall of the first cylinder, the first oblique fluid supply channel is higher at the front and lower at the back, the rear end of the first oblique fluid supply channel is connected to the first channel, the front end of the first oblique fluid supply channel is connected to the rear end of the second fluid supply channel in the first axial groove, a second oblique fluid supply channel is arranged between the inner wall and the outer wall of the second cylinder, the second oblique fluid supply channel passes through the front end surface of the second cylinder and its extension line is located in the first arc-shaped groove, and the rear end of the second oblique fluid supply channel is connected to the front end of the second fluid supply channel in the first axial groove.

[0008] A thin-walled fluid supply tube is provided in each of the first axial groove and the second axial groove, and the interior of the thin-walled fluid supply tube is provided as a second fluid supply channel, a first oblique fluid supply channel is provided between the inner wall and the outer wall of the first cylinder, the first oblique fluid supply channel is higher at the front and lower at the back, the rear end of the first oblique fluid supply channel is connected to the first channel, the front end of the first oblique fluid supply channel is connected to the rear end of the second fluid supply channel in the first axial groove, a second oblique fluid supply channel is provided between the inner wall and the outer wall of the second cylinder, the second oblique fluid supply channel is higher at the front and lower at the back, the second oblique fluid supply channel passes through the front end surface of the second cylinder and its extension line is located in the first arc-shaped groove, and the rear end of the second oblique fluid supply channel is connected to the front end of the second fluid supply channel in the first axial groove.

[0009] The open-and-closed sieve hole drill bit includes a drill shank, the interior of the drill shank is arranged as a second channel which runs through from front to back and has a circular cross section, the second channel is connected to the first channel, the drill shank includes a third cylinder at the rear end and a second prism at the front end, a plurality of cutting edges are evenly arranged at the front end of the second prism along the circumferential direction, a second female thread corresponding to the first male thread is arranged at the rear end of the third cylinder, the open-and-closed sieve hole drill bit is installed on the front end of the front-end prismatic sieve hole drill rod through the threaded cooperation of the first male thread and the second female thread, a rotating stopper is arranged at the front end center of the second prism, and a second axial groove is arranged between adjacent side surfaces of the second prism along the front-to-back direction of the prism.

[0010] A third oblique flow supply channel is arranged between the inner wall and the outer wall of the third cylinder, the third oblique flow supply channel is higher at the front and lower at the rear, the rear end of the third oblique flow supply channel is connected to the second channel, the front end of the third oblique channel is connected to the rear end of the second flow supply channel in the second axial groove, a punching nozzle and a connecting channel are arranged on the cutting edge, the front end of the connecting channel is connected to the punching nozzle, the rear end of the connecting channel is connected to the front end of the second flow supply channel in the second axial groove, a cutting blade is arranged on the rotating stopper, the rotating stopper is hinged at the right end of the rotating tube, and the rotating stopper will flip forward under the action of a large thrust, so that the second channel of the open-and-closed sieve hole drill bit is completely unblocked; Spiral grooves are arranged on the first prism and the second prism along the first axial groove and the second axial groove; a plurality of first slag inlet holes connected to the first channel are arranged on the side surface of the first prism, and a plurality of second slag inlet holes connected to the second channel are arranged on the side surface of the second prism; an axial flow supply channel is arranged between the inner wall and the outer wall of the rotating tube, and the axial flow supply channel passes through the front end surface of the rotating tube and its extension line is located in the second arc-shaped groove.

[0011] The hole protection device includes a hanging head and a screen tube. The screen tube is a detachable screen tube. Several screen tubes connected together are connected to the rear end of the hanging head. The front end of the hanging head is arranged as a conical structure. An ejection mechanism is arranged inside the hanging head. The ejection mechanism includes symmetrically arranged claws and springs. A through hole corresponding to the claws is arranged on the surface of the hanging head.

[0012] The specific process of step (2) is as follows: low-pressure water or pressure air flow is injected into the supply and discharge device, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first supply channel of the cylindrical portion; the low-pressure water or pressure air flow enters the annular supply chamber through the first supply channel, and then flows into the first inclined supply channel of the prismatic sieve hole drill rod through the axial supply channel, and then flows into the second supply channel of the prismatic sieve hole drill rod, and then enters the third inclined supply channel of the open-and-closed sieve hole drill bit through the second inclined supply channel, and then flows into the second supply channel of the open-and-closed sieve hole drill bit, and finally enters the borehole through the punching nozzle, so that part of the drill cuttings and gas in the borehole is discharged outward through the gap between the supply and discharge device, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit and the inner wall of the borehole, and the other part enters the first channel and the second channel through the first slag inlet hole and the second slag inlet hole, and then is discharged from the hole under the action of gravity.

[0013] The specific operation process of step (3) is as follows: high-pressure water is injected into the flow discharger, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first flow supply channel of the cylindrical portion; the high-pressure water enters the annular flow supply cavity through the first flow supply channel, and then flows into the first inclined flow supply channel of the prismatic sieve hole drill rod through the axial flow supply channel, and then flows into the second flow supply channel of the prismatic sieve hole drill rod, and then enters the third inclined flow supply channel of the open-and-closed sieve hole drill bit through the second inclined flow supply channel, and then flows into the second flow supply channel of the open-and-closed sieve hole drill bit, and finally is ejected through the punching nozzle, and the ejected high-pressure water flow punches the coal hole section of the through-layer drilling hole.

[0014] The specific process of step (4) is as follows: after the punching is completed, the hole protection device is sent to the bottom of the borehole through the third channel, the first channel and the second channel. During the sending process, it will be blocked by the rotating block in the second channel, and a thrust is applied to the hole protection device. The rotating block rotates forward under the action of the thrust, and the second channel is opened. The hole protection device enters the borehole. After the hole protection device enters the borehole, the claw in the suspension head pops out through the through hole under the action of the spring and is stuck on the borehole wall. Finally, the slag discharger, the prismatic sieve hole drill rod and the open and close sieve hole drill bit are withdrawn, and the hole protection device remains in the borehole for gas extraction.

[0015] The cutting edge of the present application is equipped with a radial punching nozzle, which can be used for slag removal during low-pressure drilling, and can be punched when high-pressure water is injected. The permeability of the coal seam can be effectively improved by punching the coal seam section, and the gas extraction effect can be further improved. In addition, the open-closed screen hole drill bit and the prism-shaped screen hole drill rod of the present invention both have the function of slag inlet pressure relief, which can greatly reduce the rotational resistance of the drill rod body and the drill handle. Under the condition of a certain torque of the drilling rig, the drilling depth of the soft coal seam drilling is greatly improved, thereby ensuring a good drilling gas extraction effect.

[0016] The gas deep in the borehole of the present invention can enter the second channel and the first channel through the second slag inlet hole of the open-and-closed screen hole drill bit and the first slag inlet hole of the prismatic screen hole drill rod, and directly connect to the outside of the borehole through the third channel of the slag outlet, so as to avoid the accumulation of high-pressure gas inside the borehole, thereby playing the role of pressure relief and blowout prevention, and effectively solving the technical problems of the blowhole caused by abnormal gas outflow in the hole and the blowhole caused by the collapse and blockage of the borehole. In addition, the diameters of the first channel, the second channel and the third channel of the present invention are consistent, and there is no diameter change, which facilitates the hole protection device to enter the borehole to protect the lower screen pipe hole of the coal seam section of the through-layer drilling, thereby improving the service cycle of the borehole and thereby improving the gas extraction rate.

[0017] To summarize, when the present application performs uphole drilling in a coal (rock) layer, a portion of the drill cuttings in the borehole will be discharged outward through the gap between the open-and-closed sieve hole drill bit, the prismatic sieve hole drill rod and the inner wall of the borehole, and the other portion will enter the first channel and the second channel of the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first slag inlet hole and the second slag inlet hole. The entered drill cuttings will be discharged outward along the first channel, the second channel and the third channel under the combined action of fluid and gravity. The rotation of the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit will reduce the resistance between the drill cuttings and the channel wall, accelerate the sliding speed, and thereby improve the slag discharge efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The invention is a schematic structural diagram of a slag discharge device, a prismatic sieve hole drill rod and an open-and-closed sieve hole drill bit.

[0019] Figure 2 It is one of the structural schematic diagrams of the prismatic sieve hole drill rod of the present invention.

[0020] Figure 3 This is the second structural schematic diagram of the prismatic sieve hole drill rod of the present invention.

[0021] Figure 4 It is a schematic diagram of the internal structure of the prismatic sieve hole drill rod of the present invention.

[0022] Figure 5 The present invention is a schematic structural diagram of a prismatic sieve hole drill rod with spiral grooves.

[0023] Figure 6 It is a schematic diagram of the structure of the arc-shaped groove and the axial groove of the present invention as an arc-shaped groove.

[0024] Figure 7 It is a schematic structural diagram of the arc groove and the axial groove of the present invention being inverted trapezoidal grooves.

[0025] Figure 8 It is a structural schematic diagram of the arc-shaped groove and the axial groove of the present invention as arc bottom grooves.

[0026] Fig. 9It is a schematic structural diagram of the thin-walled cover plate and the second flow supply channel of the present invention.

[0027] Fig.10 It is a schematic structural diagram of the threaded connection between the prismatic sieve hole drill rods of the present invention.

[0028] Fig.11 It is a structural schematic diagram of the open-and-closed screen hole drill bit of the present invention.

[0029] Fig.12 It is a schematic diagram of the internal structure of the open-and-closed screen hole drill bit of the present invention.

[0030] Fig.13 It is a schematic structural diagram of the closing of the rotary stopper of the open-and-closed screen hole drill bit of the present invention.

[0031] Fig.14 It is a structural schematic diagram of the open and close type screen hole drill bit of the present invention with the rotary stopper opened.

[0032] Fig.15 It is a structural schematic diagram of the slag supply and discharge device of the present invention.

[0033] Fig.16 It is a schematic diagram of the internal structure of the slag supply and discharge device of the present invention.

[0034] Fig.17 It is a schematic structural diagram of the closed claws of the hole protection device of the present invention.

[0035] Fig.18 It is a schematic structural diagram of the hole protection device of the present invention when the claws are opened.

[0036] Fig.19 It is a structural schematic diagram of another embodiment of the first threaded joint of the present invention.

[0037] Fig. 20 It is a cross-sectional view of another embodiment of the first threaded joint of the present invention. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are further described below with reference to the accompanying drawings.

[0039] Embodiment 1 like Figure 1-18 As shown, a coal mine through-layer drilling pressure relief blowout prevention drilling and impact protection integrated construction method comprises the following steps: (1) Move the drilling rig to the drilling position, fix the drilling rig, and install the prismatic sieve hole drill rod 2, the open-closed sieve hole drill bit 3 and the slag discharger 1 on the drilling rig in sequence; (2) adjusting the drilling rig construction angle, providing low-pressure water flow or pressure air flow to the prismatic sieve hole drill rod 2 and the open-and-closed sieve hole drill bit 3 through the supply and discharge device 1, and starting the drilling rig to drive the open-and-closed sieve hole drill bit 3 to drill; (3) After reaching the designated position, high-pressure water flow is supplied to the prismatic sieve drill rod 2 and the open-and-closed sieve drill bit 3 through the flow discharger 1 to perform punching operations; (4) After the punching is completed, the hole protection device is sent to the bottom of the borehole through the slag supply device 1, the prismatic sieve hole drill rod 2 and the open-close sieve hole drill bit 3, so that the hole protection device is clamped on the borehole wall to protect the hole.

[0040] The prismatic sieve hole drill rod 2 includes a drill rod body 4, the interior of the drill rod body 4 is provided with a first channel 5 which is through from front to back and has a circular cross section, the drill rod body 4 includes a first cylinder 11 at the rear end, a first prism 12 in the middle and a second cylinder 17 at the front end, a first threaded joint 6 is provided at the front end of the second cylinder 17, the first threaded joint 6 includes a first threaded section 7 and a first extension section 8, the outer diameter of the first threaded section 7 is smaller than the outer diameter of the drill rod body 4, the outer diameter of the first extension section 8 is smaller than the outer diameter of the first threaded section 7, and the outer diameter of the first threaded section 7 is provided outside There are a plurality of first arc grooves 9 arranged along the front-to-back direction, the outer surface of the first threaded section 7 is provided with a first male thread 10, the front end outer surface of the first extension section 8 is provided with an annular groove, and a sealing ring 51 is installed in the annular groove for achieving high-pressure sealing to prevent the fluid from leaking from the gap in advance, thereby affecting the normal drilling, deslagging or high-pressure punching operation of the front-end open-and-closed screen drill 3; a first female thread 48 is arranged inside the rear end of the first cylinder 11, and a first axial groove 46 is arranged between adjacent side surfaces of the first prism 12 along the front-to-back direction of the prism; The flow discharger 1 includes a rotating tube 19, the interior of the rotating tube 19 is provided with a third channel 20 which is through front and back and has a circular cross section, an outer shell 21 is sleeved on the rotating tube 19, an annular flow supply cavity 22 is formed between the outer shell 21 and the rotating tube 19, the outer shell 21 is provided with a cylindrical portion 23 extending outward along the annular flow supply cavity 22, the center of the cylindrical portion 23 is provided with a first flow supply channel 24 which is through from top to bottom, the first flow supply channel 24 is connected to the annular flow supply cavity 22, and a second threaded joint 2 is provided at the front end of the rotating tube 19 5. The second threaded joint 25 includes a second threaded section 26 and a second extension section 27. The outer diameter of the second threaded section 26 is smaller than the outer diameter of the rotating tube 19. The outer diameter of the second extension section 27 is smaller than the outer diameter of the second threaded section 26. The outer portion of the second threaded section 26 is provided with a plurality of second arc-shaped grooves 28 arranged along the front-to-back direction. The outer surface of the second threaded section 26 is provided with a second male thread 29. The slag supply device 1 is installed on the rear end of the rearmost prismatic sieve hole drill rod 2 through the threaded cooperation of the second male thread 29 and the first female thread 48.

[0041] The first axial groove 46 and the second axial groove 47 are both covered with a thin-walled cover plate 45, so that the interior of the first axial groove 46 and the second axial groove 47 is set as a closed cavity to form a second supply channel 31, and a first oblique supply channel 32 is arranged between the inner wall and the outer wall of the first cylinder 11. The first oblique supply channel 32 is higher at the front and lower at the back, and the rear end of the first oblique supply channel 32 is connected to the first channel 5, and the front end of the first oblique supply channel 32 is connected to the rear end of the second supply channel 31 in the first axial groove 46. A second oblique supply channel 33 is arranged between the inner wall and the outer wall of the second cylinder 17, and the second oblique supply channel 33 passes through the front end surface of the second cylinder 17 and its extension line is located in the first arc-shaped groove 9, and the rear end of the second oblique supply channel 33 is connected to the front end of the second supply channel 31 in the first axial groove 46. When the wall thickness of the prismatic sieve drill rod body 4 is relatively thick, in order to facilitate the construction of the first oblique flow supply channel 32 and the second oblique flow supply channel 33, the first oblique flow supply channel 32 and the second oblique flow supply channel 33 can be arranged in parallel along the axial direction of the drill rod body 4, and the oblique flow supply channel becomes a parallel axial flow supply channel. In addition, in order to meet the requirements of the actual drilling construction site for the strength and flow flow of the prismatic sieve drill rod, the cross-sectional shape of the first oblique flow supply channel 32 and the second oblique flow supply channel 33 can be a circular hole, a waist-shaped hole or an elliptical hole, and the number of the first oblique flow supply channel 32 at the first cylinder 11 and the second oblique flow supply channel 33 at the second cylinder 17 can be one or more.

[0042] Since the first threaded section 7 of the prismatic sieve hole drill rod 2 is an incomplete thread, two adjacent prismatic sieve hole drill rods 2 are threadedly connected to form a plurality of branch flow supply channels 49 in the threaded connection section; in order to solve the problem of blocking the flow supply when the first oblique flow supply channel 32 and the second oblique flow supply channel 33 of two adjacent prismatic sieve hole drill rods 2 are not aligned, an annular transition chamber 50 is provided at the threaded connection, and the fluid first enters the branch flow supply channel 49 from the first oblique flow supply channel 32, and then after passing through the annular transition chamber 50, it can enter the second flow supply channel 31 of the next drill rod from the second oblique flow supply channel 33, and then be supplied to the open and closed type sieve hole drill bit 3.

[0043] In addition, the first arc groove 9, the second arc groove 28, the first axial groove 46 and the second axial groove 47 can be Figure 6 The arc groove structure shown can also be Figure 7 The inverted trapezoidal groove structure shown in FIG. Figure 8 The arc bottom groove structure shown in the figure can be selected and appropriately optimized according to the construction conditions for the strength of the prismatic sieve hole drill rod 2 and the requirements for the flow rate.

[0044] The open-and-closed sieve hole drill bit 3 includes a drill shank 13, the interior of the drill shank 13 is arranged as a second channel 14 which passes through from front to back and has a circular cross section, the second channel 14 is connected to the first channel 5, the drill shank 13 includes a third cylinder 40 at the rear end and a second prism 39 at the front end, a plurality of cutting edges 15 are evenly arranged at the front end of the second prism 39 along the circumferential direction, a second female thread 16 corresponding to the first male thread 10 is arranged at the rear end of the third cylinder 40, the open-and-closed sieve hole drill bit 3 is installed on the front end of the frontmost prismatic sieve hole drill rod 2 by threaded cooperation of the first male thread 10 and the second female thread 16, a rotating stopper 18 is arranged at the front end center of the second prism 39, and a second axial groove 47 is arranged between adjacent side surfaces of the second prism 39 along the front and rear direction of the prism.

[0045] A third oblique flow supply channel 34 is arranged between the inner wall and the outer wall of the third cylinder 40. The third oblique flow supply channel 34 is higher at the front and lower at the back. The rear end of the third oblique flow supply channel 34 is connected to the second channel 14. The front end of the third oblique channel is connected to the rear end of the second flow supply channel 31 in the second axial groove 47. A punching nozzle 37 and a connecting channel are arranged on the cutting edge 15. The front end of the connecting channel is connected to the punching nozzle 37. The rear end of the connecting channel is connected to the front end of the second flow supply channel 31 in the second axial groove 47. A cutting blade is arranged on the rotating stopper 18. The rotating stopper 18 is hinged at the right end of the rotating tube 19. Under the action of a large thrust, the rotating stopper 18 will flip forward to make the second channel 14 of the open-closed sieve hole drill 3 completely unblocked. Spiral grooves 30 are provided along the first axial grooves 46 and the second axial grooves 47 on the first prism 12 and the second prism 39; a plurality of first slag inlet holes 35 connected to the first channel 5 are provided on the side surface of the first prism 12, and a plurality of second slag inlet holes 36 connected to the second channel 14 are provided on the side surface of the second prism 39; an axial flow supply channel 38 is provided between the inner wall and the outer wall of the rotating tube 19, and the axial flow supply channel 38 passes through the front end surface of the rotating tube 19 and its extension line is located in the second arc-shaped groove 28.

[0046] The hole protection device includes a hanging head 41 and a screen tube 42. The screen tube 42 is a detachable screen tube 42. Several screen tubes 42 connected together are connected to the rear end of the hanging head 41. The front end of the hanging head 41 is set as a conical structure. The interior of the hanging head 41 is provided with an ejection mechanism. The ejection mechanism includes symmetrically arranged claws 43 and a spring. The surface of the hanging head 41 is provided with through holes corresponding to the claws 43.

[0047] The specific process of step (2) is as follows: low-pressure water or pressure airflow is injected into the supply and discharge slag device 1, the prism-shaped sieve hole drill rod 2 and the open-closed sieve hole drill bit 3 through the first supply channel 24 of the cylindrical portion 23, and the low-pressure water or pressure airflow enters the annular supply cavity 22 through the first supply channel 24, and then flows into the first oblique supply channel 32 of the prism-shaped sieve hole drill rod 2 through the axial supply channel 38, and then flows into the second supply channel 31 of the prism-shaped sieve hole drill rod 2, and then enters through the second oblique supply channel 33. The gas flows into the third inclined flow supply channel 34 of the open-and-closed sieve hole drill bit 3, and then flows into the second flow supply channel 31 of the open-and-closed sieve hole drill bit 3, and finally enters the borehole through the punching nozzle 37, so that part of the drill cuttings and gas in the borehole is discharged outward through the gap between the supply and discharge device 1, the prismatic sieve hole drill rod 2 and the open-and-closed sieve hole drill bit 3 and the inner wall of the borehole, and the other part enters the first channel 5 and the second channel 14 through the first slag inlet hole 35 and the second slag inlet hole 36, and then is discharged from the hole under the action of gravity.

[0048] The specific operation process of step (3) is as follows: high-pressure water is injected into the supply slag discharger 1, the prismatic sieve hole drill rod 2 and the open-and-closed sieve hole drill bit 3 through the first supply channel 24 of the cylindrical portion 23; the high-pressure water enters the annular supply chamber 22 through the first supply channel 24, and then flows into the first inclined supply channel 32 of the prismatic sieve hole drill rod 2 through the axial supply channel 38, and then flows into the second supply channel 31 of the prismatic sieve hole drill rod 2, and then enters the third inclined supply channel 34 of the open-and-closed sieve hole drill bit 3 through the second inclined supply channel 33, and then flows into the second supply channel 31 of the open-and-closed sieve hole drill bit 3, and finally is ejected through the punching nozzle 37, and the ejected high-pressure water flow punches the coal hole section of the through-layer drilling hole.

[0049] The specific process of step (4) is as follows: after punching is completed, the hole protection device is sent to the bottom of the borehole through the third channel 20, the first channel 5 and the second channel 14. During the sending process, it will be blocked by the rotating block 18 in the second channel 14, and a thrust is applied to the hole protection device. The rotating block 18 rotates forward under the action of the thrust, and the second channel 14 is opened. The hole protection device enters the borehole. After the hole protection device enters the borehole, the claw 43 in the hanging head 41 pops out through the through hole under the action of the spring and is stuck on the borehole wall. Finally, the slag supply device 1, the prismatic sieve hole drill rod 2 and the open and close sieve hole drill bit 3 are withdrawn, and the hole protection device remains in the borehole for gas extraction.

[0050] The cutting edge 15 of the present application is equipped with a radial punching nozzle 37, which can be used for slag removal during low-pressure drilling, and can be punched when high-pressure water is injected. The permeability of the coal seam can be effectively improved by punching the coal seam section, and the gas extraction effect can be further improved. In addition, the open-closed screen hole drill bit 3 and the prism-shaped screen hole drill rod 2 of the present invention both have the function of slag inlet pressure relief, which can greatly reduce the rotational resistance of the drill rod body 4 and the drill handle 13. Under the condition of a certain torque of the drilling rig, the drilling depth of the soft coal seam drilling is greatly improved, thereby ensuring a good drilling gas extraction effect. The gas deep in the borehole of the present invention can enter the second channel 14 and the first channel 5 through the second slag inlet hole 36 of the open-and-closed screen hole drill bit 3 and the first slag inlet hole 35 of the prismatic screen hole drill rod 2, and directly connect to the outside of the borehole through the third channel 20 of the slag outlet 1, so as to avoid the accumulation of high-pressure gas inside the borehole, thereby playing the role of pressure relief and blowout prevention, and effectively solving the technical problems of abnormal gas outflow in the hole leading to the blowhole and the blowhole caused by the collapse and blockage of the borehole. In addition, the diameters of the first channel 5, the second channel 14 and the third channel 20 of the present invention are consistent, and there is no diameter change, which facilitates the hole protection device to enter the borehole to protect the lower screen pipe 42 of the coal seam section of the through-layer drilling, thereby improving the service cycle of the borehole and thus improving the gas extraction rate. When the present application performs uphole drilling in a coal (rock) layer, a portion of the drill cuttings in the borehole is discharged outward through the gap between the open-and-closed sieve hole drill bit 3 and the prismatic sieve hole drill rod 2 and the inner wall of the borehole, and the other portion enters the first channel 5 and the second channel 14 of the prismatic sieve hole drill rod 2 and the open-and-closed sieve hole drill bit 3 through the first slag inlet hole 35 and the second slag inlet hole 36. The entered drill cuttings are discharged outward along the first channel 5, the second channel 14 and the third channel 20 under the combined action of fluid and gravity. The rotation of the prismatic sieve hole drill rod 2 and the open-and-closed sieve hole drill bit 3 reduces the resistance between the drill cuttings and the channel wall, accelerates the sliding speed, and thereby improves the slag discharge efficiency.

[0051] Embodiment 2 What is different from the first embodiment is that a thin-walled fluid supply tube is provided in the first axial groove 46 and the second axial groove 47, and the interior of the thin-walled fluid supply tube is provided as a second fluid supply channel 31, that is, the thin-walled fluid supply tube replaces the closed cavity structure formed by the thin-walled cover plate 45 and the first axial groove 46 and the second axial groove 47.

[0052] Embodiment 3 The differences from the first embodiment are as follows: Fig.19 and Fig. 20As shown, in the use scenario where deep hole drilling is required, the prism-shaped screen hole spiral drill rod 2 should have higher strength. Therefore, in order to improve the strength of the first threaded section 7 (male thread) at the front end of the drill rod body, the first arc groove 9 may not be provided on the surface of the first threaded section 7, but an axial flow supply hole may be provided in the wall thickness of the first threaded section 7, and the axial flow supply hole is connected to the second oblique flow supply channel 33. In this way, the first threaded section 7 is a complete threaded structure, and the strength of the threaded connection structure of the drill rod is improved.

[0053] In addition, the inner hole of the drill rod body 4 of the prismatic sieve hole drill rod 2 can also be an unequal diameter structure, that is, the wall thickness at the first threaded joint 6 and the first cylinder 11 is increased inwardly, and correspondingly, the inner hole diameter at the first threaded joint 6 and the first cylinder 11 becomes smaller, which can also improve the strength of the prismatic sieve hole drill rod 2.

[0054] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A coal mine through-layer drilling pressure relief blowout prevention drilling and impact protection integrated construction method, characterized in that: The steps include: (1) Move the drilling rig to the drilling position, fix the drilling rig, and install the prismatic sieve hole drill rod, the open and closed sieve hole drill bit and the slag supply and discharge device on the drilling rig in sequence; (2) Adjust the drilling rig construction angle, provide low-pressure water flow or pressure air flow to the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the slag supply device, start the drilling rig to drive the open-and-closed sieve hole drill bit to drill; (3) After reaching the designated position, high-pressure water flow is supplied to the prism-shaped screen hole drill rod and the open-and-closed screen hole drill bit through the flow discharger to perform punching operations; (4) After the punching is completed, the hole protection device is sent to the bottom of the borehole through the slag discharge device, the prismatic sieve drill rod and the open-close sieve drill bit, so that the hole protection device is stuck on the borehole wall to protect the hole.

2. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 1 is characterized by: The prismatic sieve hole drill rod comprises a drill rod body, the interior of the drill rod body is provided with a first passage which is through front and back and has a circular cross section, the drill rod body comprises a first cylinder at the rear end, a first prism in the middle and a second cylinder at the front end, the front end of the second cylinder is provided with a first threaded joint, the first threaded joint comprises a first threaded section and a first extension section, the outer diameter of the first threaded section is smaller than the outer diameter of the drill rod body, the outer diameter of the first extension section is smaller than the outer diameter of the first threaded section, the outer surface of the first threaded section is provided with a first male thread, the interior of the rear end of the first cylinder is provided with a first female thread, and a first axial groove is provided between adjacent side surfaces of the first prism along the front and rear direction of the prism; The flow discharger includes a rotating tube, the interior of which is arranged as a third channel which is through from front to back and has a circular cross section, an external shell is sleeved on the rotating tube, an annular flow supply chamber is formed between the external shell and the rotating tube, the external shell is provided with a cylindrical portion extending outward along the annular flow supply chamber, the center of the cylindrical portion is arranged as a first flow supply channel which is through from top to bottom, the first flow supply channel is connected with the annular flow supply chamber, a second threaded joint is arranged at the front end of the rotating tube, the second threaded joint includes a second threaded section and a second extension section, the outer diameter of the second threaded section is smaller than the outer diameter of the rotating tube, the outer diameter of the second extension section is smaller than the outer diameter of the second threaded section, a second male thread is arranged on the outer surface of the second threaded section, the flow discharger is installed on the rear end of the prismatic sieve hole drill rod at the rear end by threaded cooperation of the second male thread and the first female thread; a plurality of first arc-shaped grooves arranged along the front-to-back direction are arranged on the outer circumference of the first threaded section, and a plurality of second arc-shaped grooves arranged along the front-to-back direction are arranged on the outer circumference of the second threaded section.

3. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 2 is characterized by: The first axial groove and the second axial groove are both covered with a thin-walled cover plate, so that the interior of the first axial groove and the second axial groove is set as a closed cavity to form a second fluid supply channel, a first oblique fluid supply channel is arranged between the inner wall and the outer wall of the first cylinder, the first oblique fluid supply channel is higher at the front and lower at the back, the rear end of the first oblique fluid supply channel is connected to the first channel, the front end of the first oblique fluid supply channel is connected to the rear end of the second fluid supply channel in the first axial groove, a second oblique fluid supply channel is arranged between the inner wall and the outer wall of the second cylinder, the second oblique fluid supply channel passes through the front end surface of the second cylinder and its extension line is located in the first arc-shaped groove, and the rear end of the second oblique fluid supply channel is connected to the front end of the second fluid supply channel in the first axial groove.

4. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 2 is characterized by: A thin-walled fluid supply tube is provided in each of the first axial groove and the second axial groove, and the interior of the thin-walled fluid supply tube is provided as a second fluid supply channel, a first oblique fluid supply channel is provided between the inner wall and the outer wall of the first cylinder, the first oblique fluid supply channel is higher at the front and lower at the back, the rear end of the first oblique fluid supply channel is connected to the first channel, the front end of the first oblique fluid supply channel is connected to the rear end of the second fluid supply channel in the first axial groove, a second oblique fluid supply channel is provided between the inner wall and the outer wall of the second cylinder, the second oblique fluid supply channel is higher at the front and lower at the back, the second oblique fluid supply channel passes through the front end surface of the second cylinder and its extension line is located in the first arc-shaped groove, and the rear end of the second oblique fluid supply channel is connected to the front end of the second fluid supply channel in the first axial groove.

5. A coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection integrated construction method according to claim 3 or 4, characterized in that: The open-and-closed sieve hole drill bit includes a drill shank, the interior of the drill shank is arranged as a second channel which runs through from front to back and has a circular cross section, the second channel is connected to the first channel, the drill shank includes a third cylinder at the rear end and a second prism at the front end, a plurality of cutting edges are evenly arranged at the front end of the second prism along the circumferential direction, a second female thread corresponding to the first male thread is arranged at the rear end of the third cylinder, the open-and-closed sieve hole drill bit is installed on the front end of the front-end prismatic sieve hole drill rod through the threaded cooperation of the first male thread and the second female thread, a rotating stopper is arranged at the front end center of the second prism, and a second axial groove is arranged between adjacent side surfaces of the second prism along the front-to-back direction of the prism.

6. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 5 is characterized by: A third oblique flow supply channel is arranged between the inner wall and the outer wall of the third cylinder, the third oblique flow supply channel is higher at the front and lower at the rear, the rear end of the third oblique flow supply channel is connected to the second channel, the front end of the third oblique channel is connected to the rear end of the second flow supply channel in the second axial groove, a punching nozzle and a connecting channel are arranged on the cutting edge, the front end of the connecting channel is connected to the punching nozzle, the rear end of the connecting channel is connected to the front end of the second flow supply channel in the second axial groove, a cutting blade is arranged on the rotating stopper, the rotating stopper is hinged at the right end of the rotating tube, and the rotating stopper will flip forward under the action of a large thrust, so that the second channel of the open-and-closed sieve hole drill bit is completely unblocked; Spiral grooves are arranged on the first prism and the second prism along the first axial groove and the second axial groove; a plurality of first slag inlet holes connected to the first channel are arranged on the side surface of the first prism, and a plurality of second slag inlet holes connected to the second channel are arranged on the side surface of the second prism; an axial flow supply channel is arranged between the inner wall and the outer wall of the rotating tube, and the axial flow supply channel passes through the front end surface of the rotating tube and its extension line is located in the second arc-shaped groove.

7. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 6 is characterized by: The hole protection device includes a hanging head and a screen tube. The screen tube is a detachable screen tube. Several screen tubes connected together are connected to the rear end of the hanging head. The front end of the hanging head is arranged as a conical structure. An ejection mechanism is arranged inside the hanging head. The ejection mechanism includes symmetrically arranged claws and springs. A through hole corresponding to the claws is arranged on the surface of the hanging head.

8. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 7 is characterized by: The specific process of step (2) is as follows: low-pressure water or pressure air flow is injected into the supply and discharge device, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first supply channel of the cylindrical portion; the low-pressure water or pressure air flow enters the annular supply chamber through the first supply channel, and then flows into the first inclined supply channel of the prismatic sieve hole drill rod through the axial supply channel, and then flows into the second supply channel of the prismatic sieve hole drill rod, and then enters the third inclined supply channel of the open-and-closed sieve hole drill bit through the second inclined supply channel, and then flows into the second supply channel of the open-and-closed sieve hole drill bit, and finally enters the borehole through the punching nozzle, so that part of the drill cuttings and gas in the borehole is discharged outward through the gap between the supply and discharge device, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit and the inner wall of the borehole, and the other part enters the first channel and the second channel through the first slag inlet hole and the second slag inlet hole, and then is discharged from the hole under the action of gravity.

9. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 8 is characterized by: The specific operation process of step (3) is as follows: high-pressure water is injected into the flow discharger, the prismatic sieve hole drill rod and the open-and-closed sieve hole drill bit through the first flow supply channel of the cylindrical portion; the high-pressure water enters the annular flow supply cavity through the first flow supply channel, and then flows into the first inclined flow supply channel of the prismatic sieve hole drill rod through the axial flow supply channel, and then flows into the second flow supply channel of the prismatic sieve hole drill rod, and then enters the third inclined flow supply channel of the open-and-closed sieve hole drill bit through the second inclined flow supply channel, and then flows into the second flow supply channel of the open-and-closed sieve hole drill bit, and finally is ejected through the punching nozzle, and the ejected high-pressure water flow punches the coal hole section of the through-layer drilling hole.

10. The integrated construction method for coal mine through-layer drilling pressure relief, blowout prevention, drilling and protection according to claim 9, characterized in that: The specific process of step (4) is as follows: after the punching is completed, the hole protection device is sent to the bottom of the borehole through the third channel, the first channel and the second channel. During the sending process, it will be blocked by the rotating block in the second channel, and a thrust is applied to the hole protection device. The rotating block rotates forward under the action of the thrust, and the second channel is opened. The hole protection device enters the borehole. After the hole protection device enters the borehole, the claw in the suspension head pops out through the through hole under the action of the spring and is stuck on the borehole wall. Finally, the pressure relief and blowout prevention spiral supply slag discharge device, the prismatic sieve hole drill rod and the open and close sieve hole drill bit are withdrawn from the borehole, and the hole protection device is left in the borehole for gas extraction.

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