A carbon dioxide phase change blasting-assisted chip removal device and method

Abstract

The present application provides a carbon dioxide phase change blasting assisted chip removal device and method. In this device, both ends of the spiral jet drill pipe are detachably connected to an oscillating jet drill bit and a carbon dioxide phase change pipe respectively; a plurality of oscillating jet holes are provided on the oscillating jet drill bit, spiral exhaust holes are provided on the spiral jet drill pipe, a carbon dioxide activation cavity is provided in the carbon dioxide phase change pipe, and a carbon dioxide phase change unit is provided in the carbon dioxide activation cavity. The carbon dioxide phase change unit is used to induce the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity through an activation circuit, and release the carbon dioxide converted into gas through the spiral exhaust holes and the oscillating jet holes, so that the oscillating jet drill bit and the spiral jet drill pipe generate rotational vibration, and the drill pipe itself can vibrate while dredging the drill hole, moving the drill pipe, and solving the problem of drill pipe jamming caused by hole collapse and coal powder blockage.

Description

Technical Field

[0001] This application relates to the field of mining technology, and particularly to a carbon dioxide phase change blasting assisted chip removal device and method. Background Art

[0002] Coal mine mechanical drilling is applied in many aspects of underground drilling, such as borehole blasting, stress concentration measurement by drill cuttings method, borehole pressure relief in high stress areas of roadway sides, etc. Especially during the borehole pressure relief process of roadway sides, the distribution of high stress areas inside the coal body will cause the amount of coal powder generated during drilling in some areas to increase sharply. The extrusion of the hole wall on the drill pipe generates greater drilling resistance. At the same time, since pneumatic drills are mostly used for underground drilling, the drilling power is low, and the accumulation of coal powder in the hole is likely to cause phenomena such as hole collapse and drill sticking. Therefore, the discharge of coal powder is an important problem to be solved during the drilling process.

[0003] Traditional solutions mostly rely on the threads of the drill itself or the method of water drilling to assist in chip removal. While drilling, water is injected from inside the drill pipe, and the flow of water is used to assist in discharging the coal powder in the borehole. However, water injection may still cause the coal powder to stick and cannot be discharged in time. On the one hand, it causes drill sticking, and on the other hand, it blocks the borehole and reduces the borehole effect.

[0004] Therefore, there is an urgent need to provide a technical solution to address the deficiencies of the above-mentioned existing technologies. Summary of the Invention

[0005] The purpose of this application is to provide a carbon dioxide phase change blasting assisted chip removal device and method to solve or alleviate the problems existing in the above-mentioned existing technologies.

[0006] To achieve the above purpose, this application provides the following technical solutions:

[0007] This application provides a carbon dioxide phase change blasting assisted chip removal device, including: an oscillating jet drill bit, a spiral jet drill pipe, and a carbon dioxide phase change tube; both ends of the spiral jet drill pipe are detachably connected to the oscillating jet drill bit and the carbon dioxide phase change tube respectively; a plurality of oscillating jet holes are provided on the oscillating jet drill bit, spiral exhaust holes are provided on the spiral jet drill pipe, a carbon dioxide activation cavity is provided in the carbon dioxide phase change tube, and a carbon dioxide phase change unit is provided in the carbon dioxide activation cavity. The carbon dioxide phase change unit is used to induce the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity through an activation circuit, and release the carbon dioxide converted into a gaseous state from the spiral exhaust holes and the oscillating jet holes, so as to cause the oscillating jet drill bit and the spiral jet drill pipe to generate rotational vibration.

[0008] Preferably, the oscillating jet drill bit comprises: a drill bit body, a rotating core and a rotating impeller; the rotating core and the rotating impeller are both floatingly installed in the drill bit body, and the rotating impeller is coaxially installed at the end of the rotating core to drive the rotating core to rotate; a plurality of oscillating jet holes are arranged on the drill bit body; a first axial hole and a plurality of flow holes are arranged on the rotating core, the plurality of flow holes are located on the same side of the rotating core, and each flow hole communicates with the first axial hole.

[0009] Preferably, the spiral exhaust holes include clockwise spiral exhaust holes and counterclockwise spiral exhaust holes; the spiral jet drill pipe comprises: a drill pipe body; a second axial hole and an exhaust hole group are arranged on the drill pipe body; the second axial hole is coaxial with the first axial hole; the exhaust hole group includes: a plurality of groups of clockwise exhaust hole groups and a plurality of groups of counterclockwise exhaust hole groups, and the plurality of groups of clockwise exhaust hole groups and the plurality of groups of counterclockwise exhaust hole groups are arranged at intervals and alternately along the axial direction of the second axial hole; wherein, each group of clockwise exhaust hole groups includes a plurality of clockwise spiral exhaust holes arranged circumferentially, and each group of counterclockwise exhaust hole groups includes a plurality of counterclockwise spiral exhaust holes arranged circumferentially; the clockwise spiral exhaust holes and the counterclockwise spiral exhaust holes are both communicated with the second axial hole.

[0010] Preferably, the spiral jet drill pipe further comprises: an axial flow limiting ring, and the axial flow limiting ring is sleeved in the second axial hole; wherein, there are a plurality of axial flow limiting rings, and there is at least one axial flow limiting ring between the clockwise exhaust hole group and the counterclockwise exhaust hole group.

[0011] Preferably, the carbon dioxide phase change unit comprises: an activation tube, the activation tube is located in the carbon dioxide activation cavity, and activation electrodes are respectively arranged at both ends of the activation tube; an activation switch, the activation switch is installed on the inner side wall of the carbon dioxide activation cavity and is used for connecting or disconnecting the activation circuit; a transformer, the transformer is installed on the carbon dioxide phase change tube and is electrically connected to the activation electrodes through the activation circuit.

[0012] Preferably, an injection port and a discharge port are respectively arranged at both ends of the carbon dioxide phase change tube, and the injection port and the discharge port are respectively communicated with both ends of the carbon dioxide activation cavity; a first one-way valve and a second one-way valve are respectively arranged at the injection port and the discharge port.

[0013] Preferably, a magnetic attraction unit controlled by the activation circuit is further arranged between the second one-way valve and the carbon dioxide activation cavity; wherein, the magnetic attraction unit is of a normally closed structure, and the opening and closing of the magnetic attraction unit are synchronized with the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity.

[0014] The embodiment of the present application further provides a method for chip removal assisted by carbon dioxide phase change blasting, including: constructing by using the carbon dioxide phase change blasting assisted chip removal device described in any one of the above. The method includes: Step S101, injecting liquid carbon dioxide into the carbon dioxide phase change pipe; Step S102, in response to the liquid carbon dioxide filling the carbon dioxide activation cavity, the activation circuit is automatically connected, and the carbon dioxide phase change unit is started to induce the phase change of the liquid carbon dioxide, converting it into gaseous carbon dioxide and releasing it to the spiral air jet drill pipe; Step S103, the gaseous carbon dioxide enters the air jet spiral drill pipe and is discharged through the spiral exhaust holes on the air jet spiral drill pipe to generate a jet airflow, while jetting chips and rotating and vibrating the spiral air jet drill pipe; Step S104, the gaseous carbon dioxide enters the oscillating air jet drill bit through the air jet spiral drill pipe and jets in different directions into the drill hole through the oscillating air jet holes on the oscillating air jet drill bit, while discharging chips and oscillating and loosening the drill pipe of the spiral air jet drill pipe. Beneficial effects

[0015] In the carbon dioxide phase change blasting assisted chip removal device provided by the embodiment of the present application, both ends of the spiral air jet drill pipe are detachably connected to the oscillating air jet drill bit and the carbon dioxide phase change pipe respectively. A plurality of oscillating air jet holes are provided on the oscillating air jet drill bit, spiral exhaust holes are provided on the spiral air jet drill pipe, and a carbon dioxide phase change unit is provided in the carbon dioxide activation cavity of the carbon dioxide phase change pipe. The carbon dioxide phase change unit induces the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity through the activation circuit, converting it into a gas state, and the converted gaseous carbon dioxide is released through the spiral exhaust holes and the oscillating air jet holes, so that the oscillating air jet drill bit and the spiral air jet drill pipe generate vibrations respectively, and while dredging the drill hole, the drill pipe itself can be vibrated to move the drill pipe, solving the problem of drill pipe jamming caused by hole collapse and coal powder blockage.

[0016] Therefore, on the one hand, chip removal in the drill hole is carried out through the high pressure generated instantaneously by the carbon dioxide phase change, solving the blockage problem caused by too much coal powder. Moreover, the carbon dioxide gas generated by the carbon dioxide phase change has a large expansion coefficient and good fluidity, and will not cause the coal powder to adhere during the chip removal process, and the chip removal efficiency is high; on the other hand, the phase change blasting of liquid carbon dioxide is a cold blasting, and no harmful gases and open flames will be generated during the whole process, which can ensure the safety of the blasting process; at the same time, liquid carbon dioxide is convenient for storage and transportation and is more suitable for the underground coal mine environment. Description of the drawings

[0017] The specification drawings constituting a part of the present application are used to provide a further understanding of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. Among them:

[0018] Figure 1Schematic structural diagram of a carbon dioxide phase change blasting assisted chip removal device provided according to some embodiments of the present application;

[0019] Figure 2 Schematic cross-sectional structural diagram of an oscillating jet drill bit provided according to some embodiments of the present application;

[0020] Figure 3 For Figure 2 Side view of the shown oscillating jet drill bit;

[0021] Figure 4 Schematic structural diagram of a rotating impeller provided according to some embodiments of the present application;

[0022] Figure 5 Schematic cross-sectional structural diagram of a spiral jet drill pipe provided according to some embodiments of the present application;

[0023] Figure 6 For Figure 5 Schematic structural diagram of the clockwise spiral exhaust holes in the shown spiral jet drill pipe;

[0024] Figure 7 For Figure 5 Schematic structural diagram of the counterclockwise spiral exhaust holes in the shown spiral jet drill pipe;

[0025] Figure 8 Schematic installation diagram of a second one-way valve in a phase change outer pipe provided according to some embodiments of the present application;

[0026] Figure 9 Schematic assembly diagram of a phase change inner pipe provided according to some embodiments of the present application;

[0027] Figure 10 For Figure 9 Cross-sectional view of the shown phase change inner pipe;

[0028] Figure 11 Schematic structural diagram of a phase change inner pipe provided according to some embodiments of the present application;

[0029] Figure 12 Schematic structural diagram of a constant pressure valve provided according to some embodiments of the present application;

[0030] Figure 13 Flowchart of a carbon dioxide phase change blasting assisted chip removal method provided according to some embodiments of the present application.

[0031] Explanation of reference numerals:

[0032] 100, oscillating jet drill bit; 200, spiral jet drill pipe; 300, carbon dioxide phase change pipe; 400, first one-way valve; 500, second one-way valve;

[0033] 101, drill bit body; 102, rotating core; 103, rotating impeller; 201, drill pipe body; 202, axial flow limiting ring; 203, clockwise spiral exhaust hole; 204, counterclockwise spiral exhaust hole; 301, phase change outer tube; 302, phase change inner tube; 303, activation tube; 304, activation switch; 305, constant pressure valve; 306, threaded connecting rod; 307, transformer; 308, phase change tube power supply; 309, magnetic attraction unit; 312, switch through hole; 322, threaded mounting hole; 332, mounting groove; 342, circumferential wire groove; 352, axial wire groove; 314, power-off spring; 324, energized conductor; 315, square slot hole. Detailed implementation manners

[0034] The present application will be described in detail below with reference to the drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present application rather than a limitation of the present application. In fact, those skilled in the art will clearly understand that modifications and variations can be made to the present application without departing from the scope or spirit of the present application. For example, features shown or described as part of one embodiment can be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the present application includes such modifications and variations within the scope of the appended claims and their equivalents.

[0035] In solving the problem of discharging pulverized coal during drilling, the traditional method of relying on the threads of the drill itself or the auxiliary chip removal method of a water drill is inefficient in solving the chip removal problem during drilling. The pulverized coal chip removal is not timely, which is extremely likely to cause problems such as hole collapse, hole blockage, and drill sticking. Based on this, the applicant proposes a carbon dioxide phase change blasting-assisted chip removal device, which uses the high pressure generated instantaneously by the carbon dioxide phase change to remove chips during drilling. While dredging the drill hole, it can make the drill pipe vibrate itself and move the drill pipe to solve the problems of hole collapse, blockage caused by pulverized coal blockage, and drill sticking. As Figures 1 to 12 shown, the carbon dioxide phase change blasting-assisted chip removal device includes: an oscillating jet drill bit 100, a spiral jet drill pipe 200, and a carbon dioxide phase change tube 300. Among them, the two ends of the spiral jet drill pipe 200 are respectively detachably connected to the oscillating jet drill bit 100 and the carbon dioxide phase change tube 300. For the convenience of description, in the present application, along the axial direction of the chip removal device, the direction of the oscillating jet drill bit 100 is the front end, and the direction of the carbon dioxide phase change tube 300 is the rear end; that is to say, the direction from the carbon dioxide phase change tube 300 to the oscillating jet drill bit 100 is from the rear to the front.

[0036] The oscillating jet bit 100 includes a bit body 101, a rotating core 102, and a rotating impeller 103. The rotating core 102 and the rotating impeller 103 are both installed inside the bit body 101, and the rotating impeller 103 is coaxially installed at the end of the rotating core 102. The rock formation drives the rotating core 102 to rotate. Specifically, a bullet-shaped mounting hole with a conical head and a cylindrical tail is axially provided on the bit body 101. The rotating core 102 is floatingly installed in the bullet-shaped mounting hole, and its outer shape is the same as that of the bullet-shaped mounting hole. The rotating impeller 103 is fixedly connected to the tail of the rotating core 102 and is located inside the bullet-shaped mounting hole at the same time. In a specific example, the rotating core 102 is a thin-walled structure, with a conical front end and a cylindrical rear end, and the rotating impeller 103 is arranged at the open end of the cylindrical tail so that the airflow is ejected from the inside to the outside in the thin-walled structure of the rotating core 102 after passing through the rotating impeller 103.

[0037] A plurality of oscillating jet holes are provided on the oscillating jet bit 100. Specifically, a plurality of oscillating jet holes are provided on the bit body 101. The plurality of oscillating jet holes extend radially along the bullet-shaped mounting hole and penetrate through the outer wall of the bit body 101. A first axial hole and a plurality of flow holes are provided on the rotating core 102. Among them, the plurality of flow holes are located on the same side of the rotating core 102, and each flow hole communicates with the first axial hole.

[0038] That is to say, the flow holes are arranged on the same side of the axis of the rotating core 102. Since a plurality of blades are circumferentially arranged on the rotating impeller 103, the airflow entering from the tail of the rotating impeller 103 will push the rotating impeller 103 to rotate, and at the same time drive the rotating core 102 to rotate in the bullet-shaped mounting hole. The airflow also enters the bullet-shaped mounting hole from the flow holes along the first axial hole, and then a rotating airflow is formed in the bullet-shaped mounting hole, further pushing the rotating core 102 to rotate, and is ejected from the oscillating jet holes and released to the surroundings of the bit body 101, driving the bit body 101 to oscillate.

[0039] At the tail of the oscillating jet bit 100, a first internal thread hole is provided. At the front end of the spiral jet drill pipe 200, a first external thread boss is provided. Through the cooperation of the first internal thread hole and the first external thread boss, the oscillating jet bit is threadedly connected to the spiral jet drill pipe 200. Thereby, the front end of the spiral jet drill pipe 200 is threadedly connected to the tail of the oscillating jet bit 100, and the rotating core 102 and the rotating impeller 103 are axially limited by the spiral jet drill pipe 200 to prevent the axial movement of the rotating core 102 and the rotating impeller 103.

[0040] Meanwhile, spiral exhaust holes are also provided on the spiral jet drill pipe 200. Through the spiral exhaust holes, the air flow passing through the spiral jet drill pipe 200 is released from the inside of the spiral jet drill pipe 200 to the outside, pushing the spiral jet drill pipe 200 to rotate and oscillate. Further, a clockwise spiral exhaust hole 203 and a counterclockwise spiral exhaust hole 204 are provided on the spiral jet drill pipe 200.

[0041] Specifically, the spiral jet drill pipe 200 includes: a drill pipe body 201 and an axial flow limiting ring 202. A second axial hole and an exhaust hole group are provided on the drill pipe body 201; wherein, the second axial hole is coaxial with the first axial hole and penetrates the drill pipe body 201 along the axial direction; the exhaust hole group includes multiple clockwise exhaust hole groups and multiple counterclockwise exhaust hole groups. The multiple clockwise exhaust hole groups and the multiple counterclockwise exhaust hole groups are arranged at intervals and alternately along the axial direction of the second axial hole. Each clockwise exhaust hole group includes multiple clockwise spiral exhaust holes 203 arranged circumferentially, and each counterclockwise exhaust hole group includes multiple counterclockwise spiral exhaust holes 204 arranged circumferentially. Each clockwise spiral exhaust hole 203 and each counterclockwise spiral exhaust hole 204 communicate with the second axial hole. Thereby, the air flow released from the tail end to the front end of the spiral jet drill pipe 200 will flow in the second axial hole towards the second axial hole, and during the flowing process, it will be ejected and released outward by the exhaust hole group, pushing the spiral jet drill pipe 200 to oscillate.

[0042] With the help of the alternately arranged clockwise spiral exhaust hole groups 203 and counterclockwise spiral exhaust hole groups 204, a part of the air flow passing through the second axial hole is discharged from the clockwise spiral exhaust holes 203 and the counterclockwise spiral exhaust holes 204 in sequence. Under the pushing action of the air flow, the oscillation effect of the spiral jet drill pipe 200 is effectively improved.

[0043] An axial flow limiting ring 202 is also installed in the second axial hole. Specifically, the axial flow limiting ring 202 is sleeved in the second axial hole. Among them, there are multiple axial flow limiting rings 202, and at least one axial flow limiting ring 202 is provided between adjacent clockwise exhaust hole groups and counterclockwise exhaust hole groups. Thereby, through the axial flow limiting ring 202, the air flow flowing forward in the second axial hole is blocked to a certain extent, so that the air flow preferentially passes through the spiral exhaust holes and is discharged, causing the spiral jet drill pipe 200 to generate rotational oscillation.

[0044] In a specific example, the axial flow limiting ring 202 is in an annular structure, and the inner diameter of the ring is slightly smaller than the diameter of the spiral exhaust hole, so as to reduce the effective flow area of the air flow passing through the second axial hole, increase the air flow resistance, and ensure that the air flow is preferentially discharged from the spiral exhaust hole. In addition, the flow limiting ring is arranged in the second axial hole and fixed to the drill pipe body 201 by means of threaded connection or the like. That is to say, when the second axial hole is an internal threaded hole, an external thread is arranged on the outer side wall of the axial flow limiting ring 202. During the installation of the axial flow limiting ring 202, the axial flow limiting ring 202 can be screwed into the second axial hole by means of a tool.

[0045] At the tail of the drill pipe body 201, a second external thread boss is arranged. At the front end of the carbon dioxide phase change pipe 300, a second internal threaded hole is arranged. Through the cooperation of the second external thread boss and the second internal threaded hole, the drill pipe body 201 is threadedly connected to the carbon dioxide phase change pipe 300.

[0046] And a carbon dioxide activation cavity is arranged in the carbon dioxide phase change pipe 300. A carbon dioxide phase change unit is arranged in the carbon dioxide activation cavity. The carbon dioxide phase change unit is used to induce the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity through an activation circuit, changing from a liquid state to a gaseous state. The carbon dioxide transformed into a gaseous state flows through the second axial hole and the first axial hole and is discharged through the spiral exhaust hole and the oscillating jet hole, so that the spiral jet drill rod 200 and the oscillating jet drill bit 100 perform oscillating rotation.

[0047] Among them, the carbon dioxide phase change unit includes: an activation tube 303, an activation switch 304 and a transformer 307. The activation tube 303 is located in the carbon dioxide activation cavity. Activation electrodes are respectively arranged at both ends of the activation tube 303. After being powered on, an electric arc can be generated between the activation electrodes at both ends, causing the activation tube 303 to instantly heat up, inducing the phase change of the liquid carbon dioxide, changing from a liquid state to a gaseous state, and at the same time, the volume expands highly.

[0048] The activation switch 304 is installed on the inner side wall of the carbon dioxide activation cavity and is used to connect or disconnect the activation circuit. Specifically, the activation switch 304 includes a current-carrying conductor 324 and a power-off spring 314. One end of the power-off spring 314 is fixed to the outer side wall of the activation tube 303, and the other end is connected to the current-carrying conductor 324. Specifically, two switch partitions parallel to each other are arranged along the radial direction on the outer side wall of the activation tube 303. The activation switch 304 is installed between the two switch partitions; the switch partitions extend along the radial direction of the activation tube 303, and the upper ends are abutted against the inner side wall of the carbon dioxide activation cavity; the width of the current-carrying conductor 324 is adapted to the distance between the outer side walls of the two switch partitions.

[0049] When there is no liquid carbon dioxide filled in the carbon dioxide activation cavity, under the action of the power-off spring 314, the energized conductor 324 is pulled and pressed against the top surface of the switch partition. The energized conductor 324 is not connected to the activation circuit, and the activation circuit is in an open state; when the carbon dioxide activation cavity is filled with liquid carbon dioxide, under the action of pressure, the energized conductor 324 disengages from the top surface of the switch partition and floats upward to connect the activation circuit.

[0050] After the activation circuit is connected, an arc is generated between the activation electrodes at both ends to heat the activation tube 303. Here, an arc is generated between the activation electrodes at both ends through the voltage difference between the activation electrodes at both ends to heat the activation tube 303. Specifically, the voltage difference between the activation electrodes at both ends is generated by the transformer 307 installed on the carbon dioxide phase change tube 300, where the transformer 307 is electrically connected to the activation electrodes through the activation circuit.

[0051] Furthermore, the transformer 307 is bolted or embedded in the tail of the carbon dioxide phase change tube 300. At the same time, a rechargeable phase change tube power supply 308 is installed at the tail of the carbon dioxide phase change tube 300, and the phase change tube power supply 308 is connected to the transformer 307 to achieve power supply. Specifically, the carbon dioxide phase change tube 300 includes: a phase change inner tube 302 and a phase change outer tube 301. After the phase change inner tube 302 is sleeved on the phase change outer tube 301 from the tail end of the phase change outer tube 301, the tail ends of the phase change inner tube 302 and the phase change outer tube 301 are fixedly connected (such as welded). On the outer side wall of the phase change inner tube 302, a switch through hole 312 adapted to the energized conductor 324 is provided, and at the same time, a threaded mounting hole 322 is provided. The activation tube 303 is fixedly installed in the phase change inner tube 302 through a threaded connecting rod 306. Specifically, after the activation tube 303 is inserted into the activation tube 303 from the front end of the phase change inner tube 302, both ends of the threaded connecting rod 306 are respectively connected to the threaded mounting hole 322 and the outer side wall of the activation tube 303 to fix the activation tube 303 in the phase change inner tube 302.

[0052] On the outer side wall at the tail end of the phase change inner tube 302, two mounting grooves 332 are symmetrically provided. The two mounting grooves 332 are respectively used to install the phase change tube power supply 308 and the transformer 307. At the same time, the two mounting grooves 332 are connected through a circumferential wire groove 342 provided therebetween; on the outer side wall of the phase change tube, an axial wire groove 352 is provided along the axial direction. The axial wire groove 352 is used to install the activation circuit, and the axial wire groove 352 communicates with the switch through hole 312.

[0053] In addition, an injection port and a discharge port are respectively arranged at both ends of the carbon dioxide phase change tube 300. The injection port and the discharge port are respectively communicated with both ends of the carbon dioxide activation cavity. A first one-way valve 400 and a second one-way valve 500 are respectively arranged at the injection port and the discharge port. Through the first one-way valve 400 and the second one-way valve 500, it is further ensured that after the liquid carbon dioxide is transformed into gas in the carbon dioxide activation cavity, it flows unidirectionally from the tail of the carbon dioxide phase change tube 300 towards the oscillating jet bit 100. Specifically, the injection port is located at the tail end of the phase change inner tube 302, the discharge port is located at the front end of the phase change outer tube 301, the first one-way valve 400 is installed at the tail end of the phase change inner tube 302, and the second one-way valve 500 is installed at the front end of the phase change outer tube 301.

[0054] Furthermore, a magnetic attraction unit 309 controlled by an activation circuit is also arranged between the second one-way valve 500 and the carbon dioxide activation cavity. Specifically, a square slot 315 is arranged on the carbon dioxide phase change tube 300. The magnetic attraction unit 309 is installed in the square slot 315 and includes a magnetic attraction ring and a normally closed valve. The magnetic attraction ring is closely attached (such as pasted) to the inner side wall of the square slot 315, and along the radial direction of the carbon dioxide phase change tube 300, two mutually cooperating normally closed valves are pressed tightly by a compression spring to seal the front end of the carbon dioxide activation cavity.

[0055] In a specific example, a constant pressure valve 305 is installed (threadedly connected) at the front end of the phase change inner tube 302. A square slot 315 is arranged axially on the constant pressure valve 305. The magnetic attraction unit 309 is installed in the square slot 315, and the magnetic attraction unit 309 is electrically connected to the activation circuit. That is to say, the opening and closing of the magnetic attraction unit 309 are synchronized with the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity. The two normally closed valves of the magnetic attraction unit 309 are abutted and normally closed under the action of the compression spring pressure to seal the front end of the phase change inner tube 302. When the activation circuit is turned on, the magnetic attraction ring generates an electromagnetic force to attract the normally closed valve, compresses the compression spring, and the two normally closed valves move radially in the square slot 315 and separate from each other, so that the carbon dioxide transformed into gas is released from the carbon dioxide activation cavity towards the second one-way valve 500.

[0056] Thereby, through the activation circuit, the liquid carbon dioxide filled in the carbon dioxide activation cavity is induced to undergo a phase change, transformed into gas, flows towards the spiral jet drill pipe 200 and the oscillating jet bit 100, and is respectively released through the spiral exhaust holes and the oscillating jet holes, so that the oscillating jet bit 100 and the spiral jet drill pipe 200 respectively generate rotational vibrations, and while dredging the drill hole, the drill pipe itself can vibrate and move the drill pipe, solving the problem of drill pipe jamming caused by hole collapse and coal powder blockage.

[0057] The embodiment of the present application also provides a method for chip removal assisted by carbon dioxide phase change blasting. This method uses the carbon dioxide phase change blasting assisted chip removal device described in any of the above embodiments for construction. As Figure 13 shown, the method for chip removal assisted by carbon dioxide phase change blasting includes:

[0058] Step S1301: Inject liquid carbon dioxide into the carbon dioxide phase change tube 300;

[0059] Step S1302: In response to the liquid carbon dioxide filling the carbon dioxide activation cavity, the activation circuit is automatically connected, and the carbon dioxide phase change unit is started, inducing the liquid carbon dioxide to undergo a phase change, converting into gaseous carbon dioxide, and releasing it to the spiral jet drill pipe 200;

[0060] Step S1303: The gaseous carbon dioxide enters the jet spiral drill pipe and is discharged through the spiral exhaust holes on the jet spiral drill pipe, generating a jet airflow, which oscillates the spiral jet drill pipe 200 while removing chips;

[0061] Step S1304: The gaseous carbon dioxide enters the oscillating jet bit 100 through the jet spiral drill pipe and jets in different directions into the borehole through the oscillating jet holes on the oscillating jet bit 100, removing chips while oscillating the spiral jet drill pipe 200 and loosening the drill pipe.

[0062] Thereby, on the one hand, high-pressure is generated instantaneously by the carbon dioxide phase change for borehole chip removal, solving the blockage problem caused by excessive pulverized coal. Moreover, the carbon dioxide gas generated by the carbon dioxide phase change has a large expansion coefficient and good fluidity, and will not cause the pulverized coal to adhere during the chip removal process, with high chip removal efficiency; on the other hand, the phase change blasting of liquid carbon dioxide is a cold blasting, and no harmful gases and open flames will be generated during the whole process, ensuring the safety of the blasting process; at the same time, liquid carbon dioxide is convenient for storage and transportation and is more suitable for the underground coal mine environment.

[0063] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A carbon dioxide phase change blasting assisted chip removal device, characterized in that, Comprising: An oscillating jet bit, a spiral jet drill pipe, and a carbon dioxide phase change tube; both ends of the spiral jet drill pipe are detachably connected to the oscillating jet bit and the carbon dioxide phase change tube respectively; A plurality of oscillating jet holes are provided on the oscillating jet bit, spiral exhaust holes are provided on the spiral jet drill pipe, a carbon dioxide activation cavity is provided in the carbon dioxide phase change tube, and a carbon dioxide phase change unit is provided in the carbon dioxide activation cavity. The carbon dioxide phase change unit is used to induce the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity through an activation circuit, and release the carbon dioxide converted into a gaseous state through the spiral exhaust holes and the oscillating jet holes, so as to cause the oscillating jet bit and the spiral jet drill pipe to generate rotational vibration; The oscillating jet bit includes: a bit body, a rotating core, and a rotating impeller; the rotating core and the rotating impeller are both floatingly installed in the bit body, and the rotating impeller is coaxially installed at the end of the rotating core to drive the rotating core to rotate; a plurality of the oscillating jet holes are provided on the bit body; a first axial hole and a plurality of flow holes are provided on the rotating core, the plurality of flow holes are located on the same side of the rotating core, and each flow hole communicates with the first axial hole.

2. The carbon dioxide phase change blasting-assisted chip removal device according to claim 1, wherein, The spiral exhaust holes include clockwise spiral exhaust holes and counterclockwise spiral exhaust holes; The spiral jet drill pipe includes: a drill pipe body; a second axial hole and an exhaust hole group are provided on the drill pipe body; the second axial hole is coaxial with the first axial hole; The exhaust hole group includes: a plurality of groups of clockwise exhaust hole groups and a plurality of groups of counterclockwise exhaust hole groups, and the plurality of groups of clockwise exhaust hole groups and the plurality of groups of counterclockwise exhaust hole groups are arranged at intervals and alternately along the axial direction of the second axial hole; Wherein, each group of the clockwise exhaust hole groups includes a plurality of the clockwise spiral exhaust holes arranged circumferentially, and each group of the counterclockwise exhaust hole groups includes a plurality of the counterclockwise spiral exhaust holes arranged circumferentially; the clockwise spiral exhaust holes and the counterclockwise spiral exhaust holes are both communicated with the second axial hole.

3. The carbon dioxide phase change blasting assisted chip removal device according to claim 2, wherein The spiral jet drill pipe further includes: an axial flow limiting ring, and the axial flow limiting ring is sleeved in the second axial hole; Wherein, there are a plurality of the axial flow limiting rings, and there is at least one axial flow limiting ring between the clockwise exhaust hole group and the counterclockwise exhaust hole group.

4. The carbon dioxide phase change blasting-assisted chip removal device according to claim 1, wherein The carbon dioxide phase change unit includes: An activation tube, the activation tube is located in the carbon dioxide activation cavity, and activation electrodes are respectively arranged at both ends of the activation tube; An activation switch, the activation switch is installed on the inner side wall of the carbon dioxide activation cavity and is used to connect or disconnect the activation circuit; A transformer, the transformer is installed on the carbon dioxide phase change tube and is electrically connected to the activation electrode through the activation circuit.

5. The carbon dioxide phase change blasting assisted chip removal device according to claim 1, characterized in that, Both ends of the carbon dioxide phase change tube are respectively provided with an injection port and a discharge port, and the injection port and the discharge port are respectively communicated with both ends of the carbon dioxide activation cavity; A first one-way valve and a second one-way valve are respectively arranged at the injection port and the discharge port.

6. The carbon dioxide phase change blasting assisted chip removal device according to claim 5, wherein, A magnetic attraction unit controlled by the activation circuit is further arranged between the second one-way valve and the carbon dioxide activation cavity; wherein, the magnetic attraction unit is of a normally closed structure, and the opening and closing of the magnetic attraction unit are synchronized with the phase change of the liquid carbon dioxide filled in the carbon dioxide activation cavity.

7. A method for chip removal assisted by carbon dioxide phase change blasting, characterized in that, including: When constructing by using the carbon dioxide phase change blasting assisted chip removal device according to any one of claims 1-6, the method includes: Step S101, injecting liquid carbon dioxide into the carbon dioxide phase change pipe; Step S102, in response to the liquid carbon dioxide filling the carbon dioxide activation cavity, the activation circuit is automatically connected, the carbon dioxide phase change unit is started, inducing the liquid carbon dioxide to undergo a phase change, converting into gaseous carbon dioxide, and releasing it to the spiral jet drill pipe; Step S103, the gaseous carbon dioxide enters the spiral jet drill pipe and is discharged through the spiral exhaust holes on the spiral jet drill pipe, generating a jet airflow, while jetting chips and causing the spiral jet drill pipe to oscillate; Step S104, the gaseous carbon dioxide enters the oscillating jet bit through the spiral jet drill pipe, and jets in different directions into the drill hole through the oscillating jet holes on the oscillating jet bit, while jetting chips and causing the spiral jet drill pipe to oscillate and loosen.

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