A composite impact drilling tool

Abstract

The present invention discloses a composite impact drilling tool, which includes a sleeve. Inside the sleeve, a self-excited oscillation cavity, an end cap and a hammer base are sequentially arranged from top to bottom along the length direction. Inside the hammer base, an impact hammer and a commutation seat are sequentially arranged. Inside the impact hammer, a commutation sleeve is arranged. Inside the commutation seat, a main nozzle is arranged. The lower end of the hammer base is connected to a drill bit. Both the end cap and the commutation sleeve are provided with central holes along the axial direction, and high-pressure drilling fluid passes through the central flow path composed of the central holes of the end cap, the commutation sleeve and the main nozzle. The present invention can generate axial and torsional impacts simultaneously, effectively increase the drilling pressure, reduce the stick-slip phenomenon, and is a composite impactor with a simple structure and reliable operation.

Description

Technical Field

[0001] The present invention relates to the technical field of drilling tools, and particularly to a compound impact drilling tool. Background Art

[0002] Improving the mechanical drilling rate of deep hard formations is an eternal goal in the drilling industry. The impact rock-breaking drilling technology is an efficient rock-breaking technology with good application effects in current deep well and ultra-deep well drilling in hard formations. Among the current drilling speed-up tools, the impactor with a single axial impact function is suitable for hard and brittle and hard plastic formations, which can improve the rock-breaking efficiency of the drill bit, but is prone to instantaneous "stick-slip" phenomenon. Due to excessive axial impact, the drill bit may penetrate too deep into the formation, increasing the rock-breaking torque while increasing the mechanical drilling rate, and further exacerbating the stick-slip vibration of the drill bit. The impactor with a single circumferential impact function is suitable for hard interbedded formations, which can apply circumferential impact torque to eliminate the "stick-slip" phenomenon of the drill bit, but cannot apply axial impact load to increase the penetration depth of the drill bit teeth. That is, the two types of tools have their own advantages and disadvantages. Therefore, under the urgent demand for oil resource exploration and development in China and the general situation of drilling marketization, it is very necessary to propose a practical drilling technology and its supporting tools that can further improve the mechanical drilling rate and drilling efficiency of deep hard formations and complex formations. Proposing new rock-breaking drill tools is of great significance in drilling speed-up.

[0003] The traditional rotary impact drilling and torsional impact drilling have a single impact mode dimension. In order to reduce or eliminate the "stick-slip" phenomenon of the drill bit in hard formations and improve the penetration depth of the drill bit teeth by applying axial impact load to further improve the rock-breaking efficiency of the drill bit, a new type of compound impact drilling tool is proposed, which combines the advantages of axial impact and torsional impact drilling and rock-breaking. The basic idea is to combine the axial pulsating impact and torsional impact rock-breaking methods and convert the energy of drilling fluid into high-frequency impact mechanical energy of axial and torsional alternation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a compound impact drilling tool that can generate axial and torsional impacts simultaneously, effectively increase the drilling pressure, reduce the stick-slip phenomenon, and has a simple structure and reliable operation, aiming at the above-mentioned defects existing in the prior art.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0006] A compound impact drilling tool includes a sleeve. An auto-oscillation cavity, an end cover, and a hammer base are sequentially arranged in the sleeve from top to bottom along the length direction. An impact hammer and a commutation seat are sequentially arranged in the hammer base. A commutation sleeve is arranged in the impact hammer, and a main nozzle is arranged in the commutation seat. The lower end of the hammer base is connected to a drill bit. The end cover and the commutation sleeve are both provided with central holes along the axial direction. High-pressure drilling fluid passes through the central flow path composed of the central holes of the end cover, the commutation sleeve, and the main nozzle.

[0007] According to the above technical solution, the central hole of the reversing sleeve penetrates the reversing sleeve vertically. The drilling fluid enters the central hole of the reversing sleeve and then flows downward. Part of the drilling fluid enters the central hole of the reversing sleeve, and part enters between the impact hammer and the hammer base. The drilling fluid entering between the impact hammer and the hammer base can drive the impact hammer to rotate, and then reciprocally impact the hammer base, and transmit the impact torque to the hammer base, and then transmit it to the drill bit through the hammer base.

[0008] According to the above technical solution, a locking ring is provided between the hammer base and the sleeve for axial positioning and installation. The locking ring includes a plurality of sector-shaped locking blocks distributed circumferentially. The lower part of the sleeve is connected to the hammer base through splines, and the rock-breaking torque of the drill bit is transmitted through spline fitting.

[0009] According to the above technical solution, the bottom of the reversing sleeve has a guiding surface in contact with the guiding surface of the reversing seat. A guiding surface is provided at the top of the reversing sleeve in contact with the lower guiding surface of the end cover, so that both the upper and lower ends of the reversing sleeve are restricted radially, and the reversing sleeve has the support of the guiding surface during rotation. There are two stepped holes of different sizes under the end cover, a set of large holes and a set of small holes up and down, which are respectively used for guiding and installing the impact hammer and the reversing sleeve.

[0010] According to the above technical solution, an upper nozzle, a resonant cavity chamber and a lower nozzle are successively arranged axially from top to bottom on the self-excited oscillation cavity, and a collision wall is provided at the outlet end of the resonant cavity chamber.

[0011] According to the above technical solution, a plurality of connection holes are arranged circumferentially at the bottom of the end cover. The end cover is connected and fixed to the hammer base through bolts or screws, and the bolts or screws pass through the connection holes and are connected to the hammer base.

[0012] According to the above technical solution, the nozzle diameter of the main nozzle is smaller than the diameter of the central hole of the reversing sleeve.

[0013] According to the above technical solution, a plurality of drainage grooves are distributed circumferentially on the inner circle of the hammer base, and the reversing seat has convex edges clamped in the drainage grooves;

[0014] The opposite sides of the convex edges are in contact with the plane of the drainage groove, so that the reversing seat can remain relatively stationary with the hammer base. When the hammer base rotates, the reversing seat rotates together with the hammer base. The reversing sleeve installed in the hammer base is located above the reversing seat, and the reversing sleeve has a central hole for the drilling fluid to flow through.

[0015] According to the above technical solution, a plurality of side flow channels are distributed circumferentially on the side wall of the end cover. The side flow channels are communicated with the central hole of the end cover. A plurality of second diversion grooves are distributed circumferentially on the outer circle of the hammer base. The second diversion grooves are communicated with the side flow channels. A sub-nozzle is provided at the bottom of the second diversion groove, and the sub-nozzle is communicated with the bottom of the central hole of the hammer base;

[0016] The inner ring of the hammer base is provided with an impact chamber. A hammer head is arranged outside the impact hammer, and the hammer head is arranged in the impact chamber. Third diversion holes are arranged on both sides of the hammer head along the length direction of the impact hammer, and the third diversion holes are communicated with the impact chamber; a plurality of first diversion holes are circumferentially distributed on the commutator sleeve along the central hole of the commutator sleeve, and the central hole of the commutator sleeve is communicated with the third diversion holes through the first diversion holes;

[0017] A starting chamber is arranged on the outer wall of the commutator sleeve. An inner key is arranged in the starting chamber. A third diversion groove is arranged on one side of the starting chamber. When the commutator sleeve rotates forward or backward relative to the impact hammer, the third diversion holes are aligned and communicated or misaligned and separated from the third diversion groove;

[0018] The commutator base is provided with a through groove along the axial direction;

[0019] Fourth diversion holes are circumferentially distributed on the inner ring of the hammer base, and the fourth diversion holes are communicated with the second diversion groove. When the commutator sleeve rotates forward or backward relative to the hammer base, the fourth diversion holes are aligned and communicated or misaligned and separated from the starting chamber.

[0020] According to the above technical solution, when the drilling fluid flows into the end cover, part of the drilling fluid flows downward through the central hole of the end cover, the central hole of the reversing sleeve, the reversing seat and the main nozzle. Since the outlet diameter of the main nozzle is small, a high pressure is formed in the channel above the outlet of the main nozzle. The high-pressure drilling fluid sequentially passes through the side flow channel of the end cover, the second diversion groove of the hammer seat, and the fourth diversion hole to enter the starting chamber, pushing the reversing sleeve to rotate counterclockwise around the axis of the tool, and the impact hammer rotates clockwise around the axis of the tool. At this time, it is in the unstarted state; when the left side of the inner key contacts the side of the starting chamber, both stop rotating, and at this time it is in the started state; then the high-pressure drilling fluid enters the gap between the right side of the hammer head and the side of the impact chamber through the first diversion hole and the third diversion hole on the right side of the hammer head. The right side of the hammer head bears high pressure, while the drilling fluid on the left side of the hammer head flows downward through the third diversion hole on the left side of the hammer head, the third diversion groove, and the through groove of the reversing seat. The drilling fluid on the left side of the hammer head is at low pressure. Under the action of the high and low pressure difference on both sides of the hammer head, the impact hammer rotates clockwise around the axis of the hammer seat. At the same time, the impact hammer drives the reversing sleeve to rotate synchronously clockwise through the inner key until the left side of the hammer head hits the inner wall surface of the impact chamber. The impact hammer stops rotating and transmits the impact torque to the hammer seat. At this time, it is the instant of impact. Due to the action of inertia, the reversing sleeve continues to rotate clockwise, and the left side of the inner key disengages from the side of the starting chamber. The high-pressure drilling fluid sequentially passes through the side flow channel of the end cover, the second diversion groove, and the fourth diversion hole to enter the cavity formed by the disengagement of the inner key and the starting chamber. At the same time, the drilling fluid on the other side of the inner key flows downward through the second diversion hole, the drainage groove, and the through groove, making the other side of the inner key at low pressure. The reversing sleeve continues to rotate clockwise under the combined action of inertia and the high and low pressure difference on both sides of the inner key until the right side of the inner key contacts the side of the starting chamber. At this time, it is in the reversing reset state. The reversing sleeve completes the reversing function, and the high and low pressures of the drilling fluid are respectively connected to both sides of the hammer head again. The impact hammer and the reversing sleeve rotate counterclockwise synchronously and impact the hammer seat. This cycle repeats, and the impact hammer continuously impacts the hammer seat reciprocally.

[0021] The present invention has the following beneficial effects:

[0022] The present invention can generate both axial and torsional impacts, effectively improve the drilling pressure, reduce the stick-slip phenomenon, and is a composite impactor with a simple structure and reliable operation; the embodiment of the present invention provides a composite impact drilling tool. Since axial impact and circumferential impact are provided to the drill bit simultaneously, the rock-breaking efficiency of the drill bit is further improved; the axial impact device of this composite impact drilling tool adopts the scheme of generating hydraulic pulses in the self-excited oscillation chamber, canceling the design of the axial impact hammer, and improving the safety and working reliability of the tool; this composite impact drilling tool has a simple structure, is convenient to disassemble, and works reliably. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of the composite impact drilling tool in the embodiment of the present invention;

[0024] Figure 2It is a cross-sectional view of the self-excited oscillation cavity in the embodiment of the present invention;

[0025] Figure 3 It is a perspective view of the end cap in the embodiment of the present invention;

[0026] Figure 4 It is Figure 1 the B-B cross-sectional view of;

[0027] Figure 5 It is Figure 1 the C-C cross-sectional view of;

[0028] Figure 6 It is the A-A cross-sectional view of Figure 1 in the unstarted state in the embodiment of the present invention;

[0029] Figure 7 It is the A-A cross-sectional view of Figure 1 in the starting state in the embodiment of the present invention;

[0030] Figure 8 It is the A-A cross-sectional view of Figure 1 in the impact instant state in the embodiment of the present invention;

[0031] Figure 9 It is the A-A cross-sectional view of Figure 1 in the commutation reset state in the embodiment of the present invention;

[0032] In the figure, 1 - hammer seat; 11 - drain groove; 12 - second diversion groove; 13 - sub-nozzle; 14 - impact chamber; 15 - fourth diversion hole; 16 - second locking groove; 17 - sealing groove; 18 - spline;

[0033] 2 - commutation seat; 21 - convex rib; 22 - through groove;

[0034] 3 - commutation sleeve; 31 - commutation sleeve center hole; 32 - first diversion hole; 33 - starting chamber; 34 - third diversion groove;

[0035] 4 - end cap; 41 - side flow channel; 42 - connection hole; 43 - end cap center hole;

[0036] 5 - impact hammer; 51 - inner key; 52 - second diversion hole; 53 - hammer head; 54 - third diversion hole;

[0037] 6 - sleeve; 61 - sleeve center hole; 62 - first locking groove;

[0038] 7 - locking block; 8 - sealing ring; 9 - main nozzle;

[0039] 10 - Self - exciting oscillation cavity; 101 - Upper nozzle; 102 - Resonant cavity chamber; 103 - Lower nozzle; 104 - Collision wall; 105 - Sealing groove; 106 - Self - exciting oscillation cavity sealing ring. Specific embodiments

[0040] The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0041] Refer to Figures 1 to 9 As shown, in an embodiment provided by the present invention, a composite impact drilling tool includes a sleeve. Inside the sleeve, a self - exciting oscillation cavity 10, an end cap 4, and a hammer base 1 are sequentially arranged from top to bottom along the length direction. Inside the hammer base 1, an impact hammer 5 and a reversing seat 2 are sequentially arranged. Inside the impact hammer 5, a reversing sleeve 3 is arranged. Inside the reversing seat 2, a main nozzle 9 is arranged. The lower end of the hammer base 1 is connected to a drill bit; the upper end of the sleeve 6 is used to connect to the upper drill string, and a sleeve central hole is provided at the upper end of the sleeve 6; both the end cap 4 and the reversing sleeve 3 are provided with central holes along the axial direction. High - pressure drilling fluid passes through the central flow path composed of the end cap 4, the reversing sleeve 3, and the main nozzle 9; a pressure difference is formed above and below the main nozzle 9, serving as the power source for driving the movement of the impact hammer and the reversing sleeve.

[0042] Further, the self - exciting oscillation cavity 10 and the end cap 4 form an upper axial impact device. The end cap 4 is connected to the hammer base 1. The end cap 4, the impact hammer 5, the hammer base 1, the reversing sleeve 3, the reversing seat 2, and the main nozzle 9 form a lower torsional impact device; there is an upper axial impact device and a lower torsional impact device, and the two are combined and installed inside the sleeve 6.

[0043] Further, the central hole 31 of the reversing sleeve runs through the reversing sleeve 3 vertically up and down, and the drilling fluid can enter the central hole 31 of the reversing sleeve and then flow downward; part of the drilling fluid enters the central hole 31 of the reversing sleeve, and part enters between the impact hammer 5 and the hammer base 1. The drilling fluid entering between the impact hammer 5 and the hammer base 1 can drive the impact hammer 5 to rotate, and then reciprocally impact the hammer base 1, and transmit the impact torque to the hammer base 1, and then through the hammer base 1 to the drill bit.

[0044] Further, a locking ring is provided between the hammer base 1 and the sleeve 6 for axial positioning and installation. The locking ring includes a plurality of sector - shaped locking blocks 7 distributed circumferentially;

[0045] The lower part of the sleeve is connected to the hammer base through splines; a plurality of spline grooves are arranged circumferentially on the inner circle of the sleeve, and a plurality of splines are arranged circumferentially at the corresponding positions on the outer circle of the hammer base. The splines are arranged in the corresponding spline grooves, and the rock - breaking torque of the drill bit is transmitted through spline fitting.

[0046] Furthermore, the bottom of the commutation sleeve 3 has a supporting surface that contacts the supporting surface of the commutation seat 2, and a supporting surface is provided at the top of the commutation sleeve 3 to contact the supporting surface at the lower part of the end cap, so that both the upper and lower ends of the commutation sleeve 3 are restricted radially. During the rotation of the commutation sleeve 3, there is the support of the supporting surface, making it not easy to tilt and preventing the commutation sleeve 3 from jamming during high-speed rotation. At the same time, it can also ensure the accurate relative position relationship between the end cap 4 and the commutation sleeve 3. There are two stepped holes of different sizes under the end cap, a set of large holes and a set of small holes up and down, which are respectively used to straighten and install the impact hammer 5 and the commutation sleeve 3.

[0047] The end cap 4 may have an end cap central hole 43 and a side flow channel 41. The end cap central hole 43 may be coaxially arranged with the commutation sleeve central hole 31, and the drilling fluid flowing through the side flow channel 41 flows to the outside of the end cap 4.

[0048] Furthermore, along the axial direction from top to bottom on the self-excited oscillation cavity 10, there are an upper nozzle 101, a resonance cavity 102, and a lower nozzle 103 in sequence. A collision wall 104 is provided at the outlet end of the resonance cavity 102.

[0049] Furthermore, a self-excited oscillation cavity sealing ring 106 is provided between the self-excited oscillation cavity 10 and the sleeve 6. A sealing groove 105 is provided on the outer wall of the sleeve 6, and the self-excited oscillation cavity sealing ring 106 is arranged in the sealing groove 105.

[0050] Furthermore, a plurality of connection holes 42 are arranged circumferentially at the bottom of the end cap 4. The end cap 4 is fixedly connected to the hammer base 1 by bolts or screws, and the bolts or screws pass through the connection holes 42 to connect with the hammer base 1.

[0051] Furthermore, the nozzle diameter of the main nozzle 9 is smaller than the diameter of the commutation sleeve central hole 31, which plays a role of pressure buildup in the tool, enabling part of the drilling fluid to enter between the impact hammer 5 and the hammer base 1, thereby driving the impact hammer 5 to strike the hammer base 1.

[0052] Furthermore, a plurality of drain grooves 11 are distributed circumferentially on the inner circle of the hammer base 1, and the commutation seat 2 has a convex rib 21 clamped in the drain grooves 11;

[0053] The opposite sides of the convex rib 21 are in contact with the plane of the drain groove 11, enabling the commutation seat 2 to remain in a relatively stationary state with the hammer base 1. When the hammer base 1 rotates, the commutation seat 2 rotates together with the hammer base 1; the commutation sleeve 3 installed in the hammer base 1 is located above the commutation seat 2, and the commutation sleeve 3 has a commutation sleeve central hole 31 for the drilling fluid to flow through.

[0054] Furthermore, the commutation seat 2 is generally installed at the middle position of the hammer base 1, and the hammer base 1 is provided with a step at the bottom of the commutation seat 2 to support the commutation seat 2, so that the commutation seat 2 is stably installed in the hammer base 1.

[0055] Furthermore, a plurality of side flow channels 41 are circumferentially distributed on the side wall of the end cap 4. The side flow channels 41 communicate with the central hole 43 of the end cap. A plurality of second diversion grooves 12 are circumferentially distributed on the outer ring of the hammer base 1. The second diversion grooves 12 communicate with the side flow channels 41. A secondary nozzle 13 is provided at the bottom of the second diversion groove 12. The secondary nozzle 13 communicates with the bottom of the central hole of the hammer base 1.

[0056] On both sides of the inner ring of the hammer base 1, two impact chambers 14 are symmetrically arranged. On both outer sides of the impact hammer 5, two hammer heads 53 are symmetrically provided. The two hammer heads 53 are respectively arranged in the two impact chambers 14. On both sides of each hammer head 53 along the length direction of the impact hammer 5, a plurality of third diversion holes 54 are provided. The third diversion holes 54 communicate with the impact chambers 14. A plurality of first diversion holes 32 are circumferentially distributed on the commutator sleeve 3 along the central hole 31 of the commutator sleeve. The central hole 31 of the commutator sleeve communicates with the third diversion holes 54 through the first diversion holes 32.

[0057] A starting chamber 33 is provided on the outer wall of the commutator sleeve 3. An inner key is provided in the starting chamber 33. A third diversion groove 34 is provided on one side of the starting chamber 33. When the commutator sleeve 3 rotates forward or backward relative to the impact hammer 5, the third diversion holes 54 are aligned and communicated or misaligned and separated from the third diversion groove 34.

[0058] The commutator base 2 is provided with a through groove 22 along the axial direction. The through groove 22 is arranged on both sides of the main nozzle 9.

[0059] A plurality of fourth diversion holes 15 are circumferentially distributed on the inner ring of the hammer base 1. The fourth diversion holes 15 communicate with the second diversion grooves 12. When the commutator sleeve 3 rotates forward or backward relative to the hammer base 1, the fourth diversion holes 15 are aligned and communicated or misaligned and separated from the starting chamber 33.

[0060] Further, when the drilling fluid flows into the end cap 4, part of the drilling fluid flows downward through the central hole 43 of the end cap, the central hole 31 of the reversing sleeve, the reversing seat 2, and the main nozzle 9. Since the outlet diameter of the main nozzle 9 is small, a high pressure is formed in the channel above the outlet of the main nozzle 9. The high-pressure drilling fluid sequentially passes through the side flow channel 41 of the end cap 4, the second diversion groove 12 of the hammer base, and the fourth diversion hole 15 to enter the starting chamber 33, pushing the reversing sleeve 3 to rotate counterclockwise around the axis of the tool, and the impact hammer 5 to rotate clockwise around the axis of the tool. At this time, it is in the non-started state; when the left side of the inner key 51 contacts the side of the starting chamber 33, the two stop rotating, and at this time it is in the started state; then the high-pressure drilling fluid enters the gap between the right side of the hammer head 53 and the side of the impact chamber 14 through the first diversion hole 32 and the third diversion hole 54 on the right side of the hammer head 53. The right side of the hammer head 53 bears high pressure, while the drilling fluid on the left side of the hammer head 53 flows downward through the third diversion hole 54 on the left side of the hammer head 53, the third diversion groove 34, and the through groove 22 of the reversing seat 2. The drilling fluid on the left side of the hammer head 53 is at low pressure. Under the action of the high and low pressure difference on both sides of the hammer head 53, the impact hammer 5 rotates clockwise around the axis of the hammer base 1. At the same time, the impact hammer 5 drives the reversing sleeve 3 to rotate synchronously clockwise through the inner key 51 until the left side of the hammer head 53 hits the inner wall surface of the impact chamber 14. The impact hammer 5 stops rotating and transmits the impact torque to the hammer base 1. At this time, it is the impact moment. Due to the action of inertia, the reversing sleeve 3 continues to rotate clockwise, and the left side of the inner key 51 disengages from the side of the starting chamber 33. The high-pressure drilling fluid sequentially passes through the side flow channel 41 of the end cap 4, the second diversion groove 12, and the fourth diversion hole 15 to enter the cavity formed by the disengagement of the inner key 51 from the starting chamber 33. At the same time, the drilling fluid on the other side of the inner key 51 flows downward through the second diversion hole 52, the drain groove 11, and the through groove 22, causing a low pressure on the other side of the inner key 51. The reversing sleeve 3 continues to rotate clockwise under the combined action of inertia and the high and low pressure difference on both sides of the inner key 51 until the right side of the inner key 51 contacts the side of the starting chamber 33. At this time, it is the reversing reset state. The reversing sleeve 3 completes the reversing function, and the high and low pressures of the drilling fluid are respectively connected to both sides of the hammer head 53 again. The impact hammer 5 and the reversing sleeve 3 rotate counterclockwise synchronously and impact the hammer base 1. This cycle repeats, and the impact hammer 5 continuously impacts the hammer base 1 reciprocally.

[0061] Further, the axial impact device of the composite impact drilling tool includes: a self-excited oscillation chamber installed at the upper part and an end cap shared with the torsional impact device. The axial impact device utilizes the hydraulic pulse oscillation generated by the mud in the drill string passing through the upper self-excited oscillation chamber to act on the end cap. The end cap has a pulsed axial force. The end cap is fixedly connected to the hammer base of the torsional impact device. Therefore, the pulsed axial force acts on the hammer base and is transmitted to the drill bit, applying a periodic axial impact load to the drill bit.

[0062] The self-excited oscillation chamber adopts different structures, which can generate hydraulic pulse oscillations with different frequencies and different pressure amplitudes.

[0063] The described hammer base simultaneously bears the axial impact force generated by the self-excited oscillation chamber in the axial impact device and the torsional impact force generated by the impact hammer in the torsional impact device.

[0064] The material of the self-excited oscillation chamber is made of erosion-resistant cemented carbide, which can improve the service life.

[0065] The working principle of the present invention: The embodiment of the present invention provides a composite impact drilling tool, which is composed of an upper axial impact device and a lower torsional impact device.

[0066] See Figure 1 As shown, an embodiment of a composite impact drilling tool of the present invention is schematically shown. This embodiment includes a hammer base 1, a reversing seat 2, a reversing sleeve 3, an end cap 4, an impact hammer 5, a sleeve 6, a locking block 7, a sealing ring 8, a main nozzle 9, and a self-excited oscillation chamber 10.

[0067] See Figure 1 、 Figure 2 、and Figure 3 As shown, a self-excited oscillation chamber 10 is installed above the sleeve 6. The self-excited oscillation chamber 10 has an upper nozzle 101, a resonance chamber 102, a lower nozzle 103, a collision wall 104, a sealing groove 105, and a self-excited oscillation chamber sealing ring 106. The end cap 4 is installed below the self-excited oscillation chamber 10, and the end cap 4 is fixedly connected to the hammer base 1 through bolts and connection holes 42. Further, the material of the self-excited oscillation chamber 10 is cemented carbide, which can improve the erosion resistance and thus the service life of the self-excited oscillation chamber.

[0068] See Figure 1 、 Figure 3 、 Figure 4 and Figure 6As shown, the lower end of the hammer base 1 has a thread for connecting with the drill bit, and the upper end of the hammer base 1 is fixedly connected to the end cap 4 through screws and the end cap connection hole 42. The hammer base 1 has a liquid discharge groove 11 located inside it. In this embodiment, the cross-section of the liquid discharge groove 11 is arc-shaped. In other embodiments, the cross-section of the liquid discharge groove 11 can also be rectangular or other shapes; the reversing seat 2 is generally installed at the middle position of the hammer base 1, and the hammer base 1 is provided with a step at the bottom of the reversing seat 2 to support the reversing seat 2, so that the reversing seat 2 is stably installed in the hammer base 1, and the reversing seat 2 has a convex rib 21 clamped in the liquid discharge groove 11. In this embodiment, the opposite sides of the convex rib 21 are in plane contact with the liquid discharge groove 11, so that the reversing seat 2 can remain relatively stationary with the hammer base 1. When the hammer base 1 rotates, the reversing seat 2 rotates with the hammer base 1; the reversing sleeve 3 installed in the hammer base 1 is located above the reversing seat 2. The reversing sleeve 3 has a reversing sleeve central hole 31 for the drilling fluid to flow through. In this embodiment, the reversing sleeve central hole 31 runs through the reversing sleeve 3 up and down, and the drilling fluid can enter the reversing sleeve central hole 31 and then flow downward; the bottom of the reversing sleeve 3 has a supporting surface in contact with the supporting surface of the reversing seat, and a supporting surface is provided at the top of the reversing sleeve 3 in contact with the lower supporting surface of the end cap, so that both the upper and lower ends of the reversing sleeve 3 are restricted radially. During the rotation process of the reversing sleeve 3, there is the support of the supporting surface, and it is not easy to tilt, preventing the reversing sleeve 3 from jamming during high-speed rotation. At the same time, it can also ensure the accurate relative position relationship between the end cap 4 and the reversing sleeve 3.

[0069] See Figure 1 As shown, in some embodiments, the compound impact drilling tool may further include an impact hammer 5 located between the hammer base 1 and the reversing sleeve 3. Part of the drilling fluid enters the reversing sleeve central hole 31, and part enters between the impact hammer 5 and the hammer base 1. The drilling fluid entering between the impact hammer 5 and the hammer base 1 can drive the impact hammer 5 to rotate, and then reciprocally impact the hammer base 1, and transmit the impact torque to the hammer base 1, and then transmit it to the drill bit through the hammer base 1.

[0070] See Figure 1 As shown, in this embodiment, by installing a main nozzle 9 at the center of the reversing seat 2, the main nozzle 9 can be fixed to the reversing seat 2 by threads or snap rings or other means. A main nozzle sealing ring can also be provided between the main nozzle 9 and the reversing seat 2. At the same time, the nozzle diameter is smaller than the diameter of the reversing sleeve central hole 31, which plays a role of pressure build-up in the tool, so that part of the drilling fluid can enter between the impact hammer 5 and the hammer base 1, thereby driving the impact hammer 5 to impact the hammer base 1.

[0071] See Figure 1 、 Figure 3 、 Figure 4 and Figure 6As shown, further, the end cap 4 may have an end cap central hole 43 and a side flow channel 41. The end cap central hole 43 may be coaxially arranged with the commutation sleeve central hole 31. The drilling fluid flowing through the side flow channel 41 flows to the outside of the end cap 4. In this embodiment, there are 4 side flow channels 41. At the same time, the hammer base 1 may also be provided with a second diversion groove 12 corresponding to the side flow channel 41. When the end cap 4 is fixed to the hammer base 1, the side flow channel 41 can communicate with the corresponding second diversion groove 12. After the drilling fluid flows to the outside of the end cap 4 through the side flow channel 41, it can enter the second diversion groove 12. A sub-nozzle 13 may be provided at the bottom of the second diversion groove 12. The sub-nozzle 13 communicates with the central hole at the bottom of the hammer base 1 and is used for allowing the sediment deposited at the bottom of the second diversion groove 12 to pass through.

[0072] See Figure 1 and Figure 6 As shown, in this embodiment, two impact chambers 14 are provided on the hammer base 1. The cross-section of the impact chamber 14 is preferably fan-shaped. Two hammer heads 53 are correspondingly arranged on the outside of the impact hammer 5. Two third diversion holes 54 are arranged vertically on the left side of each hammer head 53, and two third diversion holes 54 are also arranged vertically on the right side of each hammer head 53. Part of the drilling fluid can enter the gap between one side of the hammer head 53 and the impact chamber 14 through the third diversion hole 54 on one side of the hammer head 53, driving the hammer head 53 to rotate towards the other side and impact the side wall of the impact chamber 14. Specifically, the drilling fluid entering the commutation sleeve central hole 31 can enter the third diversion hole 54 through the first diversion hole 32, and then enter the gap between one side of the hammer head 53 and the inner wall surface of the impact chamber 14 through the third diversion hole 54. At the same time, in this embodiment, the commutation sleeve 3 is provided with a third diversion groove 34 on one side of the starting chamber 33. When the drilling fluid enters the gap between one side of the hammer head 53 and the impact chamber 14 through the third diversion hole 54 on one side of the hammer head 53, the drilling fluid between the other side of the hammer head 53 and the impact chamber 14 can enter the third diversion groove 34 through the third diversion hole 54 on the other side of the hammer head 53, and then flow out from the lower end of the third diversion groove 34, so that a high-pressure state is presented between one side of the hammer head 53 and the impact chamber 14, and a low-pressure state is presented between the other side of the hammer head 53 and the impact chamber 14. Under the action of the high and low pressure difference on both sides, the impact hammer 5 rotates around the axis of the hammer base 1. At the same time, the impact hammer 5 drives the commutation sleeve 3 to rotate synchronously through the internal key 51 until the other side of the hammer head 53 impacts the inner wall surface of the impact chamber 14, and the impact hammer 5 stops rotating and transmits the impact torque to the hammer base 1.

[0073] See Figure 1 As shown, in some embodiments, the bottom of the impact hammer 5 has a guiding surface that fits with the guiding surface at the top of the commutation seat, ensuring that the impact hammer 5 is not easily tilted during the high-speed rotation process. At the same time, the top of the impact hammer 5 has a guiding surface that contacts the guiding surface at the bottom of the end cap 4, providing a radial guiding function for the impact hammer 5 to prevent the impact hammer 5 from jamming during rotation.

[0074] See Figure 1 and Figure 5 As shown, in some alternative embodiments, a sleeve 6 may be sleeved outside the hammer base 1. The upper end of the sleeve 6 is provided with an external thread for connecting to the drill string. Further, a plurality of splines 18 are protruded outside the hammer base 1. In this embodiment, the number of splines is preferably 4, so that the hammer base 1 and the sleeve 6 are meshed with each other through the splines, for transmitting the weight-on-bit and torque load of the drill string to the hammer base 1 through the sleeve 6, and then the hammer base 1 transmits the weight-on-bit and torque load of the drill string and the impact load generated by the tool itself to the drill bit.

[0075] See Figure 1 As shown, further, a first locking groove 62 may be provided inside the sleeve 6. The first locking groove 62 is circular along the circumferential direction of the sleeve 6. A circular second locking groove 16 corresponding to the first locking groove 62 is provided outside the hammer base 1, and the second locking groove 16 and the first locking groove 62 together form a locking cavity. A plurality of locking blocks 7 are sequentially installed in the locking cavity until the locking cavity is filled; the left side and the right side of the locking block 7 may form a fan-shaped angle, and the inner side and the outer side of the locking block 7 are cylindrical surfaces, and the upper side and the lower side of the locking block 7 are flat surfaces or other curved surfaces. When the drill string is lifted, the sleeve 6 drives the hammer base 1 and the drill bit below to rise through the locking block 7. The contact surfaces of the locking block 7 with the sleeve 6 and the hammer base 1 are flat surfaces or other curved surfaces. If the conventional steel ball locking method is adopted, and the steel ball locking is point contact, in the embodiment of the present invention, the locking block 7 is in surface contact with both the sleeve 6 and the hammer base 1. The sleeve 6 and the hammer base 1 are locked through the locking block 7, so that the whole tool can bear a large pulling force and has high safety.

[0076] Further, a sealing groove 17 may be provided outside the hammer base 1, and a sealing ring 8 is installed in the sealing groove 17. The sealing ring 8 is used to seal between the lower part of the hammer base 1 and the sleeve 6.

[0077] See Figure 1 、 Figure 2 、 Figures 6 to 9 As shown, the working process of the compound impact drilling tool provided by the embodiment of the present invention is as follows: When the drilling fluid flows from top to bottom through the sleeve central hole 61 at the upper end of the sleeve 6 into the self-excited oscillation chamber 10, the drilling fluid enters the resonance chamber 102 through the upper nozzle 101 of the self-excited oscillation chamber. Part of the drilling fluid collides with the collision wall 104 and flows back in the resonance chamber 102, forming a jet flow with periodic pressure pulsation in the resonance chamber 102. The jet flow sprays out from the lower nozzle 103. The drilling fluid with periodic pressure pulsation acts on the end cap 4 to form an axial impact vibration. The end cap 4 is connected to the hammer base 1, and the hammer base 1 is connected to the drill bit. The axial impact vibration generated by the self-excited oscillation chamber 10 is transmitted to the drill bit by the hammer base 1.

[0078] When the drilling fluid flows into the end cap 4, part of the drilling fluid flows downward through the central hole 43 of the end cap, the central hole 31 of the reversing sleeve, the reversing seat 2 and the main nozzle 9. Since the outlet diameter of the main nozzle 9 is small, a high pressure is formed in the channel above the outlet of the main nozzle 9. The high-pressure drilling fluid sequentially passes through the side flow channel 41 of the end cap 4, the second diversion groove 12 of the hammer base, and the fourth diversion hole 15 to enter the starting chamber 33, pushing the reversing sleeve 3 to rotate counterclockwise around the axis of the tool, and the impact hammer 5 to rotate clockwise around the axis of the tool. At this time, it is in the non-start state; when the left side of the inner key 51 contacts the side of the starting chamber 33, the two stop rotating, and at this time it is in the start state; then the high-pressure drilling fluid enters the gap between the right side of the hammer head 53 and the side of the impact chamber 14 through the first diversion hole 32 and the third diversion hole 54 on the right side of the hammer head 53. The right side of the hammer head 53 is under high pressure, while the drilling fluid on the left side of the hammer head 53 flows downward through the third diversion hole 54 on the left side of the hammer head 53, the third diversion groove 34, and the through groove 22 of the reversing seat 2. The drilling fluid on the left side of the hammer head 53 is at low pressure. Under the action of the high and low pressure difference on both sides of the hammer head 53, the impact hammer 5 rotates clockwise around the axis of the hammer base 1. At the same time, the impact hammer 5 drives the reversing sleeve 3 to rotate synchronously clockwise through the inner key 51 until the left side of the hammer head 53 hits the inner wall surface of the impact chamber 14, and the impact hammer 5 stops rotating and transmits the impact torque to the hammer base 1. At this time, it is the impact moment. Due to the action of inertia, the reversing sleeve 3 continues to rotate clockwise, and the left side of the inner key 51 disengages from the side of the starting chamber 33. The high-pressure drilling fluid sequentially passes through the side flow channel 41 of the end cap 4, the second diversion groove 12, and the fourth diversion hole 15 to enter the cavity formed by the disengagement of the inner key 51 from the starting chamber 33. At the same time, the drilling fluid on the other side of the inner key 51 flows downward through the second diversion hole 52, the drain groove 11, and the through groove 22, making the other side of the inner key 51 at low pressure. The reversing sleeve 3 continues to rotate clockwise under the combined action of inertia and the high and low pressure difference on both sides of the inner key 51 until the right side of the inner key 51 contacts the side of the starting chamber 33. At this time, it is in the reversing reset state. The reversing sleeve 3 completes the reversing function, and the high and low pressures of the drilling fluid are respectively connected to both sides of the hammer head 53 again. The impact hammer 5 and the reversing sleeve 3 rotate counterclockwise synchronously and hit the hammer base 1. This cycle repeats, and the impact hammer 5 continuously impacts the hammer base 1 reciprocally.

[0079] The hammer base 1 is subjected to both axial impact and torsional impact. The combined impact force is transmitted to the drill bit. The axial impact can increase the depth of the drill bit penetrating into the rock and the rock-breaking efficiency, and the torsional impact reduces the stick-slip vibration of the drill bit. The two impacts work together to improve the rock-breaking efficiency of the drill bit and protect the drill string.

[0080] The above are only the preferred embodiments of the present invention. Of course, the scope of the rights of the present invention cannot be limited by this. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the protection scope of the present invention.

Claims

1. A composite impact drilling tool, characterized in that, It includes a sleeve. Inside the sleeve, a self-excited oscillation chamber (10), an end cap (4), and a hammer base (1) are sequentially arranged from top to bottom along the length direction. Inside the hammer base (1), an impact hammer (5) and a commutation seat (2) are sequentially arranged. Inside the impact hammer (5), a commutation sleeve (3) is arranged. Inside the commutation seat (2), a main nozzle (9) is arranged. The lower end of the hammer base (1) is connected to a drill bit; both the end cap (4) and the commutation sleeve (3) are provided with central holes along the axial direction, and high-pressure drilling fluid passes through the central flow path composed of the central holes of the end cap (4), the commutation sleeve (3), and the main nozzle (9). The central hole (31) of the commutation sleeve runs through the commutation sleeve (3) vertically. Drilling fluid enters the central hole (31) of the commutation sleeve and then flows downward; part of the drilling fluid enters the central hole (31) of the commutation sleeve, and part enters between the impact hammer (5) and the hammer base (1). The drilling fluid entering between the impact hammer (5) and the hammer base (1) can drive the impact hammer (5) to rotate, and then reciprocally strike the hammer base (1), and transmit the impact torque to the hammer base (1), and then through the hammer base (1) to the drill bit. A plurality of side flow paths (41) are circumferentially distributed on the side wall of the end cap (4). The side flow paths (41) communicate with the central hole (43) of the end cap. A plurality of second diversion grooves (12) are circumferentially distributed on the outer ring of the hammer base (1). The second diversion grooves (12) communicate with the side flow paths (41). A secondary nozzle (13) is provided at the bottom of the second diversion groove (12), and the secondary nozzle (13) communicates with the bottom of the central hole of the hammer base (1). An impact chamber (14) is arranged on the inner ring of the hammer base (1). A hammer head (53) is arranged outside the impact hammer (5). The hammer head (53) is arranged inside the impact chamber (14). Third diversion holes (54) are provided on both sides of the hammer head (53) along the length direction of the impact hammer (5), and the third diversion holes (54) communicate with the impact chamber (14); a plurality of first diversion holes (32) are circumferentially distributed on the commutation sleeve (3) along the central hole (31) of the commutation sleeve. The central hole (31) of the commutation sleeve communicates with the third diversion holes (54) through the first diversion holes (32). An activation chamber (33) is arranged on the outer wall of the commutation sleeve (3). An inner key is arranged inside the activation chamber (33). A third diversion groove (34) is arranged on one side of the activation chamber (33). When the commutation sleeve (3) rotates forward or backward relative to the impact hammer (5), the third diversion holes (54) are in alignment and communication or misaligned and separated from the third diversion groove (34). The commutation seat (2) is provided with a through groove (22) along the axial direction. A plurality of fourth diversion holes (15) are circumferentially distributed on the inner ring of the hammer base (1). The fourth diversion holes (15) communicate with the second diversion grooves (12). When the commutation sleeve (3) rotates forward or backward relative to the hammer base (1), the fourth diversion holes (15) are in alignment and communication or misaligned and separated from the activation chamber (33).

2. The composite impact drilling tool according to claim 1, wherein, A locking ring is arranged between the hammer base (1) and the sleeve (6) for axial positioning and installation. The locking ring includes a plurality of sector-shaped locking blocks (7) circumferentially distributed; the lower part of the sleeve is connected to the hammer base through a spline, and the rock-breaking torque of the drill bit is transmitted through spline fitting.

3. The composite impact drilling tool according to claim 1, characterized in that, The bottom of the reversing sleeve (3) has a supporting surface that contacts the supporting surface of the reversing seat (2). A supporting surface is provided at the top of the reversing sleeve (3) to contact the supporting surface at the lower part of the end cover, so that both the upper and lower ends of the reversing sleeve (3) are restricted radially, enabling the reversing sleeve (3) to have the support of the supporting surface during rotation. There are two stepped holes of different sizes under the end cover, a set of upper large holes and a set of lower small holes, which are respectively used to correctly position and install the impact hammer (5) and the reversing sleeve (3).

4. The composite impact drilling tool according to claim 1, characterized in that Axially from top to bottom along the self-excited oscillation chamber (10), there are an upper nozzle (101), a resonant cavity chamber (102), and a lower nozzle (103) in sequence. A collision wall (104) is provided at the outlet end of the resonant cavity chamber (102).

5. The composite impact drilling tool according to claim 1, characterized in that, A plurality of connection holes (42) are arranged circumferentially at the bottom of the end cover (4). The end cover (4) is fixedly connected to the hammer base (1) by bolts or screws, and the bolts or screws pass through the connection holes (42) to connect with the hammer base (1).

6. The composite impact drilling tool according to claim 1, wherein, The nozzle diameter of the main nozzle (9) is smaller than the diameter of the central hole (31) of the reversing sleeve.

7. The compound impact drilling tool according to claim 1, wherein A plurality of drain grooves (11) are distributed circumferentially along the inner circle of the hammer base (1). The reversing seat (2) has a convex rib (21) that is clamped in the drain groove (11). The two opposite sides of the convex rib (21) are in plane contact with the drain groove (11), enabling the reversing seat (2) to remain relatively stationary with respect to the hammer base (1). When the hammer base (1) rotates, the reversing seat (2) rotates together with the hammer base (1). The reversing sleeve (3) installed in the hammer base (1) is located above the reversing seat (2), and the reversing sleeve (3) has a central hole (31) of the reversing sleeve for the circulation of drilling fluid.

8. The composite impact drilling tool according to claim 1, characterized in that, When the drilling fluid flows into the end cap (4), part of the drilling fluid flows downward through the central hole (43) of the end cap, the central hole (31) of the reversing sleeve, the reversing seat (2), and the main nozzle (9). Since the outlet diameter of the main nozzle (9) is small, a high pressure is formed in the channel above the outlet of the main nozzle (9). The high-pressure drilling fluid sequentially passes through the side flow channel (41) of the end cap (4), the second diversion groove (12) of the hammer seat, and the fourth diversion hole (15) to enter the starting chamber (33), pushing the reversing sleeve (3) to rotate counterclockwise around the axis of the tool, and the impact hammer (5) to rotate clockwise around the axis of the tool. At this time, it is in the non-started state; when the left side of the inner key (51) contacts the side of the starting chamber (33), both of them stop rotating, and at this time, it is in the started state; then the high-pressure drilling fluid enters the gap between the right side of the hammer head (53) and the side of the impact chamber (14) through the first diversion hole (32) and the third diversion hole (54) on the right side of the hammer head (53). The right side of the hammer head (53) bears high pressure, while the drilling fluid on the left side of the hammer head (53) flows downward through the third diversion hole (54) on the left side of the hammer head (53), the third diversion groove (34), and the through groove (22) of the reversing seat (2). The drilling fluid on the left side of the hammer head (53) is at low pressure. Under the action of the high and low pressure difference on both sides of the hammer head (53), the impact hammer (5) rotates clockwise around the axis of the hammer seat (1). At the same time, the impact hammer (5) drives the reversing sleeve (3) to rotate synchronously clockwise through the inner key (51) until the left side of the hammer head (53) impacts the inner wall surface of the impact chamber (14), and the impact hammer (5) stops rotating and transmits the impact torque to the hammer seat (1). At this time, it is the impact moment. Due to the action of inertia, the reversing sleeve (3) continues to rotate clockwise, the left side of the inner key (51) disengages from the side of the starting chamber (33), and the high-pressure drilling fluid sequentially passes through the side flow channel (41) of the end cap (4), the second diversion groove (12), and the fourth diversion hole (15) to enter the cavity formed by the disengagement of the inner key (51) from the starting chamber (33). At the same time, the drilling fluid on the other side of the inner key (51) flows downward through the second diversion hole (52), the drain groove (11), and the through groove (22), making the other side of the inner key (51) at low pressure. The reversing sleeve (3) continues to rotate clockwise under the combined action of inertia and the high and low pressure difference on both sides of the inner key (51) until the right side of the inner key (51) contacts the side of the starting chamber (33). At this time, it is in the reversing reset state, the reversing sleeve (3) completes the reversing function, the high and low pressures of the drilling fluid are respectively connected to both sides of the hammer head (53), the impact hammer (5) and the reversing sleeve (3) rotate counterclockwise synchronously and impact the hammer seat (1). This cycle repeats, and the impact hammer (5) continuously impacts the hammer seat (1) reciprocally.

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