Hydraulic impact oscillation drilling tool

Abstract

The invention provides a hydraulic impact oscillation drilling tool which comprises a shell, a pulse generating mechanism, a driving mechanism arranged on the downstream of the pulse generating mechanism, a pulse driving mechanism arranged on the downstream of the pulse generating mechanism, and a driving mechanism arranged on the downstream of the pulse generating mechanism, and the pulse generating mechanism comprises a static valve disc abutting against the inner wall face of the shell and a movable valve disc abutting against the lower end face of the static valve disc. The anti-falling device comprises an anti-falling rod, a fastener and a screw, the fastener is arranged between the anti-falling rod and the movable valve disc, the screw is arranged on the downstream of the anti-falling rod, a stator and a rotor are arranged on the screw, the free end of the anti-falling rod is fixedly connected with the rotor, and the rotor, the anti-falling rod and the movable valve disc are coaxially arranged. The pulse generating mechanism is driven by the surplus energy of the screw for driving the drill bit to generate the pressure pulse, so that the drilling tool generates periodic mild vibration, the friction resistance of a shaft bottom drilling tool assembly close to the drill bit is reduced, and bit pressure transmission is improved.

Description

Technical Field

[0001] The present invention relates to the field of oil drilling, and particularly to a hydraulic impact oscillation drill tool. Background Art

[0002] In the drilling of extended reach wells and horizontal wells, due to the large well inclination angle, most of the self-weight of the drill string in the large well-inclination section will press against the wellbore wall. Therefore, the friction between the pipe string and the wellbore is relatively large, resulting in increased drag and torque, and the weight on bit transmitted to the bit is discontinuous or limited. In addition, it is difficult to feed in only relying on the weight of the drill tool in the vertical section, and it is difficult to control the tool face. The length of the horizontal section drilled is limited and the mechanical drilling speed is relatively low.

[0003] Currently, pressure pulse generating tools such as hydraulic oscillators are introduced into the downhole pipe string, and pressure pulses are generated by periodically changing the fluid flow area. These pressure pulses act on the supporting axial vibration generating tools, so as to make the driving drill tool generate axial creeping, reduce the friction coefficient between the pipe string and the wellbore wall during sliding drilling, reduce the friction resistance of the pipe string at the same time, eliminate the drill string drag phenomenon, and then improve the weight on bit transmission effect and the directional drilling efficiency.

[0004] The hydraulic oscillators in the prior art require a dedicated motor drive, have a relatively high pressure drop, and considering the vibration superposition of the positive displacement motor and the hydraulic oscillator during traditional sliding orientation on the vibration of the orientation instrument, generally, the placement position of the hydraulic oscillator is relatively far from the bit, so that the friction resistance near the bit cannot be reduced.

[0005] Therefore, in this field, it is desired to provide a hydraulic impact oscillation drill tool to solve the above technical problems. Summary of the Invention

[0006] The object of the present invention is to provide a hydraulic impact oscillation drill tool, which can utilize the surplus energy of the positive displacement motor driving the bit to drive the pulse generating mechanism to generate pressure pulses, so that the drill tool generates periodic gentle vibrations, thereby reducing the friction resistance of the bottom hole assembly near the bit, improving the weight on bit transmission, and increasing the mechanical drilling speed and the extended reach ability of extended reach wells and horizontal wells.

[0007] According to the present invention, there is provided a hydraulic impact oscillation drill tool, including a housing,

[0008] a pulse generating mechanism, which includes a static valve plate abutting against the inner wall surface of the housing and a dynamic valve plate abutting against the lower end surface of the static valve plate,

[0009] a driving mechanism arranged downstream of the pulse generating mechanism, which includes a drop prevention rod, a fastener arranged between the drop prevention rod and the dynamic valve plate, and a positive displacement motor arranged downstream of the drop prevention rod. A stator and a rotor are arranged on the positive displacement motor, and the free end of the drop prevention rod is fixedly connected to the rotor.

[0010] Wherein, the rotor, the anti-falling rod and the movable valve disc are coaxially arranged.

[0011] The rotor is configured to be capable of making a planetary motion relative to the stator, so that the movable valve disc moves on the static valve disc to change the flow area of the drilling fluid from the static valve disc to the movable valve disc.

[0012] In one embodiment, an eccentric hole allowing the drilling fluid to pass through is provided on the static valve disc, and the eccentricity of the eccentric hole is the same as the eccentricity of the rotor relative to the stator.

[0013] In one embodiment, a through hole having the same aperture as that of the eccentric hole is provided on the movable valve disc.

[0014] The movable valve disc is configured to be capable of periodically changing the overlapping area between the through hole and the eccentric hole under the action of the rotor.

[0015] In one embodiment, the static valve disc includes a static valve disc seat and a static valve disc sleeve forming an interference fit with the static valve disc seat.

[0016] The hydraulic impact oscillation drill tool further includes a splash-proof sleeve hermetically connected to the inner peripheral surface of the housing through a spline, and a gear sleeve provided on the upper end surface of the splash-proof sleeve and configured to be embedded into the static valve disc seat.

[0017] In one embodiment, the movable valve disc includes a movable valve disc seat, and a plurality of water holes are circumferentially and spacedly arranged along the movable valve disc seat, wherein the water holes are axially within the range of the splash-proof sleeve.

[0018] In one embodiment, the movable valve disc further includes a movable valve disc sleeve forming an interference fit with the movable valve disc seat, the diameter of the movable valve disc sleeve is smaller than the diameter of the static valve disc sleeve, and the movable valve disc sleeve is circumferentially within the range of the static valve disc sleeve.

[0019] In one embodiment, a bypass hole concentrically arranged with the eccentric hole and configured to be a partial arc structure is provided on the static valve disc, and the inner diameter of the bypass hole is not less than the outer diameter of the movable valve disc sleeve.

[0020] In one embodiment, the fastener includes a first fixing member configured to be an octagonal structure, and a through groove extending axially upward and adapted to the first fixing member is formed at the joint of the movable valve disc seat and the fastener to allow the anti-falling rod to move synchronously with the movable valve disc.

[0021] In one embodiment, the fastener further includes a second fixing member having an octagonal structure disposed between the first fixing member and the anti-falling rod, and the volume of the second fixing member is larger than that of the first fixing member.

[0022] In one embodiment, the driving mechanism further includes an octagonal pad sleeved outside the anti-falling rod and adapted to the second fixing member.

[0023] In one embodiment, the hydraulic impact oscillator further includes an energy conversion mechanism disposed upstream of the pulse generating mechanism. The energy conversion mechanism includes a cylinder block, an impact main shaft concentrically arranged inside the cylinder block, a piston disposed in the annulus between the cylinder block and the impact main shaft, and a joint disposed between the cylinder block and the impact main shaft. Wherein, sealing rings are provided between the piston and both the cylinder block and the impact main shaft.

[0024] In one embodiment, the energy conversion mechanism further includes an anti-falling member radially disposed outside the impact main shaft and used to limit the movement stroke of the piston.

[0025] Compared with the prior art, the advantages of the present invention are as follows:

[0026] Firstly, the present invention utilizes the surplus energy of the screw driving the drill bit to drive the pulse generating mechanism to generate pressure pulses, causing the drill to produce periodic gentle vibrations, thereby reducing the friction resistance of the bottom hole assembly near the bit, improving the drill pressure transmission, increasing the mechanical drilling rate and the extension ability of extended reach wells and horizontal wells, and further solving the problem of difficult tool face control.

[0027] Specifically, the moving valve disc sleeve in the present invention can rotate periodically within the range of the static valve disc sleeve under the driving action of the rotor of the screw, the anti-falling rod and the moving valve disc, and rely on the change in the overlapping area between the through hole of the moving valve disc and the eccentric hole of the static valve disc, so that the flow area of the drilling fluid from the static valve disc to the moving valve disc changes periodically to generate high-frequency pressure pulses, and the pressure pulses can cause the vibration of the lower drill string assembly (not shown) to prevent sticking.

[0028] Secondly, the present invention can also generate hydraulic impact on the bottom hole bit, which is beneficial to the drill pressure transmission during sliding directional drilling, so as to achieve the purpose of increasing the rock breaking energy and improving the directional efficiency and drilling speed.

[0029] Specifically, when the hydraulic impact oscillator is working, due to the pressure pulse generated by the pulse generating mechanism, the internal and external pressure difference acting on the piston will also pulsate, thereby realizing axial hydraulic impact and improving the rock breaking efficiency of the bit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be described in detail below with reference to the drawings. In the drawings:

[0031] Figure 1 Schematically shows the structure of the hydraulic impact oscillation drill according to the present invention;

[0032] Figure 2 is Figure 1 a partial cross-sectional view of, which shows the connection relationship between the pulse generating mechanism and the driving mechanism;

[0033] Figure 3 is Figure 1 a partial cross-sectional view of, which schematically shows the structure of the energy conversion mechanism;

[0034] Figure 4 is a cross-sectional view of the static valve plate in the hydraulic impact oscillation drill according to the present invention;

[0035] Figure 5 is a cross-sectional view of the moving valve plate in the hydraulic impact oscillation drill according to the present invention;

[0036] Figure 6 Schematically shows the structure of the splash guard in the hydraulic impact oscillation drill according to the present invention;

[0037] Figure 7 is a schematic diagram of the periodic change of the flow area when the moving valve plate makes a planetary motion with the screw rotor.

[0038] In the drawings, the same components are denoted by the same reference numerals. The drawings are not drawn to actual scale. Detailed Description of the Invention

[0039] In order to make the technical solutions and advantages of the present invention clearer and more understandable, the following further describes the exemplary embodiments of the present invention in conjunction with the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than an exhaustive list of all embodiments. And without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0040] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0041] In the present invention, unless otherwise clearly defined and limited, the terms "mounted", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components.

[0042] For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] The present invention will be further described below with reference to the accompanying drawings.

[0044] Figure 1 Schematically shows the structure of the hydraulic impact oscillation drill tool 100 according to the present invention;

[0045] Figure 2 is Figure 1 a partial cross-sectional view of, which shows the connection relationship between the pulse generating mechanism 20 and the driving mechanism 30;

[0046] Figure 3 is Figure 1 a partial cross-sectional view of, which schematically shows the structure of the energy conversion mechanism 60;

[0047] Figure 4 is a cross-sectional view of the static valve plate 21 in the hydraulic impact oscillation drill tool according to the present invention;

[0048] Figure 5 is a cross-sectional view of the moving valve plate 22 in the hydraulic impact oscillation drill tool according to the present invention;

[0049] Figure 6 Schematically shows the structure of the splash guard 41 in the hydraulic impact oscillation drill tool 100 according to the present invention;

[0050] Figure 7 is a schematic diagram of the periodic change of the flow area when the moving valve plate 22 in the hydraulic impact oscillation drill tool 100 makes a planetary motion along with the screw rotor.

[0051] As Figure 1 shown, the hydraulic impact oscillation drill tool 100 according to the present invention includes a housing 10, a pulse generating mechanism 20, a driving mechanism 30, and an energy conversion mechanism 60. Among them, the pulse generating mechanism 20 and the driving mechanism 30 are both arranged in the housing 10, and the driving mechanism 30 is located downstream of the pulse generating mechanism 20. The energy conversion mechanism 60 is arranged upstream of the housing 10 and is threadedly connected to the upper end surface of the housing 10, so as to smoothly guide the drilling fluid from the upstream into the housing 10.

[0052] In one embodiment, as Figure 2 shown, the pulse generating mechanism 20 includes a static valve plate 21. The outer wall surface of the static valve plate 21 is radially abutted against the inner wall surface of the housing 10, and the static valve plate 21 can move synchronously with the housing 10 under the action of the splash guard 41 (introduced below), and the content is introduced below.

[0053] In one embodiment, as Figure 2 shown, the pulse generating mechanism 20 further includes a movable valve disc 22 downstream of the static valve disc 21. In the present invention, there is a gap between the static valve disc 21 and the movable valve disc 22 in the initial state.

[0054] Preferably, during operation, the static valve disc 21 can move downward under the action of hydraulic pressure, so as to promote the lower end surface of the static valve disc 21 to axially abut against the upper end surface of the movable valve disc 22, which helps to achieve the purpose of periodically adjusting the flow area of the drilling fluid from the static valve disc 21 to the movable valve disc 22 in the subsequent process.

[0055] In one embodiment, as Figure 2 shown, the driving mechanism 30 includes a drop prevention rod 31, a fastener disposed between the drop prevention rod 31 and the movable valve disc 22, and a screw rod 33 downstream of the drop prevention rod 31. Among them, a stator (not shown) and a rotor (not shown) are provided on the screw rod 33, and the rotor of the screw rod 33 can perform a planetary motion relative to the stator of the screw rod 33.

[0056] Preferably, the free end of the drop prevention rod 31 can be fixedly connected to the rotor of the screw rod 33, so that the drop prevention rod 31 can perform a planetary motion relative to the stator under the driving action of the rotor. In addition, since the drop prevention rod 31 and the movable valve disc 22 are fixedly connected through a fastener, it is ensured that the two can move synchronously, that is, the movable valve disc 22 can perform a planetary motion relative to the stator under the driving action of the drop prevention rod 31 and the rotor.

[0057] In one embodiment, the rotor of the screw rod 33, the drop prevention rod 31 and the movable valve disc 22 are coaxially arranged. In this way, the drop prevention rod 31 and the movable valve disc 22 can perform a planetary motion relative to the stator in the housing 10 following the rotor.

[0058] According to a specific embodiment of the present invention, the rotor of the screw rod 33 is configured to be able to perform a planetary motion relative to the stator of the screw rod 33, so that the movable valve disc 22 moves on the static valve disc 21 to change the flow area of the drilling fluid from the static valve disc 21 to the movable valve disc 22, thereby generating a pressure pulse and acting on the drill string assembly (not shown) to generate a periodic gentle vibration, so as to achieve the effect of reducing the friction resistance of the drill string.

[0059] In addition, since the pressure pulses generated by the pulse generating mechanism 20 and the driving mechanism 30 can also act on the piston 63 (introduced below) in the energy conversion mechanism 60, it can be converted into axial impact energy to further improve the rock breaking efficiency and speed of the drill bit (not shown).

[0060] In one embodiment, as Figure 7As shown, an eccentric hole 201 allowing drilling fluid to pass through is provided on the static valve plate 21. Preferably, the eccentricity of the eccentric hole 201 is the same as the eccentricity of the rotor of the screw 33 relative to the stator of the screw 33, so that it can be more easily matched with the through hole 203 (introduced below) on the moving valve plate 22.

[0061] In one embodiment, as Figure 7 shown, a through hole 203 having the same aperture as the eccentric hole 201 is provided on the moving valve plate 22. It is easy to understand that the through hole 203 is located at the center of the moving valve plate 22. Since the moving valve plate 22 can rotate relative to the static valve plate 21, and the revolution radius of the moving valve plate 22 is the eccentricity of the rotor of the screw 33, and the eccentricity of the rotor of the screw 33 is the same as the eccentricity of the eccentric hole 201 of the static valve plate 21, therefore, the moving valve plate 22 and the rotor of the screw 33 revolve and rotate synchronously relative to the stator of the screw 33.

[0062] Accordingly, the through hole 203 of the moving valve plate 22 can rotate around a circle with a revolution radius equal to the eccentricity of the rotor of the screw 33. In a preferred embodiment, when the flow-through area is at its maximum, the through hole 203 of the moving valve plate 22 can coincide with the eccentric hole 201 of the static valve plate 21.

[0063] In the present invention, the moving valve plate 22 is configured to be able to move within the range of the static valve plate 21 under the driving action of the rotor of the screw 33, so as to periodically change the overlapping area between the through hole 203 of the moving valve plate 22 and the eccentric hole 201 of the static valve plate 21, thereby achieving the purpose of changing the flow-through area of the drilling fluid from the static valve plate 21 to the moving valve plate 22.

[0064] It is easy to understand that in the above process, the present invention will generate pressure pulses and can act on the drill string assembly to generate periodic gentle vibrations, so as to achieve the effect of reducing the friction resistance of the drill string.

[0065] In one embodiment, as Figure 7 shown, a bypass hole 202 concentrically arranged with the eccentric hole 201 and configured as a partial arc structure is provided on the static valve plate 21. In the present invention, the bypass hole 202 is configured to be generally crescent-shaped, which is to reduce the pressure difference when the maximum flow-through area is formed between the static valve plate 21 and the moving valve plate 22, so as to ensure that the hydraulic impact oscillation drill 100 can operate smoothly in the well.

[0066] Preferably, when the maximum flow-through area is formed between the static valve plate 21 and the moving valve plate 22, the through hole 203 of the moving valve plate 22 coincides with the eccentric hole 201 of the static valve plate 21. At this time, the bypass hole 202 is completely communicated with the low-pressure area (not shown) of the moving valve plate 22 to adjust the pressure difference between the static valve plate 21 and the moving valve plate 22.

[0067] According to the present invention, as Figure 4As shown, the static valve plate 21 includes a static valve plate seat 211 and a static valve plate sleeve 212. The static valve plate seat 211 and the static valve plate sleeve 212 are assembled by interference fit, and the static valve plate sleeve 212 is made of cemented carbide. In this way, the static valve plate 21 can have good erosion resistance, thus significantly improving the service life of the static valve plate 21.

[0068] In one embodiment, as Figure 2 and 6 shown, the hydraulic impact oscillation drill tool further includes a splash guard 41 that is hermetically connected to the inner peripheral surface of the housing 10 through a spline, so as to ensure that the splash guard 41 and the housing 10 can rotate synchronously.

[0069] Preferably, the inner hole wall surface of the splash guard 41 can be subjected to surface treatments such as spraying cemented carbide, chrome plating, nitriding, etc. to improve its erosion resistance.

[0070] In addition, the static valve plate 21 is connected to the splash guard 41 through a jaw coupling structure, so that the static valve plate 21 cannot rotate relative to the splash guard 41 and the splash guard 41 cannot rotate relative to the housing 10.

[0071] Preferably, as Figure 2 shown, the hydraulic impact oscillation drill tool further includes a gear sleeve 42 disposed on the upper end surface of the splash guard 41 and used for embedding into the static valve plate seat 211. Thus, the static valve plate 21 cannot rotate relative to the splash guard 41, that is, the static valve plate 21 can only move synchronously with the splash guard 41.

[0072] In one embodiment, as Figure 2 shown, a plurality of limiting blocks 213 that extend radially outward and abut against the housing 10 are arranged at intervals along the circumferential direction of the static valve plate seat 211. It is easy to understand that the teeth of the limiting blocks 213 and the gear sleeve 42 are alternately distributed along the circumferential direction, so as to realize the limiting effect on the static valve plate 21 through the combination of the gear sleeve 42 and the limiting blocks 213.

[0073] It should be noted that in the initial state, there is a margin between the impact main shaft 62 in the energy conversion mechanism 60 and the static valve plate 21. In addition, during the working process, the static valve plate 21 and the splash guard 41 can only move slightly axially, and their axial movement positions are limited by the lower end surface of the impact main shaft 62 in the energy conversion mechanism 60.

[0074] According to the present invention, as Figure 5 shown, the dynamic valve plate 22 includes a dynamic valve plate seat 221, and a plurality of water holes 204 are arranged at intervals along the circumferential direction of the dynamic valve plate seat 221. Among them, the drilling fluid sequentially flows downstream through the energy conversion mechanism 60, the eccentric hole 201 of the static valve plate 21, the through hole 203 of the dynamic valve plate 22, and the water holes 204 of the dynamic valve plate seat 221.

[0075] In a preferred embodiment of the present invention, the nozzle 204 is axially within the range of the splash guard 41. Thus, the drilling fluid flowing out through the nozzle 204 will impact on the splash guard 41, thereby preventing the erosion of the inner wall of the housing 10 by the drilling fluid and playing a role in protecting the housing 10.

[0076] In the present invention, the splash guard 41 can be disassembled and replaced, thereby effectively extending the service life of the hydraulic impact oscillator 100.

[0077] According to the present invention, as Figure 5 shown, the dynamic valve plate 22 further includes a dynamic valve plate sleeve 222. The dynamic valve plate seat 221 and the dynamic valve plate sleeve 222 are assembled by interference fit, and the dynamic valve plate sleeve 222 is made of cemented carbide. In this way, the dynamic valve plate 22 can have good erosion resistance, thus significantly improving the service life of the dynamic valve plate 22.

[0078] In one embodiment, the diameter of the dynamic valve plate sleeve 222 is smaller than the diameter of the static valve plate sleeve 212, and the dynamic valve plate sleeve 222 is circumferentially within the range of the static valve plate sleeve 212. Thus, the dynamic valve plate sleeve 222 can rotate periodically on the static valve plate sleeve 212 under the driving action of the rotor of the screw 33, the anti-drop rod 31 and the dynamic valve plate 22, and rely on the change of the overlapping area between the through hole 203 of the dynamic valve plate 22 and the eccentric hole 201 of the static valve plate 21, so that the flow area of the drilling fluid from the static valve plate 21 to the dynamic valve plate 22 changes periodically to generate high-frequency pressure pulses, and this pressure pulse can cause the vibration of the lower drill string assembly (not shown) to prevent sticking, and at the same time act on the energy conversion mechanism to achieve hydraulic axial impact pressurization.

[0079] In a preferred embodiment, the inner diameter of the side through hole 202 is not less than the outer diameter of the dynamic valve plate sleeve 222. Therefore, when the flow area is at its maximum (i.e., the through hole 203 of the dynamic valve plate 22 is completely coincident with the eccentric hole 201 of the static valve plate 21), the side through hole 202 will be completely exposed, so that it can be completely communicated with the low-pressure area of the dynamic valve plate 22.

[0080] In one embodiment, as Figure 2 shown, the fastener includes a first fixing member 321 configured in an octagonal structure. And, an axially upwardly extending through slot 223 is formed at the joint of the dynamic valve plate seat 221 and the fastener. It is easy to understand that the through slot 223 is adapted to the first fixing member 321 and can limit the relative rotation of the first fixing member 321, thereby ensuring that the anti-drop rod 31 and the dynamic valve plate 22 can move synchronously, which is beneficial to the transfer of the drilling pressure during sliding directional drilling and further improves the directional efficiency and drilling speed.

[0081] In one embodiment, as Figure 2As shown, the fastener further includes a second fixing member 322 disposed between the first fixing member 321 and the anti-falling rod 31. Preferably, the second fixing member 322 is configured in an octagonal structure, and the volume of the second fixing member 322 is larger than that of the first fixing member 321.

[0082] In one embodiment, as Figure 2 shown, the driving mechanism 30 further includes an octagonal pad 50 sleeved outside the anti-falling rod 31. Preferably, the octagonal pad 50 is adapted to the second fixing member 322, so as to be able to limit the relative rotation of the second fixing member 322 to ensure that the rotor of the screw 33, the anti-falling rod 31 and the moving valve disc 22 can perform synchronous movement.

[0083] In one embodiment, as Figure 3 shown, the energy conversion mechanism 60 includes a cylinder block 61, an impact main shaft 62 concentrically arranged inside the cylinder block 61, a piston 63 disposed in the annular space between the cylinder block 61 and the impact main shaft 62, and a joint 64 disposed between the cylinder block 61 and the impact main shaft 62. Among them, the piston 63 is fixedly connected to the joint 64 and the impact main shaft 62 by threads. The joint 64 in the present invention is configured as an octagonal joint or a hexagonal joint.

[0084] In one embodiment, as Figure 3 shown, sealing rings 65 are provided between the piston 63 and the cylinder block 61 and the impact main shaft 62 respectively.

[0085] It is easy to understand that the present invention realizes the axial hydraulic pressurization of the screw 33 and the drill bit by using the pressure difference between the inner part of the cavity of the piston 63 and the outer annular space of the housing 10. Since the present invention can rely on the change of the overlapping area between the through hole 203 of the moving valve disc 22 and the eccentric hole 201 of the static valve disc 21 during operation, the flow area of the drilling fluid from the static valve disc 21 to the moving valve disc 22 is periodically changed to generate high-frequency pressure pulses, and the internal and external pressure differences acting on the piston 63 will also pulsate, so as to realize the axial hydraulic impact on the screw 33 and the drill bit to improve the rock-breaking efficiency of the drill bit.

[0086] In one embodiment, as Figure 3 shown, the energy conversion mechanism 60 further includes an anti-falling member 66 disposed radially outside the impact main shaft 62 and used to limit the movement stroke of the piston 63. Preferably, two anti-falling members 66 are provided and are respectively embedded on both sides of the impact main shaft 62.

[0087] In one embodiment, the present invention is mainly applied to the construction of extended-reach wells and horizontal wells in oil drilling, and can also be used for downhole directional drilling construction in fields such as geological exploration, water wells, and geothermal energy.

[0088] Compared with the prior art, the advantages of the present invention are:

[0089] First, the present invention utilizes the surplus energy of the screw 33 driving the drill bit to drive the pulse generating mechanism 20 to generate pressure pulses, causing the drill string to generate periodic gentle vibrations, thereby reducing the friction of the bottom hole assembly near the bit, improving the transfer of the weight on bit, increasing the rate of penetration, and enhancing the extension ability of extended reach wells and horizontal wells. Further, the problem of difficult tool face control is solved.

[0090] Specifically, the moving valve disc sleeve 222 in the present invention can rotate periodically within the range of the static valve disc sleeve 212 under the driving action of the rotor of the screw 33, the anti-falling rod 31, and the moving valve disc 22. Depending on the change in the overlapping area between the through hole 203 of the moving valve disc 22 and the eccentric hole 201 of the static valve disc 21, the flow area of the drilling fluid from the static valve disc 21 to the moving valve disc 22 is changed periodically to generate high-frequency pressure pulses, and the pressure pulses can cause the vibration of the lower drill string assembly (not shown) to prevent sticking.

[0091] Second, the present invention can also generate hydraulic impact on the bottom hole bit, which is beneficial to the transfer of the weight on bit during sliding directional drilling, so as to achieve the purpose of increasing the rock-breaking energy and improving the directional efficiency and drilling speed.

[0092] Specifically, when the hydraulic impact oscillator drill string 100 is working, due to the pressure pulse generated by the pulse generating mechanism 20, the internal and external pressure difference acting on the piston 63 will also pulsate, thereby realizing axial hydraulic impact and improving the rock-breaking efficiency of the bit.

[0093] The above is only the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art can easily make changes or variations within the disclosure scope of the present invention, and such changes or variations should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A hydraulic impact oscillator drill tool, comprising: a housing (10), a pulse generating mechanism (20), which includes a static valve disc (21) abutting against the inner wall surface of the housing (10), and a dynamic valve disc (22) abutting against the lower end surface of the static valve disc (21), a driving mechanism (30) arranged downstream of the pulse generating mechanism, which includes a drop prevention rod (31), a fastener arranged between the drop prevention rod (31) and the dynamic valve disc (22), and a screw rod (33) arranged downstream of the drop prevention rod (31), wherein a stator and a rotor are provided on the screw rod (33), and the free end of the drop prevention rod (31) is fixedly connected to the rotor, wherein the rotor, the drop prevention rod (31) and the dynamic valve disc (22) are coaxially arranged, the rotor is configured to be able to perform a planetary motion relative to the stator, so that the dynamic valve disc (22) moves on the static valve disc (21) to change the flow area of the drilling fluid from the static valve disc (21) to the dynamic valve disc (22).

2. The hydraulic impact oscillation drilling tool according to claim 1, wherein An eccentric hole (201) allowing the drilling fluid to pass through is provided on the static valve disc (21), and the eccentricity of the eccentric hole (201) is the same as the eccentricity of the rotor relative to the stator.

3. The hydraulic impact oscillator drill tool according to claim 2, wherein A through hole (203) having the same aperture as the eccentric hole (201) is provided on the dynamic valve disc (22), the dynamic valve disc (22) is configured to be able to periodically change the overlapping area between the through hole (203) and the eccentric hole (201) under the action of the rotor.

4. The hydraulic impact oscillation drill tool according to claim 3, characterized in that, The static valve disc (21) includes a static valve disc seat (211), and a static valve disc sleeve (212) forming an interference fit with the static valve disc seat (211), The hydraulic impact oscillator drill tool further includes a splash-proof sleeve (41) hermetically connected to the inner peripheral surface of the housing (10) through a spline, and a tooth sleeve (42) provided on the upper end surface of the splash-proof sleeve (41) and configured to be embedded into the static valve disc seat (211).

5. The hydraulic impact oscillation drill tool according to claim 4, wherein The dynamic valve disc (22) includes a dynamic valve disc seat (221), and a plurality of water holes (204) are arranged at intervals along the circumference of the dynamic valve disc seat (221), wherein the water holes (204) are axially within the range of the splash-proof sleeve (41).

6. The hydraulic impact oscillator according to claim 5, wherein, The dynamic valve disc (22) further includes a dynamic valve disc sleeve (222) forming an interference fit with the dynamic valve disc seat (221), the diameter of the dynamic valve disc sleeve (222) is smaller than the diameter of the static valve disc sleeve (212), and the dynamic valve disc sleeve (222) is circumferentially within the range of the static valve disc sleeve (212).

7. The hydraulic impact oscillating drilling tool according to claim 6, characterized in that, A bypass hole (202) concentric with the eccentric hole (201) and configured to be a partial arc structure is provided on the static valve disc (21), and the inner diameter of the bypass hole (202) is not less than the outer diameter of the dynamic valve disc sleeve (222).

8. The hydraulic impact oscillating drill tool according to claim 7, characterized in that, The fastener includes a first fixing member (321) configured in an octagonal structure. A through groove (223) extending axially upward and adapted to the first fixing member (321) is formed at the joint between the moving valve disc seat (221) and the fastener to allow the anti-falling rod (31) to move synchronously with the moving valve disc (22).

9. The hydraulic impact oscillating drill tool according to claim 8, characterized in that, The fastener further includes a second fixing member (322) configured in an octagonal structure and disposed between the first fixing member (321) and the anti-falling rod (31). The volume of the second fixing member (322) is larger than that of the first fixing member (321).

10. The hydraulic impact oscillating drill tool according to claim 9, characterized in that, The driving mechanism further includes an octagonal pad (50) sleeved outside the anti-falling rod (31) and adapted to the second fixing member (322).

11. The hydraulic impact oscillator drill tool according to claim 10, wherein, The hydraulic impact oscillator further includes an energy conversion mechanism (60) disposed upstream of the pulse generating mechanism. The energy conversion mechanism includes a cylinder block (61), an impact main shaft (62) concentrically arranged in the cylinder block (61), a piston (63) disposed in the annular space between the cylinder block (61) and the impact main shaft (62), and a joint (64) disposed between the cylinder block (61) and the impact main shaft (62). Wherein, sealing rings (65) are provided between the piston (63) and both the cylinder block (61) and the impact main shaft (62).

12. The hydraulic impact oscillation drill tool according to claim 11, characterized in that, The energy conversion mechanism further includes an anti-falling member (66) radially disposed outside the impact main shaft (62) and used to limit the movement stroke of the piston (63).

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