Pressure pulse assembly and pressure pulse and axial impact combined resistance reduction tool

Abstract

Drilling fluid passes through a rotational flow injection groove of a lower core shaft to form a jet flow beam, an impeller is pushed to rotate, a rotating speed difference is formed between a guide shaft and a telescopic shaft under the driving of the impeller, so that the overflowing area of a throttling hole is changed, and pressure pulse waves are generated; and the piston is pushed to do reciprocating vibration together with the transmission shaft and the washing pipe to generate axial hydraulic oscillating force. The invention further discloses a pressure pulse and axial impact combined resistance reduction tool, axial mechanical impact force and hydraulic oscillating force can be generated at the same time, and the friction reduction and resistance reduction effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical fields of oil and gas exploration, geological exploration, and geothermal well development, and particularly relates to a pressure pulse assembly and a combined drag reduction tool for pressure pulse and axial impact. Background Art

[0002] With the continuous expansion of the exploration and development process of unconventional oil and gas resources such as shale gas and shale oil, highly deviated directional wells and horizontal wells with long horizontal sections have become the main production means. However, due to their characteristics of small wellbore size, large horizontal displacement, and complex wellbore trajectory, the contact area between the drill string system and the wellbore wall increases, resulting in technical problems such as large friction and torque during drilling, difficulty in applying bottom hole pressure, and instability of the tool face of directional instruments, which severely restricts the improvement of drilling speed and efficiency.

[0003] To solve this technical problem, researchers have carried out the research and application of drag reduction tools. Existing drag reduction tools represented by hydraulic oscillators have relatively single functions, can only generate axial hydraulic oscillation forces, and have stator rubber elements inside, with insufficient high-temperature and oil-base resistance performance, and their use effects are affected to a certain extent in deep high-temperature, large-displacement, and long horizontal section drilling operations.

[0004] Therefore, it is necessary to develop a new type of high-temperature resistant drag reduction tool that can achieve hydraulic oscillation function to solve the technical problems of deep high-temperature, large-displacement, and long horizontal section drilling. Summary of the Invention

[0005] In view of this, the present invention provides a pressure pulse assembly and a combined drag reduction tool for pressure pulse and axial impact, which can generate axial hydraulic oscillation forces, improve the energy utilization rate of drilling fluid, and is beneficial to enhancing the drag reduction effect.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A pressure pulse assembly for cooperating with an upstream component, comprising: a lower housing and an impeller mechanism, a lower mandrel, a telescopic shaft, and a lower sub provided therein;

[0008] The upper end of the lower mandrel is fixedly connected to the upper end of the lower housing, and the lower end of the lower mandrel is inserted into the impeller mechanism; the top of the inner hole of the lower mandrel communicates with the through hole of the upstream component to jointly form a central middle flow channel; a swirl injection groove deflected along a first rotation direction is provided on the side wall of the lower mandrel; an inner side of the upper part of the impeller mechanism is provided with blades deflected along a second rotation direction, and the second rotation direction is opposite to the first rotation direction;

[0009] The lower end of the impeller mechanism is inserted into the upper end of the telescopic shaft, and the central holes of the lower part of the impeller mechanism and the telescopic shaft jointly form a central lower flow channel;

[0010] The lower end of the telescopic shaft is inserted into the lower joint and is rotationally drivingly engaged with the lower joint through a mating surface, and a throttling hole is provided in the mating surface;

[0011] An inner cavity of the lower joint is provided in the upper part of the lower joint, and the lower joint is fixedly connected to the lower end of the lower housing;

[0012] When the telescopic shaft descends to the lowest position, the flow-through area of the throttling hole and the inner cavity of the lower joint is the largest; when the telescopic shaft ascends to the highest position, the flow-through area of the throttling hole and the inner cavity of the lower joint is the smallest.

[0013] Preferably, the number of the swirl injection grooves is multiple and is evenly arranged along the circumferential direction of the lower mandrel;

[0014] The number of the blades is greater than the number of the swirl injection grooves, and the blades are evenly arranged along the circumferential direction of the impeller mechanism;

[0015] An impeller inner cavity is provided between adjacent blades, and the impeller inner cavity communicates with the lower central flow channel.

[0016] Preferably, the impeller mechanism includes: an impeller body and a guide shaft;

[0017] The lower end of the impeller body is fixedly connected to the upper end of the guide shaft, the lower end of the guide shaft is inserted into the telescopic shaft, and the central hole of the guide shaft and the central hole of the telescopic shaft together form a lower central flow channel;

[0018] A guiding structure is provided between the outer wall of the guide shaft and the inner wall of the telescopic shaft.

[0019] Preferably, the guiding structure includes:

[0020] A guide rail provided on the outer wall surface of the guide shaft, the guide rail extends along the axial direction of the guide shaft and undulates in the circumferential direction to form a wave shape;

[0021] A pin fixed to the inner wall of the telescopic shaft, the end of the pin is inserted into the guide rail, and the pin can move along the guide rail.

[0022] Preferably, it further includes: a ball bearing provided in the lower housing;

[0023] The upper end surface of the impeller contacts the ball bearing.

[0024] Preferably, the mating surface is polygonal, and the throttling holes are evenly arranged.

[0025] A pressure pulse and axial impact combined drag reduction tool includes: an upstream component and the pressure pulse assembly as described above;

[0026] The upstream component is an axial impact assembly.

[0027] Preferably, the axial impact assembly includes: a middle housing and an upper mandrel, an impact hammer and a flow distribution cover disposed therein;

[0028] The upper end of the middle housing is fixedly connected to the upper mandrel, and the lower end of the middle housing is fixedly connected to the lower housing;

[0029] Middle communication holes and lower communication holes are respectively arranged on the upper and lower sides of the wall surface of the middle housing. An upper impact hammer cavity that can communicate with the middle communication hole is arranged between the upper end inside the middle housing, the upper mandrel, and the upper end surface of the impact hammer. A lower impact hammer cavity that can communicate with the lower communication hole is arranged between the lower end inside the middle housing, the upper mandrel, the lower end surface of the impact hammer, and the upper end surface of the lower housing;

[0030] An upper annular cavity is arranged between the inner side of the upper end of the impact hammer and the upper mandrel. A lower annular cavity that can accommodate the up and down movement of the flow distribution cover is arranged on the inner side of the lower end of the impact hammer. The area of the upper annular cavity is smaller than the area of the lower annular cavity;

[0031] An upper diversion hole that can communicate with the upper annular cavity is arranged on the upper side of the wall surface of the upper mandrel, and a lower diversion hole that can communicate with the lower annular cavity is arranged on the lower side of the wall surface of the upper mandrel;

[0032] The lower end of the upper mandrel is inserted into the lower housing.

[0033] Preferably, the inner diameter of the middle part of the impact hammer is d2, the inner diameter of the upper end of the impact hammer is d1, and the outer diameter of the lower annular cavity is d3; in terms of numerical magnitude, d3 > d1 > d2;

[0034] The outer diameter of the upper end of the upper mandrel is d1, and the outer diameters of the middle and lower parts of the upper mandrel are d2.

[0035] As can be seen from the above technical solutions, when the pressure pulse assembly provided by the present invention is working, the drilling fluid flows along the central flow channel in the middle and sprays out through the swirl injection grooves, forming a jet beam that deflects clockwise. Then, it flows downward through the inner cavity of the impeller to the lower central flow channel. The jet beam acts on the side wall surface of the blade to form a rotational impact force, thereby driving the impeller and the guide shaft to generate a clockwise rotational movement. Among them, since the number of swirl injection grooves is different from the number of blades, at least one swirl injection groove is always kept unobstructed during the rotation of the blade, thus ensuring the continuity and stability of the impeller rotation. The telescopic shaft is rotationally constrained by the hexagonal mating surface, so a rotational speed difference is formed between the guide shaft and the telescopic shaft, prompting the pin to move along the guide rail. When the pin is located at the peak point of the guide rail, the telescopic shaft is at the highest position. At this time, the throttle hole is blocked by the hexagonal mating surface, and the flow area is in the minimum state. When the pin is located at the valley point of the guide rail, the telescopic shaft is at the lowest position. At this time, the throttle hole completely extends out of the hexagonal mating surface, and the flow area is in the maximum state. This cycle makes the drilling fluid in the lower central flow channel generate a pressure pulse wave, which is transmitted upward to the lower cavity of the piston. When the amplitude of the pressure pulse wave in the lower cavity of the piston is the largest, it pushes the piston, the wash pipe, and the transmission shaft to overcome the annular pressure in the upper cavity of the piston and the acting force of the disc spring and move axially outward. When the amplitude of the pressure pulse wave in the lower cavity of the piston is the smallest, the piston, the wash pipe, and the transmission shaft move axially inward under the annular pressure in the upper cavity of the piston and the acting force of the disc spring. Therefore, the periodic change of the pressure pulse wave will also push the transmission shaft to vibrate reciprocally and generate an axial hydraulic oscillation force, which will also be transmitted upward to the upper drill string through the transmission shaft.

[0036] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention has an axial hydraulic oscillation function, which is more conducive to converting the static friction state between the downhole drill string system and the well wall into a dynamic friction state, achieving the effect of reducing friction and resistance.

[0038] 2. The internal working parts of the present invention are independent of each other and do not interfere with each other, enabling the hydraulic oscillation function to be fully exerted and improving the energy utilization rate of the drilling fluid.

[0039] 3. There is no rubber material inside the present invention. In particular, the pressure pulse assembly uses a fully metal impeller as the rotational power source. Compared with the conventional hydraulic oscillator that uses a rubber - material screw motor as the rotational power source, it has better high - temperature and oil - based resistance performance and a longer service life. Description of the Drawings

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0041] Figure 1 Schematic diagram of the axial hydraulic oscillation drag reduction tool provided by the first embodiment of the present invention;

[0042] Figure 2 Schematic diagram of the structure of the pressure pulse and axial impact combined drag reduction tool provided by the second embodiment of the present invention;

[0043] Figure 3 For Figure 1 And Figure 2 Schematic diagram of the A-A cross-section in

[0044] Figure 4 For Figure 2 Schematic diagram of the B-B cross-section in

[0045] Figure 5 For Figure 1 And Figure 2 Schematic diagram of the C-C cross-section in

[0046] Figure 6 For Figure 1 And Figure 2 Schematic diagram of the D-D cross-section in

[0047] Figure 7 For Figure 1 And Figure 2 Schematic diagram of the E-E cross-section in

[0048] Figure 8 Schematic diagram of the throttle hole of the pressure pulse and axial impact combined drag reduction tool provided by the present invention in the state of the minimum flow area;

[0049] Figure 9 Schematic diagram of the throttle hole of the pressure pulse and axial impact combined drag reduction tool provided by the present invention in the state of the maximum flow area

[0050] Figure 10 Schematic diagram of the unfolded outer wall surface of the guide shaft of the pressure pulse and axial impact combined drag reduction tool provided by the present invention;

[0051] Figure 11 Schematic diagram of the first-stage working state of the impact hammer of the pressure pulse and axial impact combined drag reduction tool provided by the present invention;

[0052] Figure 12 Schematic diagram of the second-stage working state of the impact hammer of a drag reduction tool combining pressure pulse and axial impact provided by the present invention;

[0053] Figure 13 Schematic diagram of the third-stage working state of the impact hammer of a drag reduction tool combining pressure pulse and axial impact provided by the present invention;

[0054] Figure 14 Schematic diagram of the fourth-stage working state of the impact hammer of a drag reduction tool combining pressure pulse and axial impact provided by the present invention. Specific embodiments

[0055] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0056] The first embodiment provided by the present invention is as Figure 1 shown, which is an axial hydraulic oscillation drag reduction tool, including a hydraulic oscillation assembly and a pressure pulse assembly, that is, the upstream component is the hydraulic oscillation assembly;

[0057] The drilling fluid forms a jet beam through the swirl injection groove of the lower mandrel, pushes the impeller to rotate, and a rotational speed difference is formed between the guide shaft and the telescopic shaft driven by the impeller, so that the flow area of the throttle hole changes to generate a pressure pulse wave, and pushes the piston, the transmission shaft, and the wash pipe to reciprocate to generate an axial hydraulic oscillation force. This solution can generate an axial hydraulic oscillation force and improve the drag reduction effect.

[0058] Specifically, the hydraulic oscillation assembly is used between the upper drill string and the axial impact assembly, and includes: a transmission shaft 1, an elastic member, an oscillation housing, a wash pipe 5, and a piston 6; the oscillation housing has an upper part of the oscillation housing and a lower part of the oscillation housing;

[0059] The upper end of the transmission shaft 1 is used to connect to the upper drill string, and the lower end of the transmission shaft 1 sequentially passes through the upper part of the oscillation housing and the elastic member and is fixedly connected to the upper end of the wash pipe 5; the transmission shaft 1 is in transmission cooperation with the upper part of the oscillation housing and can move up and down in the upper part of the oscillation housing, and the central holes of the transmission shaft 1 and the wash pipe 5 are communicated to form an upper central flow channel 19;

[0060] The upper end face of the wash pipe 5 is in contact with the elastic member, and the lower end of the wash pipe 5 is fixedly connected to the piston 6;

[0061] The piston 6 can move up and down along the inner wall of the lower part of the oscillating housing. A piston upper chamber 20 is provided between the upper end face of the piston 6 and the inner wall of the lower part of the oscillating housing. The piston upper chamber 20 communicates with a communication hole 21 opened on the lower wall surface of the oscillating housing; a piston lower chamber 22 is provided between the lower end face of the piston 6 and the inner wall of the lower part of the oscillating housing, and the piston lower chamber 22 is used to communicate with the central flow channel 27 in the middle of the axial impact assembly.

[0062] Preferably, the outer side of the transmission shaft 1 is in transmission cooperation with the upper part of the oscillating housing through a spline transmission surface 38; as Figure 1 shown, the upper part of the oscillating housing is a spline sleeve 2. Further, the upper part and the lower part of the oscillating housing are detachably connected; as Figure 1 shown, the lower part of the oscillating housing is an upper housing 4.

[0063] The upper end face of the elastic member fits with the lower end face of the upper part of the oscillating housing. The elastic member can specifically be a disc spring 3.

[0064] As Figure 1 shown, when an axial hydraulic oscillation drag reduction tool provided by the first embodiment of the present invention is working, drilling fluid flows into the piston lower chamber 22 and the central flow channel 27 in the middle from the upper central flow channel 19, and then sprays out through the swirl injection grooves 32 to form a jet beam deflecting clockwise (as Figure 5 shown), and then flows downward to the lower central flow channel 34 through the inner cavity 33 of the impeller. The jet beam acts on the side wall surface of the blade 39 to form a rotary impact force, thereby driving the impeller 13 and the guide shaft 15 to generate a clockwise rotational movement. Among them, since the number of swirl injection grooves 32 is different from the number of blades 39, at least one swirl injection groove 32 is always kept unblocked during the rotation of the blade 39, thereby ensuring the continuity and stability of the rotation of the impeller 13. And the telescopic shaft 17 is rotationally restricted by the hexagonal mating surface 40, so a rotational speed difference is formed between the guide shaft 15 and the telescopic shaft 17, prompting the pin 16 to move along the guide rail 37 (as Figure 8 shown). When the pin 16 is at the peak point of the guide rail 37, the telescopic shaft 17 is at the highest position. At this time, the throttle hole 35 is blocked by the hexagonal mating surface 40, and the flow area is in the minimum state (as Figure 9 shown); when the pin 16 is at the trough point of the guide rail 37, the telescopic shaft 17 is at the lowest position. At this time, the throttle hole 35 completely extends out of the hexagonal mating surface 40, and the flow area is in the maximum state (as Figure 10As shown, this cycle is repeated, causing a pressure pulse wave to be generated in the drilling fluid within the lower central flow channel 34. This pressure pulse wave is transmitted upward to the lower chamber 22 of the piston. When the amplitude of the pressure pulse wave in the lower chamber 22 of the piston is at its maximum, it pushes the piston 7, the swab 5, and the drive shaft 1 together to move axially outward against the annular pressure in the upper chamber 20 of the piston and the force of the disc spring 3. When the amplitude of the pressure pulse wave in the lower chamber 22 of the piston is at its minimum, the piston 7, the swab 5, and the drive shaft 1 move axially inward under the action of the annular pressure in the upper chamber 20 of the piston and the force of the disc spring 3. Therefore, the periodic change of the pressure pulse wave will also drive the drive shaft 1 to vibrate reciprocally and generate an axial hydraulic oscillation force, which will also be transmitted upward through the drive shaft 1 to the upper drill string.

[0065] It can be seen that an axial hydraulic oscillation drag reduction tool can generate a hydraulic oscillation force, and each driving component is independent and does not interfere with each other, ensuring stable output function, improving the energy utilization rate of the drilling fluid, and helping to enhance the drag reduction effect.

[0066] The second embodiment provided by the present invention is as Figure 2 shown, which is a combined drag reduction tool for pressure pulse and axial impact, including a hydraulic oscillation assembly, a mechanical impact assembly, and a pressure pulse assembly; the hydraulic oscillation assembly and the pressure pulse assembly therein can refer to the aforementioned first embodiment.

[0067] During operation, a part of the drilling fluid enters the upper annular chamber and the lower annular chamber through the upper diversion hole and the lower diversion hole of the upper mandrel, driving the impact hammer and the flow distribution cover to reciprocally impact and generate an axial mechanical impact force. Another part of the drilling fluid forms a jet beam through the swirl injection groove of the lower mandrel, pushing the impeller to rotate. A rotational speed difference is formed between the guide shaft and the telescopic shaft driven by the impeller, causing the flow area of the throttle hole to change and generating a pressure pulse wave, which pushes the piston, the drive shaft, and the swab to vibrate reciprocally to generate an axial hydraulic oscillation force. This solution can generate both axial mechanical impact force and hydraulic oscillation force, enhancing the drag reduction effect.

[0068] Specifically, the hydraulic oscillation assembly includes: drive shaft 1, disc spring 3, swab 5, piston 6;

[0069] The mechanical impact assembly includes: upper mandrel 7, impact hammer 9, flow distribution cover 10;

[0070] The pressure pulse assembly includes: ball bearing 12, impeller 13, lower mandrel 14, guide shaft 15, pin 16, telescopic shaft 17;

[0071] The housing assembly includes: spline sleeve 2, upper housing 4, middle housing 8, lower housing 11, lower sub 18.

[0072] Inside the upper housing 4, a hydraulic oscillation assembly is placed. The upper and lower ends of the upper housing 4 are respectively threadedly connected to the spline sleeve 2 and the middle housing 8. An upper communication hole 21 is provided on the wall surface of the upper housing 4;

[0073] The lower end of the transmission shaft 1 passes through the spline sleeve 2 and the disc spring 3 and is threadedly connected to the washpipe 5. The outer side of the transmission shaft 1 is in transmission cooperation with the spline sleeve 2 through a spline transmission surface 38 and can move up and down within the spline sleeve 2. The central holes of the transmission shaft 1 and the washpipe 5 together form an upper central flow channel 19;

[0074] The upper surface of the washpipe 5 is in contact with the disc spring 3, and the lower end of the washpipe 5 is threadedly connected to the piston 6;

[0075] The piston 6 can move up and down along the inner wall of the upper housing 4. A piston upper chamber 20 is provided between the upper end face of the piston 6 and the inner wall of the upper housing 4. A piston lower chamber 22 is provided between the lower end face of the piston 6 and the inner wall of the upper housing 4. The piston upper chamber 20 is communicated with the upper communication hole 21;

[0076] Inside the middle housing 8, a mechanical impact assembly is placed. On the upper and lower sides of the wall surface of the middle housing 8, a middle communication hole 24 and a lower communication hole 30 are respectively provided. The upper end inside of the middle housing 8 is threadedly connected to the upper mandrel 7. The lower end of the middle housing 8 is threadedly connected to the lower housing 11. An impact hammer upper chamber 23 that can be communicated with the middle communication hole 24 is provided between the upper end inside of the middle housing 8, the upper mandrel 7, and the upper end face of the impact hammer 9. An impact hammer lower chamber 31 that can be communicated with the lower communication hole 30 is provided between the lower end inside of the middle housing 8, the upper mandrel 7, the lower end face of the impact hammer 9, and the upper end face of the lower housing 11;

[0077] The minimum inner diameter of the impact hammer 9 is d2. An upper annular chamber 26 is provided between the upper end inside of the impact hammer 9 and the upper mandrel 7. The inner diameter of the upper end of the impact hammer 9 is d1. A lower annular chamber 29 that can accommodate the up and down movement of the flow distribution cover 10 is provided inside the impact hammer 9. And the outer diameter of the lower annular chamber 29 is d3. In terms of numerical values, d3 > d1 > d2;

[0078] Upper guide holes 25 that can be communicated with the upper annular chamber 26 are uniformly provided on the upper side of the wall surface of the upper mandrel 7. Lower guide holes 28 that can be communicated with the lower annular chamber 29 are uniformly provided on the lower side of the wall surface of the upper mandrel 7. The lower end of the upper mandrel 7 is inserted into the lower housing 11;

[0079] Inside the lower housing 11, a pressure pulse assembly is placed. The lower end of the lower housing 11 is threadedly connected to the lower joint 18;

[0080] The upper end of the lower mandrel 14 is threadedly connected to the inner hole of the lower housing 11. The lower end of the lower mandrel 14 is inserted into the impeller 13. The inner hole of the lower mandrel 14 and the through hole of the upper mandrel 7 together form a middle central flow channel 27. A number of counterclockwise-deflecting swirl injection grooves 32 are uniformly provided on the wall surface of the lower mandrel 14;

[0081] The upper end face of the impeller 13 contacts the ball bearing 12. The lower end of the impeller 13 is threadedly connected to the guide shaft 15. A number of blades 39 that deflect clockwise and have a different number from the swirl injection grooves 32 are evenly arranged inside the impeller 13. An impeller inner cavity 33 is arranged between adjacent blades 39;

[0082] The lower end of the guide shaft 15 is inserted into the telescopic shaft 17. Wave-shaped guide rails 37 are evenly arranged on the outer wall surface of the guide shaft 15;

[0083] The pin 16 is threadedly connected to the telescopic shaft 17 and inserted into the guide rail 37 after passing through the telescopic shaft 17, so that the pin 16 can move along the guide rail 37;

[0084] The central holes of the telescopic shaft 17 and the guide shaft 15 together form a lower central flow channel 34. The lower end of the telescopic shaft 17 is inserted into the lower joint 18 and is in mating contact with the lower joint 18 through a hexagonal mating surface 40. Throttle holes 35 are evenly arranged on the hexagonal mating surface 40 of the telescopic shaft 17;

[0085] A lower joint inner cavity 36 is arranged inside the lower joint 18.

[0086] When a pressure pulse and axial impact combined drag reduction tool is working, the drilling fluid flows into the lower cavity 22 of the piston from the upper central flow channel 19, and then enters the middle central flow channel 27 and continues to flow downward. At this time, a part of the drilling fluid respectively passes through the upper diversion hole 25 and the lower diversion hole 28 and enters the upper annular cavity 26 and the lower annular cavity 29 (as Figure 11 shown). Due to the relationship of d3>d1>d2, the acting area in the lower annular cavity 29 is larger than the acting area in the upper annular cavity 26. Under the action of the upward pressure difference, the impact hammer 9 and the flow distribution cover 10 start to move upward. The volumes of the upper annular cavity 26 and the upper cavity 23 of the impact hammer decrease, and the volume of the lower cavity 31 of the impact hammer increases. The drilling fluid in the upper annular cavity 26 flows back to the middle central flow channel 27 through the upper diversion hole 25. The fluid in the upper cavity 23 of the impact hammer is discharged from the middle communication hole 24 to keep the pressure in the cavity stable. The external fluid of the tool flows into the lower cavity 31 of the impact hammer from the lower communication hole 30 to keep the pressure in the cavity stable. The impact hammer 9 moves upward to the highest point and collides with the middle housing 8 to generate an upward axial mechanical impact force. At this time, the flow distribution cover 10 just completely closes the lower diversion hole 28 and continues to move upward (as Figure 12 shown). During the process of the flow distribution cover 10 continuing to move upward and contacting the upper surface of the lower annular cavity 29 (as Figure 13As shown, the lower diversion hole 28 is always in a closed state, and the drilling fluid can only communicate with the upper annular cavity 26 through the upper diversion hole 25. Therefore, under the combined action of the downward pressure of the drilling fluid and the resilience of the middle housing 8, the impact hammer 9 and the flow distribution cover 10 move downward together. The volumes of the upper annular cavity 26 and the upper cavity 23 of the impact hammer increase, and the volume of the lower cavity 31 of the impact hammer decreases. The drilling fluid in the middle central flow channel 27 flows into the upper annular cavity 26 through the upper diversion hole 26. The fluid outside the tool flows into the upper cavity 23 of the impact hammer from the communication hole 26, thereby maintaining the pressure stability in the chamber. The fluid in the lower cavity 31 of the impact hammer is discharged from the lower communication hole 30, thereby maintaining the pressure stability in the chamber. The impact hammer 9 moves downward to the lowest position and collides with the lower housing 11 to generate a downward axial mechanical impact force (as Figure 14 shown). After the flow distribution cover 10 continues to move downward for a certain distance, the lower diversion hole 28 is reopened, and the drilling fluid flows into the lower annular cavity 29 again and pushes the impact hammer 9 and the flow distribution cover 10 to move upward again, starting the reciprocating impact action of the next cycle. The axial mechanical impact force generated by the impact will also be transmitted downward through the housing assembly to the lower drill string.

[0087] At the same time, another part of the drilling fluid continues to flow downward along the middle central flow channel 27 and is ejected through the swirl injection groove 32 to form a jet beam with a clockwise deflection (as Figure 4 shown), and then flows downward through the inner cavity 33 of the impeller to the lower central flow channel 34. The jet beam acts on the side wall surface of the blade 39 to form a rotary impact force, thereby driving the impeller 13 and the guide shaft 15 to generate a clockwise rotational movement. Among them, since the number of swirl injection grooves 32 is different from the number of blades 39, at least one swirl injection groove 32 is always kept unobstructed during the rotation of the blade 39, thereby ensuring the continuity and stability of the rotation of the impeller 13. Since the telescopic shaft 17 is rotationally restricted by the hexagonal mating surface 40, a rotational speed difference is formed between the guide shaft 15 and the telescopic shaft 17, prompting the pin 16 to move along the guide rail 37 (as Figure 7 shown). When the pin 16 is located at the peak point of the guide rail 37, the telescopic shaft 17 is at the highest position. At this time, the throttle hole 35 is blocked by the hexagonal mating surface 40, and the flow area is in the smallest state (as Figure 12 shown); when the pin 16 is located at the valley point of the guide rail 37, the telescopic shaft 17 is at the lowest position. At this time, the throttle hole 35 completely extends out of the hexagonal mating surface 40, and the flow area is in the largest state (as Figure 13As shown, this cycle is repeated, causing a pressure pulse wave to be generated in the drilling fluid within the lower central flow path 34. This pressure pulse wave is transmitted upward to the lower chamber 22 of the piston. When the amplitude of the pressure pulse wave in the lower chamber 22 of the piston is at its maximum, it pushes the piston 7, the swab 5, and the drive shaft 1 together to move axially outward against the annular pressure in the upper chamber 20 of the piston and the force of the disc spring 3. When the amplitude of the pressure pulse wave in the lower chamber 22 of the piston is at its minimum, the piston 7, the swab 5, and the drive shaft 1 move axially inward under the action of the annular pressure in the upper chamber 20 of the piston and the force of the disc spring 3. The periodic change of the pressure pulse wave will also drive the drive shaft 1 to vibrate reciprocally and generate an axial hydraulic oscillating force, which will also be transmitted upward through the drive shaft 1 to the upper drill string.

[0088] It can be seen that a drag reduction tool combining pressure pulse and axial impact can simultaneously generate axial mechanical impact force and hydraulic oscillating force, and the components driven by each are independent of each other and do not interfere with each other, ensuring diversified output functions, improving the energy utilization rate of drilling fluid, and helping to enhance the drag reduction effect.

[0089] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0090] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pressure pulse assembly, characterized in that, For cooperation with the upstream component, including: a lower housing (11) and an impeller mechanism, a lower core shaft (14), a telescopic shaft (17) and a lower joint (18) provided therein; The upper end of the lower core shaft (14) is fixedly connected to the upper end of the lower housing (11), and the lower end of the lower core shaft (14) is inserted into the impeller mechanism; the top of the inner hole of the lower core shaft (14) communicates with the through hole of the upstream component to jointly form a central middle flow channel (27); a swirl injection groove (32) deflecting along a first rotation direction is formed on the side wall of the lower core shaft (14); blades (39) deflecting along a second rotation direction are arranged on the inner side of the upper part of the impeller mechanism, and the second rotation direction is opposite to the first rotation direction; The lower end of the impeller mechanism is inserted into the upper end of the telescopic shaft (17), and the central hole of the lower part of the impeller mechanism and the central hole of the telescopic shaft (17) jointly form a lower central flow channel (34); The lower end of the telescopic shaft (17) is inserted into the lower joint (18) and is rotationally and drivingly matched with the lower joint (18) through a mating surface (40), and a throttle hole (35) is formed in the mating surface (40); An inner cavity (36) of the lower joint is provided in the upper part of the lower joint (18), and the lower joint (18) is fixedly connected to the lower end of the lower housing (11); When the telescopic shaft (17) descends to the lowest position, the flow-through area of the cooperation between the throttle hole (35) and the inner cavity (36) of the lower joint is the largest; when the telescopic shaft (17) ascends to the highest position, the flow-through area of the cooperation between the throttle hole (35) and the inner cavity (36) of the lower joint is the smallest.

2. The pressure pulse assembly according to claim 1, wherein, The number of the swirl injection grooves (32) is multiple and is uniformly arranged along the circumferential direction of the lower core shaft (14); The number of the blades (39) is greater than the number of the swirl injection grooves (32) and is uniformly arranged along the circumferential direction of the impeller mechanism; An impeller inner cavity (33) is arranged between adjacent blades (39), and the impeller inner cavity (33) communicates with the lower central flow channel (34).

3. The pressure pulse assembly according to claim 1, wherein, The impeller mechanism includes: an impeller body (13) and a guide shaft (15); The lower end of the impeller body (13) is fixedly connected to the upper end of the guide shaft (15), the lower end of the guide shaft (15) is inserted into the telescopic shaft (17), and the central hole of the guide shaft (15) and the central hole of the telescopic shaft (17) jointly form a lower central flow channel (34); A guiding structure is arranged between the outer wall of the guide shaft (15) and the inner wall of the telescopic shaft (17).

4. The pressure pulse assembly according to claim 3, wherein The guiding structure includes: A guide rail (37) arranged on the outer wall surface of the guide shaft (15), the guide rail (37) extends along the axial direction of the guide shaft (15) and undulates in the circumferential direction to form a wave shape; A pin (16) fixed to the inner wall of the telescopic shaft (17), the end of the pin (16) is inserted into the guide rail (37), and the pin (16) can move along the guide rail (37).

5. The pressure pulse assembly according to claim 1, characterized in that, It further includes: A ball bearing (12) arranged in the lower housing (11); The upper end surface of the impeller (13) contacts the ball bearing (12).

6. The pressure pulse assembly according to claim 1, wherein, The mating surface (40) is polygonal, and the throttling holes (35) are evenly arranged.

7. A pressure pulse and axial impact combined drag reduction tool, characterized in that Comprising: An upstream component and a pressure pulse assembly as described in any one of claims 1-6; The upstream component is an axial impact assembly.

8. The pressure pulse and axial impact combined drag reduction tool according to claim 7, wherein The axial impact assembly includes: a middle housing (8) and an upper mandrel (7), an impact hammer (9) and a flow distribution cover (10) arranged therein; The upper end of the middle housing (8) is fixedly connected to the upper mandrel (7), and the lower end of the middle housing (8) is fixedly connected to the lower housing (11); On the upper and lower sides of the wall surface of the middle housing (8), a middle communication hole (24) and a lower communication hole (30) are respectively arranged. An impact hammer upper cavity (23) capable of communicating with the middle communication hole (24) is arranged between the upper end of the inner side of the middle housing (8), the upper mandrel (7), and the upper end surface of the impact hammer (9). An impact hammer lower cavity (31) capable of communicating with the lower communication hole (30) is arranged between the lower end of the inner side of the middle housing (8), the upper mandrel (7), the lower end surface of the impact hammer (9), and the upper end surface of the lower housing (11); An upper annular cavity (26) is arranged between the upper end inner side of the impact hammer (9) and the upper mandrel (7), and a lower annular cavity (29) capable of accommodating the up-and-down movement of the flow distribution cover (10) is arranged on the lower end inner side of the impact hammer (9). The area of the upper annular cavity (26) is smaller than the area of the lower annular cavity (29); An upper diversion hole (25) capable of communicating with the upper annular cavity (26) is arranged on the upper side of the wall surface of the upper mandrel (7), and a lower diversion hole (28) capable of communicating with the lower annular cavity (29) is arranged on the lower side of the wall surface of the upper mandrel (7); The lower end of the upper mandrel (7) is inserted into the lower housing (11).

9. The drag reduction tool combining pressure pulse and axial impact according to claim 8, characterized in that, The inner diameter of the middle part of the impact hammer (9) is d2, the inner diameter of the upper end of the impact hammer (9) is d1, and the outer diameter of the lower annular cavity (29) is d3; in terms of numerical magnitude, d3 > d1 > d2; The outer diameter of the upper end of the upper mandrel (7) is d1, and the outer diameters of the middle and lower parts of the upper mandrel (7) are d2.

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