Pressure generating device for well drilling

Abstract

According to the pressure generating device for well drilling, in the device, a plurality of upper rotational flow blades are located below an overflowing channel and arranged around a main shaft, and a plurality of lower rotational flow blades are located below the upper rotational flow blades and arranged around the main shaft; the upper overflowing disc is transversely fixed in the lower connector and comprises an upper main overflowing hole, an upper auxiliary overflowing hole and two needle valve holes. The axial bevel gear is in threaded connection with the bottom end of the main shaft, the radial bevel gears are matched with the axial bevel gear at 90 degrees respectively, and the two cams are fixedly connected with the radial bevel gears through key grooves respectively; the lower overflowing disc is transversely connected with the lower connector and located below the upper overflowing disc, the lower overflowing disc comprises a lower main overflowing hole and a lower auxiliary overflowing hole, the needle valves are arranged in the needle valve holes in a penetrating mode and located below the cam, circumferential rotation of the cam is converted into axial reciprocating motion of the needle valves, and the axial reciprocating motion of the needle valves enables the lower auxiliary overflowing hole to be opened and closed. The pressure of the drilling fluid is switched between a low point and a high point so as to generate periodic hydraulic pressure changes. The device relieves backing pressure and improves drilling efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of oil drilling, and in particular to a pressure generating device for drilling. Background Art

[0002] As oilfield exploration and development continue to deepen, drilling has gradually moved from shallow wells and wells that are easy to develop to deep wells and wells with complex structures. The number of extended-reach wells, horizontal wells and high-angle wells has gradually increased. The geological conditions of the drilled formations have become more and more complex, and there are more and more unstable factors underground. In particular, in the drilling operations of extended-reach wells and horizontal wells, there are common technical problems such as large directional friction, easy support pressure, and incomplete cleaning of the cuttings bed, which greatly restrict the speed and efficiency of drilling. At present, the mainstream technology to solve the problem of slow directional drilling speed caused by support pressure is mainly hydraulic oscillator technology. The hydraulic oscillator converts hydraulic energy into high-frequency vibration of key components in the oscillator through hydraulic action, thereby generating vibration along the axis of the drill bit assembly or drill pipe. This vibration can effectively change the friction form between the drill bit and the well wall, thereby reducing friction resistance and alleviating the support pressure problem.

[0003] The existing hydraulic oscillator power generating device mainly drives the moving valve to rotate through the screw rotor to achieve the periodic switching between the moving valve and the static valve, thereby realizing the periodic change of the pressure in the upper flow channel of the tool, and then driving the vibration unit to vibrate at high frequency. Due to the existence of the screw rubber parts, the use range and service life of the tool in high-temperature wells are limited; at the same time, the high-speed rotation of the moving valve and the static valve during work may cause the valve body to be severely worn and fail, or even the valve body may fall off and cause pump blockage; in addition, due to the eccentric structure of the screw stator and rotor structure, the lateral vibration of the oscillator is increased, which aggravates the overall vibration of the drill string and reduces the drilling efficiency. Therefore, how to change the current situation of poor drilling efficiency of hydraulic oscillators in the prior art and how to improve the service life and use effect of hydraulic oscillators have become urgent problems to be solved by those skilled in the art.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a pressure generating device for drilling, which adopts a fully mechanical metal structure design, can greatly improve the service life and operating temperature of the hydraulic oscillator, so that the hydraulic oscillator can efficiently relieve the support pressure during directional drilling of large displacement sections / long horizontal sections and high-angle wells, and has an excellent effect in improving the drilling pressure transmission efficiency.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A pressure generating device for drilling of the present invention comprises:

[0008] An upper joint having a hollow passage for introducing drilling fluid;

[0009] A connecting tube connected to the bottom end of the upper joint;

[0010] A lower joint having a hollow passage for conducting drilling fluid, wherein the upper joint, the connecting tube and the lower joint form a flow passage for the drilling fluid;

[0011] A cyclone is arranged in the connecting tube, and the cyclone comprises:

[0012] A fixed disk is threadedly connected to the connecting tube, and the fixed disk is provided with a central hole and a plurality of flow passages.

[0013] A main shaft is rotatably disposed in the central hole and extends downward.

[0014] A plurality of upper swirl blades are located below the flow passage and are arranged around the main shaft. The plurality of upper swirl blades are clockwise swirl blades when viewed from top to bottom.

[0015] A plurality of lower swirl blades, which are located below the plurality of upper swirl blades and are arranged around the main shaft, and the plurality of lower swirl blades are counterclockwise swirls when viewed from top to bottom;

[0016] An upper flow plate is transversely fixed in the lower joint and includes an upper main flow hole, an upper auxiliary flow hole and two needle valve holes;

[0017] A gear mechanism is arranged in the connecting cylinder, and the gear mechanism comprises:

[0018] Axial bevel gear, which is threadedly connected to the bottom end of the main shaft,

[0019] Two symmetrically distributed radial bevel gears, each of which is matched with the axial bevel gear at 90 degrees.

[0020] Two cams, each of which is key-grooved and fixedly connected to the radial bevel gear;

[0021] A lower flow plate, which is laterally connected to the lower joint and is located below the upper flow plate, wherein the lower flow plate includes a lower main flow hole and a lower auxiliary flow hole.

[0022] Two needle valves are respectively inserted into the needle valve holes and located below the cam. The circumferential rotation of the cam is converted into the axial reciprocating motion of the needle valve. The axial reciprocating motion of the needle valve causes the lower auxiliary flow hole to open and close, so that the drilling fluid pressure switches between the low point and the high point to produce periodic hydraulic pressure changes.

[0023] In the drilling pressure generating device, the upper joint, the connecting tube, the lower joint and the central axis of the main shaft are collinear.

[0024] In the drilling pressure generating device, the central axis of the connecting tube is a vertical axis, and the upper flow plate and the lower flow plate are both horizontally fixed in the lower joint.

[0025] In the drilling pressure generating device, the upper joint, the connecting tube and the lower joint are detachably connected in sequence.

[0026] In the drilling pressure generating device, eight flow passages of the same size are symmetrically distributed around the center hole, six upper swirl blades are all at an angle of 30° to the main axis, and six lower swirl blades are all at an angle of 15° to the main axis.

[0027] In the drilling pressure generating device, the cyclone further comprises:

[0028] a radial bearing comprising an inner ring which is interference fit with the spindle and an outer ring which is interference fit with the center hole,

[0029] A pressure cap is threadedly connected to the fixing plate.

[0030] In the drilling pressure generating device, the gear mechanism further comprises:

[0031] A support frame is supported on the upper flow plate, and radial bevel gears are rotatably connected to the support frame.

[0032] The support rib is a herringbone structure supported on the top of the support frame. A protective cap is provided on the top of the herringbone structure, and the upper end of the axial bevel gear passes through the protective cap.

[0033] A thrust bearing is arranged on the protective cap, and the thrust bearing comprises an upper thrust ring which is interference-fitted with the upper end of the axial bevel gear and a lower thrust ring which is interference-fitted with the protective cap.

[0034] In the drilling pressure generating device, the lower main flow hole and the upper main flow hole are of the same size, and the lower auxiliary flow hole and the upper auxiliary flow hole are of the same size.

[0035] In the pressure generating device for drilling, the two lower auxiliary flow holes are symmetrically arranged relative to the lower main flow hole, and the two upper auxiliary flow holes are symmetrically arranged relative to the upper main flow hole. Looking from top to bottom, the line connecting the lower auxiliary flow hole and the lower main flow hole is perpendicular to the line connecting the upper auxiliary flow hole and the upper main flow hole.

[0036] In the drilling pressure generating device, the needle valve comprises:

[0037] a valve body, which is threadedly connected to the needle valve hole,

[0038] a spring disposed in the valve body,

[0039] A gland is sealed on the top of the valve body to compress the spring, and the gland is threadedly connected to the needle valve hole.

[0040] A valve core passes through a spring to be installed in a valve body and both ends of the valve core extend out of the valve body, the upper end of the valve core contacts and cooperates with the cam line, and the lower end contacts and cooperates with the lower auxiliary flow hole surface, the circumferential rotation of the cam is converted into an axial reciprocating motion of the valve core, and the axial reciprocating motion of the valve core causes the lower auxiliary flow hole to open and close.

[0041] In the above technical scheme, the pressure generating device for drilling provided by the present invention has the following beneficial effects: the axial bevel gear is driven to rotate by the cyclone with a deceleration structure, the axial bevel gear is connected to the two radial bevel gears for rotation, a cam is designed on each radial bevel gear, the upper end of the needle valve is connected to the cam, the rotation of the cam drives the needle valve to make axial reciprocating motion, the lower end of the needle valve cooperates with the flow channel of the lower flow plate, and the flow channel of the lower flow plate is periodically opened and closed, thereby forming a high and low switching of the fluid pressure above the lower flow plate, forming the axial vibration of the entire friction reduction tool. The device adopts a fully mechanical metal structure design, with low manufacturing cost, long service life, high temperature resistance, and can meet the use requirements of efficient and low-cost sliding directional drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0043] Figure 1 A schematic structural diagram of a pressure generating device for drilling provided in an embodiment of the present invention.

[0044] Figure 2 A schematic structural diagram of a cyclone of a pressure generating device for drilling provided in an embodiment of the present invention.

[0045] Figure 3 A schematic diagram of the connection of a cyclone of a pressure generating device for drilling provided in an embodiment of the present invention.

[0046] Figure 4 A schematic structural diagram of a gear mechanism of a pressure generating device for drilling provided in an embodiment of the present invention.

[0047] Figure 5 A schematic diagram of the connection of a gear mechanism of a pressure generating device for drilling provided in an embodiment of the present invention.

[0048] Figure 6A schematic structural diagram of a needle valve of a pressure generating device for drilling provided in an embodiment of the present invention.

[0049] Figure 7 for Figure 6 A schematic cross-sectional view of AA of a needle valve of a pressure generating device for drilling provided by an embodiment of the present invention.

[0050] Figure 8 A schematic structural diagram of a lower flow plate of a pressure generating device for drilling provided in an embodiment of the present invention.

[0051] Fig. 9 for Figure 8 A schematic cross-sectional view of a lower flow plate BB of a pressure generating device for drilling provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0055] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0057] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0059] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0060] See also Figure 1-9 As shown, in one embodiment, a pressure generating device for drilling of the present invention comprises:

[0061] The upper joint 1 has a hollow channel for introducing drilling fluid;

[0062] A connecting tube 2 connected to the bottom end of the upper connector 1;

[0063] The lower joint 7 has a hollow passage for conducting drilling fluid, and the upper joint 1, the connecting tube 2 and the lower joint 7 form a flow passage for the drilling fluid;

[0064] The cyclone 3 is arranged in the connecting tube 2, and the cyclone 3 comprises:

[0065] The fixing plate 9 is threadedly connected to the connecting tube 2, and the fixing plate 9 is provided with a central hole and a plurality of flow passages.

[0066] A main shaft is rotatably disposed in the central hole and extends downward.

[0067] A plurality of upper swirl blades 11 are located below the flow passage and are arranged around the main shaft. The plurality of upper swirl blades 11 are clockwise swirl blades when viewed from top to bottom.

[0068] A plurality of lower swirl blades 12, which are located below the plurality of upper swirl blades 11 and are arranged around the main shaft, and the plurality of lower swirl blades 12 are counterclockwise swirls when viewed from top to bottom;

[0069] The upper flow plate 5 is transversely fixed in the lower joint 7, and includes an upper main flow hole 20, an upper auxiliary flow hole 21 and two needle valve holes 22;

[0070] The gear mechanism 4 is arranged in the connecting cylinder 2, and the gear mechanism 4 includes:

[0071] Axial bevel gear 16, which is threadedly connected to the bottom end of the main shaft,

[0072] Two symmetrically distributed radial bevel gears 17, each of which is matched with the axial bevel gear 16 at 90 degrees.

[0073] Two cams 18, which are respectively key-grooved and fixedly connected to the radial bevel gear 17;

[0074] The lower flow plate 6 is laterally connected to the lower joint 7 and is located below the upper flow plate 5. The lower flow plate 6 includes a lower main flow hole 29 and a lower auxiliary flow hole 30.

[0075] Two needle valves 23 are respectively inserted into the needle valve holes 22 and located below the cam 18. The circumferential rotation of the cam 18 is converted into the axial reciprocating motion of the needle valve 23. The axial reciprocating motion of the needle valve 23 causes the lower auxiliary flow hole 30 to open and close, so that the drilling fluid pressure switches between the low point and the high point to generate periodic hydraulic pressure changes.

[0076] In a preferred embodiment of the pressure generating device for drilling, the upper joint 1, the connecting tube 2, the lower joint 7 and the central axis of the main shaft are collinear.

[0077] In a preferred embodiment of the pressure generating device for drilling, the central axis of the connecting tube 2 is a vertical axis, and the upper flow plate 5 and the lower flow plate 6 are both horizontally fixed in the lower joint 7.

[0078] In a preferred embodiment of the pressure generating device for drilling, the upper joint 1, the connecting tube 2 and the lower joint 7 are detachably connected in sequence.

[0079] In a preferred embodiment of the pressure generating device for drilling, eight flow passages of the same size are symmetrically distributed around the center hole, six upper swirl blades 11 are at an angle of 30° to the main axis, and six lower swirl blades 12 are at an angle of 15° to the main axis.

[0080] In a preferred embodiment of the drilling pressure generating device, the cyclone 3 further comprises:

[0081] The radial bearing 10 comprises an inner ring which is interference-fitted with the main shaft and an outer ring which is interference-fitted with the center hole.

[0082] The pressure cap 8 is threadedly connected to the fixing plate 9.

[0083] In a preferred embodiment of the drilling pressure generating device, the gear mechanism 4 further comprises:

[0084] The support frame 19 is supported on the upper flow plate 5, and the radial bevel gears 17 are rotatably connected to the support frame 19.

[0085] The support rib 15 is a herringbone structure supported on the top of the support frame 19. A protective cap 14 is provided on the top of the herringbone structure. The upper end of the axial bevel gear 16 passes through the protective cap 14.

[0086] The thrust bearing 13 is disposed on the protective cap 14 , and includes an upper thrust ring that is interference-fitted with the upper end of the axial bevel gear 16 and a lower thrust ring that is interference-fitted with the protective cap 14 .

[0087] In a preferred embodiment of the drilling pressure generating device, the lower main flow hole 29 and the upper main flow hole 20 are of the same size, and the lower auxiliary flow hole 30 and the upper auxiliary flow hole 21 are of the same size.

[0088] In a preferred embodiment of the pressure generating device for drilling, the two lower auxiliary flow holes 30 are symmetrically arranged relative to the lower main flow hole 29, and the two upper auxiliary flow holes 21 are symmetrically arranged relative to the upper main flow hole 20. When viewed from top to bottom, the line connecting the lower auxiliary flow hole 30 and the lower main flow hole 29 is perpendicular to the line connecting the upper auxiliary flow hole 21 and the upper main flow hole 20.

[0089] In a preferred embodiment of the drilling pressure generating device, the needle valve 23 comprises:

[0090] The valve body 26 is threadedly connected to the needle valve hole 22.

[0091] The spring 27 is arranged in the valve body 26.

[0092] The pressure cover 25 is sealed and covers the top of the valve body 26 to compress the spring 27. The pressure cover 25 is threadedly connected to the needle valve hole 22.

[0093] The valve core 24 passes through the spring 27 to be installed in the valve body 26, and both ends of the valve core 24 extend out of the valve body 26. The upper end of the valve core 24 is in line contact with the cam 18, and the lower end is in surface contact with the lower auxiliary flow hole 30. The circumferential rotation of the cam 18 is converted into the axial reciprocating motion of the valve core 24, and the axial reciprocating motion of the valve core 24 causes the lower auxiliary flow hole 30 to open and close.

[0094] In one embodiment, the periodic hydraulic pressure variation is a sinusoidal periodic variation.

[0095] In one embodiment, a pressure generating device for drilling includes:

[0096] The upper joint 1 has a hollow channel for introducing drilling fluid;

[0097] A connecting tube 2 connected to the bottom end of the upper connector 1;

[0098] The lower joint 7 has a hollow channel for conducting drilling fluid. The upper joint 1, the connecting tube 2 and the lower joint 7 form a flow channel for the drilling fluid. The central axes of the upper joint 1, the connecting tube 2 and the lower joint 7 are collinear. The upper joint 1, the connecting tube 2 and the lower joint 7 are detachably connected in pairs, and further, are threadedly connected in pairs.

[0099] The cyclone 3 is arranged in the connecting tube 2, and the cyclone 3 comprises:

[0100] The fixing plate 9 is threadedly connected to the connecting tube 2. The fixing plate 9 is provided with a central hole and a plurality of flow passages. Eight flow passages of the same size surround the central hole.

[0101] The main shaft is rotatably arranged in the center hole and extends downward. Furthermore, the central axis of the main shaft is colinear with the central axis of the connecting tube 2, and the central axis of the connecting tube 2 is a vertical axis.

[0102] The radial bearing 10 comprises an inner ring which is interference-fitted with the main shaft and an outer ring which is interference-fitted with the center hole.

[0103] The pressure cap 8 is threadedly connected to the fixing plate 9.

[0104] A plurality of upper swirl blades 11 are located below the flow passage and are arranged around the main shaft. The plurality of upper swirl blades 11 are clockwise swirls when viewed from top to bottom. Furthermore, the plurality of upper swirl blades 1111 are all at an angle of 30° to the main shaft.

[0105] A plurality of lower swirl blades 12, which are located below the plurality of upper swirl blades 11 and are arranged around the main shaft, the plurality of lower swirl blades 12 are counterclockwise swirls when viewed from top to bottom, and further, the plurality of lower swirl blades 1212 are all at an angle of 15° to the main shaft;

[0106] The upper flow plate 5 is fixed in the lower joint 7 transversely, and includes an upper main flow hole 20, an upper auxiliary flow hole 21 and two needle valve holes 22; the upper flow plate 5 is fixed in the lower joint 7 horizontally.

[0107] The gear mechanism 4 is arranged in the connecting cylinder 2, and the gear mechanism 4 includes:

[0108] The support frame 19 is supported on the upper flow plate 5.

[0109] The support rib 15 is a herringbone structure supported on the top of the support frame 19, and a protective cap 14 is provided on the top of the herringbone structure.

[0110] The upper end of the axial bevel gear 16 passes through the protective cap 14 and is threadedly connected to the bottom end of the main shaft.

[0111] The thrust bearing 13 is arranged on the protective cap 14, and the thrust bearing 13 includes an upper thrust ring which is interference-fitted with the upper end of the axial bevel gear 16 and a lower thrust ring which is interference-fitted with the protective cap 14.

[0112] Two symmetrically distributed radial bevel gears 17, each of which is rotatably connected to the support frame 19 and cooperates with the axial bevel gear 16 at 90 degrees.

[0113] Two cams 18, which are respectively key-grooved and fixedly connected to the radial bevel gear 17;

[0114] The lower flow plate 6 is laterally connected to the lower joint 7 and is located below the upper flow plate 5. Further, it is threadedly connected to the lower joint 7 and remains horizontal. The lower flow plate 6 includes a lower main flow hole 2929 and a lower auxiliary flow hole 3030. Looking from top to bottom, the lower auxiliary flow hole 30 and the upper auxiliary flow hole 21 are arranged at 90 degrees. The two lower auxiliary flow holes 30 are symmetrically arranged relative to the lower main flow hole 29. The lower main flow hole 29 and the upper main flow hole 20 are of the same size, and the lower auxiliary flow hole 30 and the upper auxiliary flow hole 21 are of the same size.

[0115] Two needle valves 23, each of which is inserted into the needle valve hole 22 and is located below the cam 18, and the needle valve 23 includes:

[0116] The valve body 26 is threadedly connected to the needle valve hole 22.

[0117] The spring 27 is arranged in the valve body 26.

[0118] The pressure cover 25 is sealed and covers the top of the valve body 26 to compress the spring 27. The pressure cover 25 is threadedly connected to the needle valve hole 22.

[0119] The valve core 24 passes through the spring 27 to be installed in the valve body 26, and both ends of the valve core 24 extend out of the valve body 26. The upper end of the valve core 24 is in line contact with the cam 18, and the lower end is in surface contact with the lower auxiliary flow hole 30. The circumferential rotation of the cam 18 is converted into the axial reciprocating motion of the valve core 24. The axial reciprocating motion of the valve core 24 causes the lower auxiliary flow hole 30 to open and close, so that the drilling fluid pressure switches between the low point and the high point to produce periodic hydraulic pressure changes. When the lower auxiliary flow hole 30 is opened, the drilling fluid pressure is at a low point, and when the lower auxiliary flow hole 30 is closed, the drilling fluid pressure is at a high point.

[0120] In one embodiment, a pressure generating device for drilling is composed of an upper joint 1, a connecting tube 2, a cyclone 3, a gear mechanism 4, a needle valve 23, an upper flow plate 5, a lower flow plate 6 and a lower joint 7. The cyclone 3 includes a pressure cap 8, a fixed plate 9, a radial bearing 10, an upper swirl blade 11, and a lower swirl blade 12. The fixed plate 9 is connected to the connecting tube 2 by threads. The fixed plate 9 is provided with 8 flow passages of the same size. The outer ring of the radial bearing 10 is interference fit with the fixed plate 9, and the inner ring of the radial bearing 10 is interference fit with the main shaft of the cyclone 3. The pressure cap 8 is connected to the fixed plate 9 by threads. The pressure cap 8 prevents the radial bearing 10 from erosion failure. The six upper swirl blades 11 are all at an angle of 30° to the main shaft, and are clockwise swirls when viewed from top to bottom. The six lower swirl blades 12 are all at an angle of 15° to the main shaft, and are counterclockwise swirls when viewed from top to bottom. Since the counterclockwise force generated by the lower swirl blades 12 can offset part of the clockwise force generated by the upper swirl blades 11, the cyclone 3 will not significantly increase the rotation speed of the cyclone as the drilling fluid discharge increases, and the lower swirl blades 12 play a role in stabilizing the rotation speed of the cyclone 3. The gear mechanism is mainly composed of an axial bevel gear 16, a radial bevel gear 17, a cam 18, a protective cap 14, an axial thrust bearing 13, a support rib 15, and a support frame 19. The upper end of the axial bevel gear 16 is connected to the lower end of the cyclone 3 through a thread, the thrust bearing 13 is an axial thrust bearing, the upper thrust ring of the thrust bearing 13 is interference fit with the main shaft of the axial bevel gear 16, the lower thrust ring is interference fit with the protective cap, the protective cap 14 is fixed on the support rib 15, and the support rib 15 is fixed on the support frame 19. The protective cap 14 not only supports the axial bevel gear 16, but also protects the axial bevel gear 16 and the radial bevel gear 17 from erosion by high-pressure and high-speed fluid. Two radial bevel gears 17 are arranged in a symmetrical distribution, respectively with the axial The bevel gears 16 are matched at 90 degrees, and a cam 18 is arranged on each radial bevel gear 17. The cam 18 is fixedly connected to the radial bevel gear 17 through a keyway. The gear end of the radial bevel gear 17 is matched with the axial bevel gear. The main shaft end is fixed on the support frame 19, and the support frame 19 is fixed on the upper flow disc 5. The upper flow disc 5 is fixed on the lower joint 7 through a threaded connection. An upper main flow hole 20 and two upper auxiliary flow holes 21 are arranged on the upper flow disc 5. At the same time, two needle valve holes 22 are arranged on the upper flow disc 5, and the needle valve hole 22 is used to fix the needle valve 23. The needle valve 23 is mainly composed of a valve core 24, a pressure cover 25, a valve body 26, a spring 27 and an O-ring 28. The spring 27 is installed in the valve body 26. The valve core 24 is installed in the valve body 26 through the spring 27. The valve body 26 is connected to the needle valve hole 22 in the upper flow disk 5 through a thread. The pressure cover 25 is connected to the needle valve hole 22 in the upper flow disk 5 through a thread. The pressure cover 25 not only compresses the spring 27, but also seals the needle valve cavity. The upper end of the valve core 24 is in line contact with the cam 18 on the radial bevel gear 17, and the lower end is in surface contact with the lower auxiliary flow hole 30 on the lower flow disk 6.The lower flow plate 6 is provided with a lower main flow hole 29 and two lower auxiliary flow holes 30, and is connected to the lower joint 7 by threads. The two lower auxiliary flow holes 30 are symmetrically arranged. The lower main flow hole 29 in the lower flow plate 6 and the upper main flow hole 20 in the upper flow plate 5 are of the same size. The lower auxiliary flow holes 30 in the lower flow plate 6 and the upper auxiliary flow holes 21 in the upper flow plate 5 are of the same size. After the lower flow plate 6 is fixed, looking from top to bottom, the two lower auxiliary flow holes 30 and the two upper auxiliary flow holes 21 in the upper flow plate 5 are arranged at 90°.

[0121] When the drilling pressure generating device is working: looking from top to bottom, when the high-pressure drilling fluid flows through the upper joint, it first flows through the upper swirl blade 11 of the cyclone 3. Since the upper swirl blade 11 is at a 30° clockwise angle with the main shaft, the cyclone 3 generates a clockwise force. The drilling fluid flows through the lower swirl blade 12. Since the lower swirl blade 12 is at a 15° counterclockwise angle with the main shaft, the cyclone 3 generates a counterclockwise force. Since the counterclockwise force generated by the lower swirl blade 12 is smaller than the clockwise force generated by the upper swirl blade 11, the cyclone 3 rotates at a high speed under the action of the clockwise force, and drives the axial bevel gear 16 to rotate at a high speed. The radial bevel gear 17 and the axial bevel gear 16 are 90° gear matching, so the high-speed rotation of the axial bevel gear 16 becomes the high-speed rotation of the radial bevel gear 17. The cam 18 is fixed on the radial bevel gear 17. The cam 18 As the radial bevel gear 17 rotates at high speed, the valve core 24 of the needle valve 23 is in line contact with the cam 18, so the circumferential rotation of the cam 18 is converted into the axial reciprocating motion of the valve core 24 of the needle valve 23, and the lower end of the valve core 24 is in surface contact with the lower auxiliary flow hole 30 of the lower flow disk 6. The axial reciprocating motion of the valve core 24 causes the lower auxiliary flow hole 30 of the lower flow disk 6 to open and close. When the lower auxiliary flow hole 30 of the lower flow disk 6 is opened, the drilling fluid pressure is at a low point. When the lower auxiliary flow hole 30 of the lower flow disk 6 is closed, the drilling fluid pressure is at a high point. As the lower auxiliary flow hole 30 of the lower flow disk 6 is opened and closed, the drilling fluid pressure also switches between the low point and the high point, resulting in periodic hydraulic pressure changes. The periodic pressure fluctuations are converted into periodic vibration force and tool amplitude through the hydraulic oscillator vibration short section, which drives the drill string close to the well wall to move and relieve the drag pressure.

[0122] Finally, it should be noted that the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of the present application.

[0123] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A pressure generating device for drilling, characterized in that: These include, An upper joint having a hollow passage for introducing drilling fluid; A connecting tube connected to the bottom end of the upper joint; A lower joint having a hollow passage for conducting drilling fluid, wherein the upper joint, the connecting tube and the lower joint form a flow passage for the drilling fluid; A cyclone is arranged in the connecting tube, and the cyclone comprises: A fixed disk is threadedly connected to the connecting tube, and the fixed disk is provided with a central hole and a plurality of flow passages. A main shaft is rotatably disposed in the central hole and extends downward. A plurality of upper swirl blades are located below the flow passage and are arranged around the main shaft. The plurality of upper swirl blades are clockwise swirl blades when viewed from top to bottom. A plurality of lower swirl blades, which are located below the plurality of upper swirl blades and are arranged around the main shaft, and the plurality of lower swirl blades are counterclockwise swirls when viewed from top to bottom; An upper flow plate is transversely fixed in the lower joint and includes an upper main flow hole, an upper auxiliary flow hole and two needle valve holes; A gear mechanism is arranged in the connecting cylinder, and the gear mechanism comprises: Axial bevel gear, which is threadedly connected to the bottom end of the main shaft, Two symmetrically distributed radial bevel gears, each of which is matched with the axial bevel gear at 90 degrees. Two cams, each of which is key-grooved and fixedly connected to the radial bevel gear; A lower flow plate, which is laterally connected to the lower joint and is located below the upper flow plate, wherein the lower flow plate includes a lower main flow hole and a lower auxiliary flow hole. Two needle valves are respectively inserted into the needle valve holes and located below the cam. The circumferential rotation of the cam is converted into the axial reciprocating motion of the needle valve. The axial reciprocating motion of the needle valve causes the lower auxiliary flow hole to open and close, so that the drilling fluid pressure switches between the low point and the high point to produce periodic hydraulic pressure changes.

2. A drilling pressure generating device according to claim 1, characterized in that: The central axes of the upper joint, the connecting tube, the lower joint and the main shaft are collinear.

3. A drilling pressure generating device according to claim 2, characterized in that: The central axis of the connecting cylinder is a vertical axis, and the upper flow plate and the lower flow plate are both horizontally fixed in the lower joint.

4. A drilling pressure generating device according to claim 1, characterized in that: The upper joint, the connecting tube and the lower joint are detachably connected in sequence.

5. A drilling pressure generating device according to claim 1, characterized in that: Eight flow channels of the same size are symmetrically distributed around the center hole, the six upper swirl blades are all at an angle of 30° to the main axis, and the six lower swirl blades are all at an angle of 15° to the main axis.

6. A drilling pressure generating device according to claim 1, characterized in that: The cyclone also includes, a radial bearing comprising an inner ring which is interference fit with the spindle and an outer ring which is interference fit with the center hole, A pressure cap is threadedly connected to the fixing plate.

7. A drilling pressure generating device according to claim 1, characterized in that: The gear mechanism also includes, A support frame is supported on the upper flow plate, and radial bevel gears are rotatably connected to the support frame. The support rib is a herringbone structure supported on the top of the support frame. A protective cap is provided on the top of the herringbone structure, and the upper end of the axial bevel gear passes through the protective cap. A thrust bearing is arranged on the protective cap, and the thrust bearing comprises an upper thrust ring which is interference-fitted with the upper end of the axial bevel gear and a lower thrust ring which is interference-fitted with the protective cap.

8. A drilling pressure generating device according to claim 1, characterized in that: The lower main flow hole is consistent with the upper main flow hole in size, and the lower auxiliary flow hole is consistent with the upper auxiliary flow hole in size.

9. A drilling pressure generating device according to claim 1, characterized in that: The two lower auxiliary flow holes are symmetrically arranged relative to the lower main flow hole, and the two upper auxiliary flow holes are symmetrically arranged relative to the upper main flow hole. Looking from top to bottom, the line connecting the lower auxiliary flow hole and the lower main flow hole is perpendicular to the line connecting the upper auxiliary flow hole and the upper main flow hole.

10. A drilling pressure generating device according to claim 1, characterized in that: The needle valve comprises: a valve body, which is threadedly connected to the needle valve hole, a spring disposed in the valve body, A gland is sealed on the top of the valve body to compress the spring, and the gland is threadedly connected to the needle valve hole. A valve core passes through a spring to be installed in a valve body and both ends of the valve core extend out of the valve body, the upper end of the valve core contacts and cooperates with the cam line, and the lower end contacts and cooperates with the lower auxiliary flow hole surface, the circumferential rotation of the cam is converted into an axial reciprocating motion of the valve core, and the axial reciprocating motion of the valve core causes the lower auxiliary flow hole to open and close.

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