Axial flow plate wing type underground power drilling tool, motor assembly and drilling tool using method

Abstract

The invention discloses an axial flow plate wing type downhole power drilling tool, a motor assembly and a drilling tool using method. The power drilling tool comprises a motor assembly, a sealing assembly and a speed reduction assembly, the sealing assembly is connected with the motor assembly, and rotating speed and torque are transmitted to a drill bit through a transmission shaft. The motor assembly comprises an upper joint and a stator which are connected with each other, a rotor arranged in an elliptical inner hole of the stator, and input and output shunting discs arranged at two ends of the rotor; the rotor comprises a rotor core shaft, a plurality of spokes are arranged on the rotor core shaft, and plate wing assemblies are arranged in grooves of the spokes; the plate wing assembly comprises a spring and a plate wing, and the plate wing is connected with the inner wall of the oval inner hole under the elastic force effect of the spring. Two groups of shunting holes are formed in each of the input shunting disc and the output shunting disc in a staggered manner, so that the trend of liquid in the rotor is guided, and the rotor is driven to rotate. The hydraulic energy of the drilling fluid can be converted into mechanical power to be output, and the hydraulic energy conversion device has the advantages of being compact in structure, resistant to high temperature, low in speed and large in torque output and low in production and maintenance cost.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas industrial drilling, and particularly relates to an axial flow vane type downhole motor, a motor assembly and a method for using the drill. Background Art

[0002] A downhole motor is a downhole drill that converts the energy of drilling fluid into the power for rock breaking during drilling. It plays a huge role in improving drilling speed, reducing drilling costs, and achieving directional control of the wellbore trajectory. Currently, there are mainly three types of downhole motors developed and utilized at home and abroad, namely positive displacement motors, turbine motors, and electric motors.

[0003] The electric motor appeared relatively early. It has a high output speed, a complex reducer structure, poor reliability, high requirements for the insulation and sealing performance of the downhole motor, and a low service life. In the 1940s of the last century, it was gradually phased out with the emergence of turbine motors.

[0004] Turbine motors were widely used in the last century. They have the advantages of high temperature resistance, no lateral vibration, and stable operation. However, their disadvantages are also very obvious. The characteristics of high speed and low torque are not suitable for drilling conditions. Problems such as large length, soft torque characteristics, and on-site application, as well as relatively high manufacturing and maintenance costs, limit their application scope. Therefore, with the emergence of positive displacement motors, the application scope of turbine motors has been limited.

[0005] Positive displacement motors are currently the most widely used downhole motors. Because they have characteristics such as low speed and high torque, and hard torque characteristics, they are very suitable for drilling operations. Therefore, they are currently the most widely used downhole motors. Summary of the Invention

[0006] The inventors of the present application found that for the widely used positive displacement motors currently, due to the need for a large number of rubber components in the stator housing of the drill, restricted by the temperature characteristics of rubber, they are not suitable for high-temperature wells and are very sensitive to oil-based drilling fluids, and are restricted in use in high-temperature and high-pressure wells. Due to the poor performance of positive displacement motors in terms of high temperature resistance, their service life is low, production and maintenance costs are high, environmental adaptability is poor, and applicability is poor.

[0007] In view of the above problems, the present invention is proposed to provide an axial flow vane type downhole motor, a motor assembly and a method for using the drill that overcome the above problems or at least partially solve the above problems.

[0008] An embodiment of the present invention provides an axial flow vane type motor assembly, including: the motor assembly includes an upper sub and a stator connected to each other, a rotor disposed in the elliptical inner hole of the stator, an input diverter disk and an output diverter disk respectively disposed at the upper and lower ends of the rotor;

[0009] The rotor includes a rotor core shaft, on which a plurality of spokes are provided, and a blade assembly is provided in the groove of each spoke; the blade assembly includes a spring and a blade, and the blade is connected to the inner wall of the elliptical inner hole under the action of the spring force;

[0010] Both the input diverter disk and the output diverter disk are provided with two groups of diversion holes, and the diversion holes of the input diverter disk and the output diverter disk are staggered in position to guide the flow direction of the liquid in the rotor and drive the rotor to rotate.

[0011] In some alternative embodiments, the number of spokes on the rotor core shaft is 8, and they are evenly arranged in a circle.

[0012] In some alternative embodiments, the blade assembly further includes a sealing strip, which is installed in the sealing groove of the spoke.

[0013] The sealing strip is made of a high-temperature resistant material; the blade is made of a soft metal material or has a soft metal electroplated surface; the spring is a compression spring.

[0014] In some alternative embodiments, both the upper and lower ends of the stator are provided with bosses and external threads; positioning pins are provided on the bosses; the positioning pin on the upper boss cooperates with the positioning groove on the input diverter disk, and the positioning pin on the lower boss cooperates with the positioning groove on the output diverter disk.

[0015] In some alternative embodiments, a first gear output shaft is provided at the lower end of the rotor to output rotational speed and torque.

[0016] An embodiment of the present invention further provides an axial flow blade type downhole motor drill, including: a sealing assembly and the motor assembly as described in any one of the above;

[0017] The sealing assembly is connected to the motor assembly and is used to transmit rotational speed and torque to the drill bit through a transmission shaft.

[0018] In some alternative embodiments, a reduction assembly is further included between the motor assembly and the sealing assembly, and the reduction assembly includes: an internal gear ring, a plurality of planet gears, a planet gear carrier, and a sun gear;

[0019] The internal gear ring is connected to the lower end of the stator, and its inner wall has teeth that mesh with the planet gears;

[0020] The sun gear is arranged in the middle of the plurality of planet gears and meshes with each planet gear respectively, and the sun gear is connected to the rotor in the motor assembly;

[0021] The planet gears are connected to the planet gear carrier, and the planet gear carrier is provided with a second gear output shaft to output rotational speed and torque.

[0022] In some alternative embodiments, the sealing assembly includes a sealing body and a transmission shaft disposed within the sealing body, with a bearing provided between the transmission shaft and the sealing body.

[0023] The sealing body includes an outer cylinder and a limiting joint connected in sequence. The outer cylinder is connected to the internal gear ring in the reduction assembly. The limiting joint is provided with a transmission shaft hole and is in sealing cooperation with the transmission shaft through the transmission shaft hole.

[0024] The lower end of the transmission shaft is provided with an output joint to connect to the drill bit.

[0025] The bearing includes a thrust bearing and a radial bearing.

[0026] The embodiment of the present invention also provides the application of the axial flow vane type motor assembly as described above and the axial flow vane type downhole motor as described above during the drilling process.

[0027] In some alternative embodiments, the usage method of the axial flow vane type downhole motor includes:

[0028] Install the axial flow vane type downhole motor at the bottom of the drilling string, and connect the drill bit to the bottom of the axial flow vane type downhole motor.

[0029] Lower the axial flow vane type downhole motor to the bottom of the well. The drilling fluid enters the interior of the rotor through the drilling string and the input diverter plate in the motor assembly, driving the rotor to rotate. The rotational speed and torque output by the rotor are transmitted to the transmission shaft in the sealing assembly through the reduction assembly and output to the drill bit through the transmission shaft, driving the drill bit to rotate.

[0030] In some alternative embodiments, the drilling fluid enters the interior of the rotor through the drilling string and the input diverter plate in the motor assembly, driving the rotor to rotate, including:

[0031] The drilling fluid in the drilling string enters the interior of the rotor through the diversion holes of the input diverter plate in the motor assembly.

[0032] Under the action of the input diverter plate and the output diverter plate, the interior of the rotor with multiple vanes is divided into two high-pressure chambers and two low-pressure chambers.

[0033] Under the pressure difference between the high-pressure chamber and the low-pressure chamber, the vanes are pushed to rotate.

[0034] In some alternative embodiments, it further includes:

[0035] The drilling string rotates driven by a power source, driving the axial flow vane type downhole motor to rotate. The drill bit rotates under the dual drive of the drilling string and the axial flow vane type downhole motor.

[0036] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0037] The axial flow vane type motor assembly provided by the embodiments of the present invention shunts the drilling fluid by arranging an input shunt disc and an output shunt disc, so that two high-pressure chambers and two low-pressure chambers are formed inside the rotor of the motor assembly, and the rotor is pushed to rotate under the pressure difference between the high-pressure chamber and the low-pressure chamber; and the inner cavity of the stator is set to be elliptical, and further, due to the difference in the lengths of the abutting vanes, it is ensured that sufficient driving force can be generated when the pressure difference acts on the vanes; this motor assembly directly does work through hydraulic pressure, has a large power density, a small volume, good hole deviation ability and a small curvature radius during drilling. This motor assembly does not need to use rubber material components and can be made of high-temperature resistant materials, so it can be well applied to high-temperature wells, improving the high-temperature resistance performance of the drill string, extending its service life, reducing production and maintenance costs, and having strong environmental adaptability and good applicability of the motor assembly.

[0038] The axial flow vane type downhole motor provided by the embodiments of the present invention includes the above-mentioned motor assembly and a sealing assembly. Since its motor assembly directly does work through hydraulic pressure, it has a large power density, a small volume, good hole deviation ability and a small curvature radius during drilling. The components of this downhole motor do not need to use rubber materials and can be made of high-temperature resistant materials, so it can be well applied to high-temperature wells, improving the high-temperature resistance performance of the drill string, extending its service life, reducing production and maintenance costs, and having strong environmental adaptability and good applicability of the downhole motor.

[0039] Other features and advantages of the present invention will be described in the following description, and in part, will be obvious from the description, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings.

[0040] The technical solutions of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0041] The drawings are used to provide a further understanding of the present invention and constitute a part of the description. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0042] Figure 1 It is the structure assembly drawing of the axial flow vane type motor assembly in Embodiment 1 of the present invention;

[0043] Figure 2 It is the exploded view of the axial flow vane type motor assembly in Embodiment 1 of the present invention;

[0044] Figure 3 It is one of the schematic diagrams of the stator structure in Embodiment 1 of the present invention;

[0045] Figure 4 It is the second schematic diagram of the stator structure in the first embodiment of the present invention;

[0046] Figure 5 It is the schematic diagram of the rotor structure in the first embodiment of the present invention;

[0047] Figure 6 It is the cross-sectional view of the rotor structure in the first embodiment of the present invention;

[0048] Figure 7 It is the schematic diagram of the structure of the input diverter disk in the first embodiment of the present invention;

[0049] Figure 8 It is the schematic diagram of the structure of the output diverter disk in the first embodiment of the present invention;

[0050] Figure 9 It is the schematic diagram of the motor input in the first embodiment of the present invention;

[0051] Figure 10 It is the schematic diagram of the motor output in the first embodiment of the present invention;

[0052] Figure 11 It is the first schematic diagram of the motor operation in the first embodiment of the present invention;

[0053] Figure 12 It is the second schematic diagram of the motor operation in the first embodiment of the present invention;

[0054] Figure 13 It is the installation position diagram of the axial flow vane type downhole motor drill in the second embodiment of the present invention;

[0055] Figure 14 It is the overall structure diagram of the axial flow vane type downhole motor drill in the second embodiment of the present invention;

[0056] Figure 15 It is the schematic diagram of the structure of a part of the speed reduction assembly in the second embodiment of the present invention;

[0057] Figure 16 It is the schematic diagram of the structure of another part of the speed reduction assembly in the second embodiment of the present invention;

[0058] Figure 17 It is the assembly diagram of the seal assembly structure in the second embodiment of the present invention;

[0059] Figure 18 It is the exploded view of the seal assembly in the second embodiment of the present invention;

[0060] Figure 19 It is the flow chart of the usage method of the axial flow vane type downhole motor drill in the third embodiment of the present invention. Detailed implementation manners

[0061] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0062] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0063] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "connection" 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 a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. 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 situations.

[0064] To address the deficiencies of current downhole motor tools, the present invention provides an axial flow vane type downhole motor tool. This device is connected to the bottom of the drilling string and is connected to a drill bit at the bottom. Plate vanes are placed in the rotor slots and extend under the action of springs to contact and fit with the inner wall of the stator, forming multiple relatively sealed spaces. The stator is an elliptical structure. When drilling fluid enters the motor through the flow dividing plate, it acts on the plate vanes to form a force that pushes the rotor to rotate around the axis, outputting rotational speed and torque. Further, it is output after passing through a speed reduction and transmission mechanism, driving the drill bit to rotate and break rocks, and finally converting the hydraulic energy of the drilling fluid into mechanical power output. Compared with current downhole motor tools, it has the characteristics of being structurally compact, high temperature resistant, low speed and large torque output, and lower production and maintenance costs.

[0065] Embodiment 1

[0066] Embodiment 1 of the present invention provides an axial flow vane type motor assembly, and its structural assembly diagram and exploded diagram are as shown in Figure 1 、 Figure 2 and includes: an upper sub 01 and a stator 02 that are connected to each other, a rotor 04 disposed in the elliptical inner hole of the stator, and an input flow dividing plate 03 and an output flow dividing plate 05 respectively disposed at the upper and lower ends of the rotor.

[0067] The rotor 04 includes a rotor core shaft 041. A plurality of spokes are provided on the rotor core shaft 041, and a vane assembly is provided in the groove of each spoke; the vane assembly includes a spring 042 and a vane 044, and the vane is connected to the inner wall of the elliptical inner hole under the action of the spring force.

[0068] Both the input diverter disc and the output diverter disc are provided with two sets of diversion holes, and the diversion holes of the input diverter disc and the output diverter disc are arranged in a staggered manner to guide the flow direction of the liquid in the rotor and drive the rotor to rotate.

[0069] In some alternative embodiments, the assembly relationship of the motor assembly is as Figure 1 shown: The upper joint 01 is threadedly connected to the bottom of the drill string, and the lower part is connected to the stator 02. A diverter disc 03 is placed in the middle of the two. The four grooves of the diverter disc 03 cooperate with the four positioning pins on the upper end face of the stator 02. Similarly, the output diverter disc 05 is installed at the lower end of the stator 02, and the rotor 04 is installed inside the stator 02 and can rotate.

[0070] In some alternative embodiments, the structure of the stator 02 is as Figure 3 and Figure 4 shown, Figure 3 and Figure 4 are views from different perspectives respectively. Both the upper and lower ends of the stator are provided with bosses and external threads; positioning pins are provided on the bosses; the positioning pins on the upper boss cooperate with the positioning grooves on the input diverter disc, and the positioning pins on the lower boss cooperate with the positioning grooves on the output diverter disc. For example Figure 2 shown, a set of external threads and bosses are respectively machined at the upper and lower ends of the stator 02. There are four positioning pins on each boss. The inner diameter of the stator 02 is an elliptical structure, the inner wall is smooth, and it has a very high surface hardness.

[0071] In some alternative embodiments, the three-dimensional structure of the rotor 04 is shown in Figure 5 shown, and the structure of a cross-section is as Figure 6 shown, including: a rotor core shaft 041. A plurality of spokes are provided on the rotor core shaft 041, and a vane assembly is provided in the groove of each spoke; the vane assembly includes a spring 042 and a vane 044, and the vane is connected to the inner wall of the elliptical inner hole under the action of the spring force. The output end of the rotor 04 is a gear shaft structure to facilitate the output and transmission of torque.

[0072] The rotor core shaft 041 is the main body of the rotor 04 and is a long shaft-shaped structure including a plurality of spokes. Optionally, the number of spokes on the rotor core shaft is 8, and they are evenly arranged in a circumferential manner. The vane assembly further includes a sealing strip, which is installed in the sealing groove in the groove of the spoke; the sealing strip is made of a high-temperature resistant material. See Figure 5As shown, a groove is machined on each spoke, and a plurality of springs 042, a plate wing 044, and two sealing strips 043 are placed in the groove. Among them, the plate wing 044 is made of soft metal or has its surface electroplated with soft metal. The spring 042 is a compression spring, and the sealing strip 043 is made of metal or other high-temperature wear-resistant materials to seal the gap between the plate wing 044 and the groove of the rotor core shaft 041. When there is no external force, the plate wing 044 will extend under the thrust of the spring 042, and when subjected to an external force, the plate wing 044 will also overcome the spring 042 and move into the groove.

[0073] In some alternative embodiments, the structural diagrams of the input diverter disk and the output diverter disk are as Figure 7 and Figure 8 shown. Two sets of diversion holes are provided on each disk, and the diversion holes of the input diverter disk and the output diverter disk are arranged in a staggered manner to guide the flow direction of the liquid in the rotor and drive the rotor to rotate.

[0074] The input diverter disk is of a disk-shaped structure, with two diversion holes machined to guide the drilling fluid into the interior of the motor. Four grooves are machined on the side to cooperate with the positioning pins on the upper end face of the stator 02 to fix the relative positions of the diverter disk 03 and the stator 02. The output diverter disk 05 has a similar structure to the input diverter disk 03, and the diversion holes of the two are staggered by 90°. An additional shaft hole is left in the middle of the output diverter disk.

[0075] Based on the above composition structure, the working principle of the motor assembly is as follows: The drilling fluid enters the interior of the motor through the input diverter disk 03 and then flows out through the output diverter disk 05. Due to the diversion effect of the diverter disks 03 and 05 (as Figure 9 and Figure 10 shown), the interior of the motor is divided into two high-pressure chambers and two low-pressure chambers.

[0076] The schematic diagram of the operation of the motor assembly is as Figure 11 and Figure 12 shown. Among them, the liquid inlets A, A' and the liquid outlets B, B' divide the motor volume chamber into four chambers. The chambers connected to the liquid inlets are high-pressure chambers, and the chambers connected to the liquid outlets are low-pressure chambers. As Figure 11 shown, taking the liquid inlet A and the liquid outlet B' as an example, when the drilling fluid flows in through the liquid inlet A, at this time, the plate wings 2 and 3, and the plate wings 2 and 1 form two high-pressure chambers. The drilling fluid acts on the plate wings to form four thrusts. The thrust acting on the right side of the plate wing 3 forms a counterclockwise thrust denoted as F 3L , the thrust acting on the left side of the plate wing 2 forms a clockwise thrust denoted as F 2R , the thrust acting on the right side of the plate wing 2 forms a counterclockwise thrust F 2L , and the thrust acting on the left side of the plate wing 1 forms a clockwise thrust F 1R ; because the forces acting on the left and right sides of the plate wing 2 are basically equal and can cancel each other out, that is, F 2L = F2R At this time, the resultant force is the clockwise force formed by the left side of the blade 1 minus the counterclockwise force formed by the right side of the blade 3, that is, F 1R -F 3L Because at this time, the blade 1 is located on the major axis of the ellipse of the stator 02, and the blade 3 is on the minor axis of the ellipse of the stator 02. The acting area of the blade 1 is larger than that of the blade 3, that is, F 1R -F 3L =F R >0, the magnitude of F R is determined by the difference between the major and minor semi-axes of the stator 02. For the convenience of analysis, the pressures of the drain ports B and B' are set to 0. At this time, the resultant force formed by the inlet port A and the drain port B' is F R Similarly, the resultant force F will be formed by the inlet port A' and the drain port B R’ , and its magnitude and direction are the same as those of F R . Finally, the resultant force F composed of F R and F R’ drives the rotor 02 to rotate clockwise until Figure 12 as shown. At this time, the new resultant force F is also a clockwise force. Continuing to rotate, it appears again Figure 11 as shown. Repeating the above process, the rotor 02 always rotates clockwise.

[0077] An axial-flow blade-type motor assembly provided in Embodiment 1 of the present invention can be realized by using high-temperature-resistant materials without using rubber material components. It can be well applied to high-temperature wells, improving the high-temperature resistance performance of the drilling tool, extending its service life, reducing production and maintenance costs, and having strong environmental adaptability and good applicability.

[0078] Embodiment 2

[0079] Embodiment 2 of the present invention provides an axial-flow blade-type downhole motor drill. For the installation position diagram of the downhole motor drill, see Figure 13 as shown. A drill bit can be connected below the downhole motor drill. For the structure of the downhole motor drill, see Figure 14 as shown. An optional structure of the downhole motor drill includes: a sealing assembly and the motor assembly as described in Embodiment 1 above; the sealing assembly is connected to the motor assembly for transmitting the rotational speed and torque to the drill bit through a transmission shaft.

[0080] In some optional embodiments, the axial-flow blade-type downhole motor drill further includes: a reduction assembly disposed between the motor assembly and the sealing assembly. That is, another optional structure of the downhole motor drill includes a sealing assembly, a reduction assembly, and the motor assembly as described in Embodiment 1 above.

[0081] For the mechanism of the reduction assembly, see Figure 15 and Figure 16As shown in the figure, it includes: an internal gear ring 06, multiple planet gears 09, a planet gear carrier 10, and a sun gear 08; among them, the internal gear ring 06 is connected to the lower end of the stator 02, and its inner wall has teeth and meshes with the planet gears 09; the sun gear 08 is arranged in the middle of the multiple planet gears 09 and meshes with each planet gear respectively, and the sun gear 08 is connected to the rotor 04 in the motor assembly; the planet gears 09 are connected to the planet gear carrier 10, and the planet gear carrier 10 is provided with a second gear output shaft to output rotational speed and torque.

[0082] In some alternative embodiments, the upper end of the internal gear ring 06 is machined with threads and connected to the lower end of the stator 02 of the motor assembly, and the lower end is machined with threads and connected to the outer cylinder 11 of the sealed transmission assembly. Its inner wall is machined with teeth, and two 07 limit rings are threadedly connected to both ends of the teeth. The inner wall meshes with three planet gears 09. The lower ends of the planet gears 09 are installed on the planet carrier 10 with pins. The output end of the planet carrier 10 is a gear shaft that transmits torque and rotational speed. The sun gear 08 meshed in the middle of the three planet gears 09 is machined with internal teeth at its upper end and meshes and transmits power with the output shaft of the rotor 04 of the motor assembly.

[0083] Based on the above composition structure, the working principle of the reduction assembly is as follows: the motor assembly located in the upper part outputs torque, which is transmitted to the sun gear 08 through the rotor core shaft 041. The sun gear 08 rotates and drives the three planet gears 09 to operate. At this time, the planet gears 09, the sun gear 08, and the internal gear ring 06 form a planetary reduction mechanism, further reducing the rotational speed and increasing the torque, and finally the power is output from the planet gear carrier 10 to the sealed transmission assembly.

[0084] In some alternative embodiments, the structural assembly diagram and disassembly diagram of the sealing assembly are as Figure 17 and Figure 18 shown, and it includes: a sealing main body and a transmission shaft 12 arranged in the sealing main body. A bearing is arranged between the transmission shaft and the sealing main body.

[0085] The sealing main body includes an outer cylinder 11 and a limit joint 16 connected in sequence. The outer cylinder is connected to the internal gear ring 06 in the reduction assembly. The limit joint 16 is provided with a transmission shaft hole and is in sealing cooperation with the transmission shaft through the transmission shaft hole.

[0086] The lower end of the transmission shaft 12 is provided with an output joint 18 to connect to the drill bit.

[0087] The bearing includes a thrust bearing 14 and a radial bearing 15.

[0088] In some alternative embodiments, the outer cylinder 11 is a stationary component of the sealed drive assembly. Its upper end is threadedly connected to the internal gear ring 06 of the reduction assembly, and its lower end is threadedly connected to the limit joint 16. The drive shaft 12 has a hollow structure and is installed inside the outer cylinder 11. The upper end is machined with internal teeth and a flow channel. A thrust bearing 14 and a set of radial bearings 15 are installed in the middle, separated by the shoulder in the middle and limited by the lower joint 16. The thrust bearing 14 and the radial ball bearings 15 ensure that when the outer cylinder 11 is stationary, the drive shaft 12 is allowed to rotate at high speed and limit its axial and radial directions. The upper and lower dynamic seals 13 and 17 enclose the two sets of bearings from the outside to prevent drilling fluid from flowing into the bearing group and affecting its normal operation. The lower end of the drive shaft 12 is threadedly connected to the output joint 18, and the output joint 18 is connected to the drill bit.

[0089] Based on the above composition structure, the working principle of the sealed drive assembly is as follows: The planet carrier 10 of the reduction assembly outputs torque to the drive shaft 12 through the meshing of internal and external gears. The bearings 14 and 15 achieve the static-dynamic separation of the drive shaft 12 and the outer cylinder 11. The drive shaft 12 transmits the torque to the drill bit through the output joint 18 to achieve rotary rock breaking. In addition, due to the action of the dynamic seals 13 and 17, the drilling fluid will not invade the bearing groups 14 and 15, but will enter its central hole after passing through the flow channel of the drive shaft 12, and then enter the output joint 18 and the drill bit nozzle in sequence to circulate and remove rock debris.

[0090] An axial flow vane type downhole motor provided in the second embodiment of the present invention is connected to the bottom of the drilling string, with a drill bit connected below, and is lowered to the bottom of the well for circulation and drilling. Plate vanes are placed in the rotor slots and extend under the action of springs to contact and fit with the inner wall of the stator, forming multiple relatively sealed spaces. The stator is an elliptical structure. When the drilling fluid enters the downhole motor through the drilling string, the drilling fluid passes through the diverter plate and enters the motor, acting on the plate vanes to form a force. Due to the elliptical structure of the stator, the extension distance of the plate vanes near the major axis is greater than that of the plate vanes near the minor axis, and the force formed by the drilling fluid on the plate vanes near the major axis is greater. This force drives the rotor to rotate around the axis, outputting rotational speed and torque, which is further output after passing through the reduction and transmission mechanisms to drive the drill bit to break rock. Specifically, the sun gear is driven to operate through the meshing of internal and external gears. After the torque is further amplified and the speed is reduced by the reduction assembly, it is transmitted to the sealed drive assembly to drive the drive shaft to operate, and the torque is transmitted to the drill bit through the output joint to break rock, ultimately converting the hydraulic energy of the drilling fluid into mechanical power output. Compared with the current downhole motors, it adopts a fully metal structure, has the characteristics of high temperature and high pressure resistance, and is suitable for various types of drilling fluids; it has a long service life, only the plate vanes are easily worn parts, and other parts usually do not break, with low use and maintenance costs, facilitating popularization and application; it has the characteristics of a compact structure, high temperature resistance, low-speed large torque output, and low production and maintenance costs.

[0091] Embodiment Three

[0092] Embodiment 3 of the present invention provides a method for using an axial flow vane type downhole motor, and its process is as Figure 19 shown, including the following steps:

[0093] S101: Install the axial flow vane type downhole motor at the bottom of the drilling string, and connect a drill bit to the bottom of the axial flow vane type downhole motor;

[0094] S102: Lower the axial flow vane type downhole motor to the bottom of the well. The drilling fluid enters the inside of the rotor through the input diverter disk in the drilling string and the motor assembly, driving the rotor to rotate; the rotational speed and torque output by the rotation of the rotor are transmitted to the transmission shaft in the seal assembly through the reduction assembly, and are output to the drill bit through the transmission shaft, driving the drill bit to rotate.

[0095] Optionally, the above method further includes that the drilling string rotates driven by a power source, driving the axial flow vane type downhole motor to rotate, and the drill bit rotates under the dual drive of the drilling string and the axial flow vane type downhole motor. After the drilling fluid drives the rotor to rotate, it flows out through the diverter disk, passes through the reduction assembly, the transmission shaft, and the output joint, and finally enters the drill bit to realize the function of circulating rock removal.

[0096] In some optional embodiments, the drilling fluid enters the inside of the rotor through the input diverter disk in the drilling string and the motor assembly, including:

[0097] 1) The drilling fluid in the drilling string enters the inside of the rotor through the diversion holes of the input diverter disk in the motor assembly;

[0098] 2) Under the action of the input diverter disk and the output diverter disk, the inner part of the rotor with multiple vanes is divided into two high-pressure chambers and two low-pressure chambers;

[0099] 3) Under the pressure difference between the high-pressure chamber and the low-pressure chamber, the vanes are pushed to rotate.

[0100] In some optional embodiments, under the pressure difference between the high-pressure chamber and the low-pressure chamber, pushing the vanes to rotate includes:

[0101] The drilling fluid enters the downhole motor through the drilling string. The drilling fluid enters the inside of the motor through the diverter disk 03. Since the vane 044 is placed in the groove of the rotor 04 and extends under the action of the spring 042, it contacts and fits with the inner wall of the stator 02. The drilling fluid acts on the vane 044. Due to the elliptical structure of the stator 02, the extension distance of the vane 044 near the major axis is greater than that of the vane 044 near the minor axis. The drilling fluid forms a greater acting force on the vane 044 near the major axis, and this acting force pushes the rotor 04 to rotate around the axis, outputting rotational speed and torque.

[0102] In some alternative embodiments, based on the above-mentioned output rotational speed and torque, the sun gear 08 is driven to operate through the meshing of internal and external gears. After the torque is further amplified and the rotational speed is reduced by the reduction assembly, it is transmitted to the sealed transmission assembly to drive the drive shaft 12 to operate. The torque is transmitted to the drill bit for rock breaking through the output joint 18, finally realizing the conversion of the hydraulic energy of the drilling fluid into mechanical power output. Based on the process of the method, after the drilling fluid drives the rotor 04 to rotate, it flows out through the flow dividing plate 05, passes through the reduction assembly, the drive shaft 12, and the output joint 18, and finally enters the drill bit to realize the function of circulating rock removal.

[0103] In some alternative embodiments, the axial flow vane type downhole motor has two working modes. One is the directional drilling mode, as shown in the above method. When the entire drill string is stationary and only the drilling fluid circulates, the drilling fluid flows through the downhole motor, and the motor outputs torque and rotational speed to drive the drill bit to operate. At this time, the entire pipe string and the outer shell of the downhole motor are stationary, and only the drill bit rotates to perform rock breaking, which can meet the drilling needs during directional drilling and build-up.

[0104] In some alternative embodiments, the axial flow vane type downhole motor has another working mode, the compound drilling mode. The drilling pipe string rotates driven by the power source, driving the axial flow vane type downhole motor to rotate, and the drill bit rotates driven by both the drilling pipe string and the axial flow vane type downhole motor.

[0105] In the compound drilling mode, when the entire drilling pipe string rotates, the downhole motor as a whole rotates with the drill string. On this basis, the drilling fluid drives the rotor 04 of the downhole motor to rotate, further outputting rotational speed and torque. The rotational speed generated by the downhole motor is superimposed on the original rotational speed of the drilling pipe string, allowing the drill bit to operate at a higher speed, improving the rock breaking efficiency and drilling speed.

[0106] A method for using an axial flow vane type downhole motor provided by the present invention solves the deficiencies existing in the current use of downhole motors. It has the following advantages:

[0107] 1. Adopting an all-metal structure, it has the characteristics of high temperature and high pressure resistance and is applicable to various types of drilling fluids.

[0108] 2. Directly doing work through hydraulic pressure, it has a large power density, a small volume, good build-up ability during drilling, and a small curvature radius.

[0109] 3. The working pressure drop increases with the increase of the resistance torque, and it has a strong overload capacity. The output rotational speed does not change with the load, and its technical characteristics are suitable for drilling.

[0110] 4. It has the characteristic of low-speed and high-torque output, and the reduction assembly can be selectively added to further reduce the volume and increase the output torque.

[0111] 5. All-metal structure, long service life. Only the plate wings are the vulnerable parts, and other components usually will not be damaged, with low use and maintenance costs, which is convenient for popularization and application.

[0112] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The appended method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy recited.

[0113] In the above detailed description, various features are combined in a single embodiment to simplify the present disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the present invention lies in a state less than all the features of the single disclosed embodiment. Accordingly, the appended claims are hereby expressly incorporated into the detailed description, where each claim stands on its own as a separate preferred embodiment of the present invention.

[0114] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but those of ordinary skill in the art should recognize that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, this term is covered in a manner similar to the term "including" as interpreted when "including" is used as a transitional word in a claim. In addition, any use of the term "or" in the specification or claims of the patent is intended to mean "non-exclusive or".

Claims

1. An axial flow vane type motor assembly, characterized in that, Comprising: The motor assembly includes an upper joint and a stator connected to each other, a rotor disposed in the elliptical inner hole of the stator, an input diverter disk and an output diverter disk respectively disposed at the upper and lower ends of the rotor; The rotor includes a rotor core shaft, and a plurality of spokes are provided on the rotor core shaft, and blade assemblies are provided in the grooves of each spoke; the blade assemblies include springs and blades, and the blades are connected to the inner wall of the elliptical inner hole under the action of the spring force; Two groups of diversion holes are provided on both the input diverter disk and the output diverter disk, and the diversion holes of the input diverter disk and the output diverter disk are staggered in position to guide the flow direction of the liquid in the rotor and realize driving the rotor to rotate.

2. The motor assembly according to claim 1, wherein, The number of spokes on the rotor core shaft is 8, and they are evenly arranged in a circumference.

3. The motor assembly according to claim 1, wherein The blade assembly further includes a sealing strip, which is installed in the sealing groove of the spoke; The sealing strip is made of a high-temperature resistant material; the blade is made of a soft metal material or the surface is electroplated with soft metal; the spring is a compression spring.

4. The motor assembly according to claim 1, wherein, Both the upper and lower ends of the stator are provided with bosses and external threads; positioning pins are provided on the bosses; the positioning pin on the upper boss cooperates with the positioning groove on the input diverter disk, and the positioning pin on the lower boss cooperates with the positioning groove on the output diverter disk.

5. The motor assembly according to any one of claims 1-4, characterized in that, A first gear output shaft is provided at the lower end of the rotor to output rotational speed and torque.

6. An axial flow vane type downhole motor, characterized in that, Comprising: A sealing assembly and the motor assembly according to any one of claims 1-5; The sealing assembly is connected to the motor assembly and is used to transmit rotational speed and torque to the drill bit through a transmission shaft.

7. The drill tool according to claim 6, wherein, A speed reduction assembly disposed between the motor assembly and the sealing assembly, the speed reduction assembly includes: an internal gear ring, a plurality of planetary gears, a planetary gear carrier and a sun gear; The internal gear ring is connected to the lower end of the stator, and its inner wall has teeth and meshes with the planetary gears; The sun gear is disposed among the plurality of planetary gears and meshes with each planetary gear respectively, and the sun gear is connected to the rotor in the motor assembly; The planetary gears are connected to the planetary gear carrier, and the planetary gear carrier is provided with a second gear output shaft to output rotational speed and torque.

8. The drill tool according to claim 6 or 7, characterized in that, The sealing assembly includes: a sealing body and a transmission shaft disposed in the sealing body, and a bearing is disposed between the transmission shaft and the sealing body; The sealing body includes an outer cylinder and a limit joint connected in sequence, the outer cylinder is connected to the internal gear ring in the speed reduction assembly, the limit joint is provided with a transmission shaft hole, and is hermetically fitted with the transmission shaft through the transmission shaft hole; An output joint is provided at the lower end of the transmission shaft to connect to the drill bit; The bearing includes a thrust bearing and a radial bearing.

9. Application of the axial flow blade type motor assembly according to any one of claims 1-5 and the axial flow blade type downhole motor drill according to any one of claims 6-8 in the drilling process.

10. A method for using the axial flow blade type downhole motor drill according to any one of claims 6-8, including: Install the axial flow blade type downhole motor drill at the bottom of the drilling string, and connect the drill bit to the bottom of the axial flow blade type downhole motor drill; Lower the axial flow vane type downhole motor to the bottom of the well. The drilling fluid enters the inside of the rotor through the input diverter disc in the drilling string and the motor assembly to drive the rotor to rotate. The rotational speed and torque output by the rotor are transmitted to the transmission shaft in the seal assembly through the reduction assembly, and are output to the drill bit through the transmission shaft to drive the drill bit to rotate.

11. The method according to claim 10, wherein The drilling fluid enters the inside of the rotor through the input diverter disc in the drilling string and the motor assembly to drive the rotor to rotate, including: The drilling fluid in the drilling string enters the inside of the rotor through the diversion holes of the input diverter disc in the motor assembly. Under the action of the input diverter disc and the output diverter disc, the inner part of the rotor with multiple vanes is divided into two high-pressure chambers and two low-pressure chambers. Under the pressure difference between the high-pressure chamber and the low-pressure chamber, the vanes are pushed to rotate.

12. The method according to claim 10 or 11, characterized in that, It further includes: The drilling string rotates driven by the power source, driving the axial flow vane type downhole motor to rotate, and the drill bit rotates under the double drive of the drilling string and the axial flow vane type downhole motor.

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