Downhole generator drive, downhole generator, multi-stage guide wheel and method of manufacture

Abstract

The application provides a downhole generator driving device, a downhole generator, a multistage guide wheel and a processing method of the multistage guide wheel. The downhole generator driving device comprises a multistage turbine, a multistage guide wheel, an isolation sheath and a supporting seat. The multistage guide wheel blades and the multistage turbine blades are staggered. The multistage guide wheel blades guide the drilling fluid to the multistage turbine blades, so that the drilling fluid can impact the multistage turbine blades and the output power of the multistage turbine blades is improved. The multistage turbine blades are integrated on a turbine shaft. The output power of the multistage turbine is the sum of the output powers of the multistage turbine blades, so that the multistage turbine can generate greater output power. The multistage turbine is arranged on a turbine shaft. The rotating speed of the multistage turbine is finally uniformly transmitted to the rotor shaft through the turbine shaft. The rotating speed of the turbine shaft is consistent, so that the structure for transmitting the rotating speed is not damaged, and the stability and reliability of the downhole generator are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil or gas drilling equipment, in particular to a downhole generator driving device, a downhole generator, a multi-stage guide wheel and a processing method of the multi-stage guide wheel. BACKGROUND

[0002] The downhole generator has the characteristics of long power supply time and large power output, and has been widely used as a power supply unit of a downhole drilling tool system. The downhole generator is placed in a drill string, and the high-speed flowing drilling fluid in the drill string impacts the turbine blades of the generator to make the turbine rotate. The turbine rotation drives the rotor shaft of the generator to rotate at the same speed. The rotor shaft of the generator is provided with a magnetic sheet, and an alternating magnetic field is formed when the rotor shaft rotates. The stator coil fixed in the generator cuts the magnetic lines of force to generate an induced electromotive force. After voltage stabilization and rectification, the downhole drilling tool system is provided with electric energy. In recent years, the downhole drilling tool system carries more and more measuring instruments, and the demand for electricity is increasing. For example, the rotary steering system provides power for the heavy load execution unit, and a large power turbine generator is needed to provide power support. For the turbine generator, whether it can output large power depends on the output power of the turbine. The output power of the turbine can be increased by adjusting the flow area or the blade angle of the turbine.

[0003] The maximum output power of a single-stage turbine is limited, and even full power output cannot meet the power demand of the system. Therefore, some people propose to use a multi-stage turbine driving structure to increase the output power of the turbine. For example, patent CN201010616378.6 proposes a "double-turbine downhole high-power generator". The upper turbine assembly and the lower turbine assembly are installed at both ends of the generator to achieve large power output. Since the upper and lower turbine assemblies lack guide wheel assemblies for turning and accelerating the fluid, the output power of the double-turbine downhole generator of this structure can only reach 500W, which is insufficient to maintain the normal operation of the rotary steering system with large power.

[0004] Based on the above-mentioned patent, patent CN201720377493.X proposes a "downhole multi-stage turbine generator" using a guide wheel assembly. The multi-stage turbine includes at least a first-stage turbine and a second-stage turbine, and the multi-stage turbine independently drives the generator rotor shaft. The first-stage turbine includes a first-stage guide flow stator and a first-stage turbine rotor, and the second-stage turbine includes a second-stage guide flow stator and a second-stage turbine rotor. Since the fluid flowing into the first-stage guide flow stator is axial, and the fluid flowing into the second-stage guide flow stator is from the previous stage turbine, it is difficult to achieve axial flow, so the rotation speeds of the first-stage turbine rotor and the second-stage turbine rotor are inconsistent. SUMMARY

[0005] The present application inventors find that the multi-stage turbine generator in the prior art has inconsistent rotational speeds of the first-stage turbine rotor and the second-stage turbine rotor, and when driving the same generator rotor shaft, the rotational speed transmitted has a difference, which easily damages the magnetic coupling mechanism for transmitting the rotational speed, and the stability and reliability of the device are low, and it is difficult to realize large-scale application.

[0006] In view of the above problems, it is necessary to propose an underground generator driving device to solve or partially solve the above problems, and the technical scheme of the present application is as follows:

[0007] In a first aspect, the present application proposes an underground generator driving device for driving a generator rotor shaft to rotate, comprising a multi-stage turbine, a multi-stage guide wheel, an isolation sheath and a support seat, wherein:

[0008] The isolation sheath is connected with the support seat, and the support seat comprises a rotor shaft hole so that the rotor shaft passes through the hole with a gap and extends into the isolation sheath;

[0009] The multi-stage turbine comprises a turbine shaft and multi-stage turbine blades arranged on the turbine shaft, the turbine shaft is a hollow shaft, the turbine shaft is rotatably connected with the isolation sheath, and the turbine shaft can drive the generator rotor shaft to rotate;

[0010] The multi-stage guide wheel comprises a guide wheel base and multi-stage guide wheel blades connected with the guide wheel base, the guide wheel base is fixedly connected with the isolation sheath, the number of stages of the multi-stage guide wheel blades is the same as that of the multi-stage turbine blades, and the multi-stage guide wheel blades and the multi-stage turbine blades are staggered; the multi-stage guide wheel blades are used for guiding the drilling fluid to the multi-stage turbine blades, and the multi-stage turbine blades drive the turbine shaft to rotate under the impact of the drilling fluid, so that the turbine shaft drives the generator rotor shaft to rotate.

[0011] Further, first and second coupling magnetic sheets are further included, and the isolation sheath is arranged between the first and second coupling magnetic sheets;

[0012] The first coupling magnetic sheet is arranged on the inner wall of the turbine shaft, and the second coupling magnetic sheet is arranged on the circumferential edge of the rotor shaft, and the second coupling magnetic sheet is magnetically coupled with the first coupling magnetic sheet.

[0013] Further, the multi-stage turbine blades at least comprise first and second turbine blades;

[0014] The multi-stage guide wheel blades at least comprise first and second guide wheel blades, the first turbine blade is arranged between the first and second guide wheel blades, and the second guide wheel blade is located between the first and second turbine blades.

[0015] Further, the guide wheel base comprises a guide wheel shell and a first guide wheel shaft, the guide wheel shell is connected with the first guide wheel blade and the second guide wheel blade respectively, the first guide wheel blade is arranged on the first guide wheel shaft, and the first guide wheel shaft is connected with the isolation sheath.

[0016] Further, the multi-stage guide wheel comprises a first unit and a second unit, and the first unit and the second unit can be assembled into the complete multi-stage guide wheel.

[0017] The driving device further comprises a snap ring and a positioning nut, the snap ring is sleeved on the isolation sheath, and the end face of the snap ring is provided with a convex annular ring; the positioning nut is sleeved on the first guide wheel shaft and is in threaded connection with the isolation sheath.

[0018] The inner wall of the first guide wheel shaft is provided with a clamping groove matched with the convex annular ring.

[0019] The first unit and the second unit are sleeved on the isolation sheath, the positioning nut pushes the first guide wheel shaft towards the direction of the snap ring, and the convex annular ring is inserted into the clamping groove.

[0020] Further, the downhole generator driving device further comprises two flat keys, the first guide wheel shaft is provided with two first key grooves, the isolation sheath is provided with second key grooves corresponding to the first key grooves, and the flat keys are matched with the first key grooves and the second key grooves respectively.

[0021] Further, one end of the positioning nut away from the isolation sheath is a tapered surface, and the tapered surface is perpendicular to the working surface of the first guide wheel blade.

[0022] Further, the downhole generator driving device further comprises a first sliding bearing and a second sliding bearing, the first sliding bearing comprises a first sliding bearing outer ring and a first sliding bearing inner ring connected with each other, and the second sliding bearing comprises a second sliding bearing outer ring and a second sliding bearing inner ring connected with each other.

[0023] The first sliding bearing outer ring and the second sliding bearing outer ring are respectively mounted at two ends of the inner wall of the turbine shaft, the first sliding bearing inner ring is mounted on the isolation sheath corresponding to the first sliding bearing outer ring, and the second sliding bearing inner ring is mounted on the support base corresponding to the second sliding bearing outer ring.

[0024] In a second aspect, the present application provides a downhole generator, characterized in that comprising a generator body and the downhole generator driving device.

[0025] The generator body comprises a generator rotor shaft and a generator shell, the generator rotor shaft is rotatably connected with the generator shell, and the support base is fixed to the generator shell.

[0026] In a third aspect, the application provides a multi-stage guide wheel for the downhole generator driving device, comprising a guide wheel base and a multi-stage guide wheel blade connected to the guide wheel base.

[0027] In the state that the multi-stage guide wheel is installed in the downhole generator driving device, the guide wheel base is fixedly connected to the isolation sheath, and the multi-stage guide wheel blade is staggered with the multi-stage turbine blade.

[0028] In a fourth aspect, the application provides a processing method of the multi-stage guide wheel, comprising:

[0029] The processed first guide wheel and second guide wheel are sleeved on a supporting mandrel, and the first guide wheel and the second guide wheel are aligned, wherein the second guide wheel comprises a second guide wheel base and a second guide wheel blade.

[0030] The limiting baffle is sleeved on the supporting mandrel, and the lock nut is screwed into the supporting mandrel.

[0031] After the limiting baffle is aligned with the first guide wheel, the lock nut is tightened, and the limiting baffle is pushed into the protective sleeve as a whole until the limiting baffle abuts against the end face of the protective sleeve.

[0032] The protective sleeve is rotated until the protective sleeve is aligned with the limiting baffle.

[0033] After the blades of the first guide wheel and the second guide wheel blade are preliminarily fixed to the protective sleeve by using a gluing or welding process, the lock nut is unscrewed, and the limiting baffle and the supporting mandrel are removed, thereby obtaining a guide wheel semi-finished product.

[0034] The guide wheel semi-finished product is cut into two halves along an axis, the blades of the first guide wheel and the second guide wheel blade are spot-welded to the protective sleeve for reinforcement, and finally the second guide wheel base is removed, thereby obtaining the multi-stage guide wheel.

[0035] Based on the above technical solution, the application has the following beneficial effects compared with the prior art:

[0036] The application discloses a downhole generator driving device, wherein the multi-stage guide wheel blade is staggered with the multi-stage turbine blade, the multi-stage guide wheel blade guides the drilling fluid to the multi-stage turbine blade, the drilling fluid can impact the multi-stage turbine blade at a high speed, the output power of the multi-stage turbine blade is improved, the multi-stage turbine blade is integrated on a turbine shaft, the output power of the multi-stage turbine is the sum of the output power of the multi-stage turbine blade, the multi-stage turbine can generate greater output power, the rotating speed of the multi-stage turbine blade is finally uniformly transmitted to the generator rotor shaft through the turbine shaft, the rotating speed of the turbine shaft is consistent, and therefore the structure for transmitting the rotating speed is not damaged, and the stability and reliability of the downhole generator can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a schematic diagram of the structure of a downhole generator driving device in an embodiment of the present application;

[0038] Figure 2 is a schematic diagram of the structure of a downhole generator in an embodiment of the present application;

[0039] Figure 3 is a schematic diagram of the structure of another downhole generator in an embodiment of the present application;

[0040] Figure 4 is a schematic diagram of the structure of a multi-stage guide wheel in an embodiment of the present application;

[0041] Figure 5 is a schematic diagram of the flow of a processing method for a multi-stage guide wheel in an embodiment of the present application;

[0042] Figure 6 is a schematic diagram of the structure of a device used in a processing method for a multi-stage guide wheel in an embodiment of the present application.

[0043] Figure 1 The reference numerals in the figure are as follows: 1 - multi-stage guide wheel, 1a - first guide wheel blade, 1b - second guide wheel blade, 2 - multi-stage turbine, 2a - first turbine blade, 2b - second turbine blade, 2c - turbine shaft, 3 - positioning nut, 4 - generator rotor shaft, 9 - first coupling magnetic sheet, 10 - second coupling magnetic sheet, 11 - adjustment sheath, 12 - second sliding bearing outer ring, 13 - second sliding bearing inner ring, 14 - support seat, 15 - isolation sheath, 16 - first sliding bearing outer ring, 17 - first sliding bearing inner ring, 18 - snap ring, 19 - flat key.

[0044] Figure 2 The reference numerals in the figure are as follows: 1 - multi-stage guide wheel, 2 - multi-stage turbine, 3 - positioning nut, 4 - generator rotor shaft, 5 - stator coil, 6 - rotor magnet, 7 - rotary guide system, 8 - formation.

[0045] Figure 3 The reference numerals in the figure are as follows: 1 - multi-stage guide wheel, 1a - first guide wheel blade, 1b - second guide wheel blade, 2 - multi-stage turbine, 2a - first turbine blade, 2b - second turbine blade, 3 - positioning nut, 4 - generator rotor shaft, 5 - stator coil, 6 - rotor magnet, 9 - first coupling magnetic sheet, 10 - second coupling magnetic sheet, 11 - adjustment sheath, 12 - second sliding bearing outer ring, 13 - second sliding bearing inner ring 13, 14 - support seat, 15 - isolation sheath, 16 - first sliding bearing outer ring, 17 - first sliding bearing inner ring, 18 - snap ring, 19 - flat key, 20 - generator housing, 21 - first rolling bearing, 22 - second rolling bearing.

[0046] Figure 4The reference signs in the figure are respectively: 1a-first guide vane, 1b-second guide vane, 1c-guide housing, 1d-first guide shaft.

[0047] Figure 6 The reference signs in the figure are respectively: 1_1-first guide wheel, 1_2-second guide wheel, 1_3-protection sleeve, 20-supporting mandrel, 21-limiting baffle, 22-lock nut; ①-third positioning mark, ②-first positioning mark, ③-fourth positioning mark, ④-second positioning mark. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0049] Example one

[0050] The present embodiment proposes a downhole generator driving device for driving a generator rotor shaft 4 to rotate, as shown in the figure, comprising a multi-stage turbine 2, a multi-stage guide wheel 1, an isolation sleeve 15 and a supporting seat 14, wherein: Figure 1

[0051] The isolation sleeve 15 is connected with the supporting seat 14, and the supporting seat 14 comprises a rotor shaft hole so that the rotor shaft passes through with clearance and extends into the isolation sleeve 15;

[0052] The multi-stage turbine 2 comprises a turbine shaft 2c and a plurality of multi-stage turbine vanes arranged on the turbine shaft 2c, the turbine shaft 2c is a hollow shaft, the turbine shaft 2c is rotatably connected with the isolation sleeve 15, and the turbine shaft 2c can drive the generator rotor shaft 4 to rotate;

[0053] The multi-stage guide wheel 1 comprises a guide wheel base and a plurality of multi-stage guide vanes connected with the guide wheel base, the guide wheel base is fixedly connected with the isolation sleeve 15, the number of stages of the multi-stage guide vanes is the same as that of the multi-stage turbine vanes, and the multi-stage guide vanes and the multi-stage turbine vanes are staggered; the multi-stage guide vanes are used for guiding the drilling fluid to the multi-stage turbine vanes, the multi-stage turbine vanes drive the turbine shaft 2c to rotate under the impact of the drilling fluid, so that the turbine shaft 2c drives the generator rotor shaft 4 to rotate.

[0054] ​In the working state of the driving device in the embodiment, the support seat 14 is fixed, the generator rotor shaft 4 passes through the support seat 14 and extends into the isolation sheath 15, and a preset gap is reserved between the isolation sheath 15 and the support seat 14; the generator rotor shaft 4 can rotate relative to the isolation sheath 15; the drilling fluid impacts the multi-stage turbine blades after being guided by the multi-stage guide vane, and the multi-stage turbine blades drive the turbine shaft 2c to rotate under the impact of the drilling fluid, and the turbine shaft 2c drives the generator rotor shaft 4 to rotate.

[0055] The multi-stage guide vane can accelerate the impact of the drilling fluid on the multi-stage turbine blade, and the output power of the multi-stage turbine 2 is increased; the turbine shaft 2c is integrated with the multi-stage turbine blade, and the output power of the multi-stage turbine 2 is the sum of the output powers of the multi-stage turbine blades, so that the multi-stage turbine 2 can generate greater output power; in actual use, the output power of the multi-stage turbine 2 can reach 1500W; when the rotary steering system 7 encounters heavy load or variable load, the multi-stage turbine 2 with large power has strong bearing capacity and small output speed change, can reduce the difference of the output voltage of the downhole generator, and effectively improves the stability of the electrical system of the rotary steering system 7.

[0056] The multi-stage guide vane and the multi-stage turbine blade are staggered, the multi-stage guide vane guides the drilling fluid to the multi-stage turbine blade, the impact of the drilling fluid on the multi-stage turbine blade can be accelerated, and the output power of the multi-stage turbine blade is increased; the turbine shaft 2c is integrated with the multi-stage turbine blade, and the output power of the multi-stage turbine 2 is the sum of the output powers of the multi-stage turbine blades, so that the multi-stage turbine 2 can generate greater output power; the rotation speed of the multi-stage turbine blade is ultimately uniformly transmitted to the generator rotor shaft 4 through the turbine shaft 2c, the rotation speed of the turbine shaft 2c is consistent, so that the structure for transmitting the rotation speed is not damaged, and the stability and reliability of the downhole generator can be improved.

[0057] In one embodiment, the downhole generator further comprises a first coupling magnetic sheet 9 and a second coupling magnetic sheet 10, and the isolation sheath 15 is arranged between the first coupling magnetic sheet 9 and the second coupling magnetic sheet 10.

[0058] The first coupling magnetic sheet 9 is arranged on the inner wall of the turbine shaft 2c, and the second coupling magnetic sheet 10 is arranged on the circumferential edge of the rotor shaft, and the second coupling magnetic sheet 10 is magnetically coupled with the first coupling magnetic sheet 9.

[0059] In this embodiment, a first coupling magnetic sheet 9 is installed on the inner wall of the turbine shaft 2c, and the first coupling magnetic sheet 9 is fixedly connected with the turbine shaft 2c. Correspondingly, a second coupling magnetic sheet 10 is installed on the surface of the rotor shaft, and the second coupling magnetic sheet 10 is fixedly connected with the rotor shaft. The first coupling magnetic sheet 9 and the second coupling magnetic sheet 10 are both circular ring-shaped magnetic column bodies formed by combining fan ring sections with magnetism. The first coupling magnetic sheet 9 and the second coupling magnetic sheet 10 non-contactingly transmit the output rotating speed and the output torque of the turbine shaft 2c to the rotor shaft through magnetic coupling, thereby avoiding the abrasion and noise caused by contact transmission and making the rotating speed of the rotor shaft consistent with the rotating speed of the turbine shaft 2c. The isolation sheath 15 can prevent the drilling fluid from invading the inside of the generator and can also realize the magnetic conduction effect.

[0060] In one embodiment, as shown in Figure 1 and Figure 4 , the multi-stage turbine blades at least include a first turbine blade 2a and a second turbine blade 2b; the multi-stage guide wheel blades at least include a first guide wheel blade 1a and a second guide wheel blade 1b, the first turbine blade 2a is arranged between the first guide wheel blade 1a and the second guide wheel blade 1b, and the second guide wheel blade 1b is located between the first turbine blade 2a and the second turbine blade 2b.

[0061] In this embodiment, taking two-stage turbine blades and two-stage guide wheel blades as an example, the first guide wheel blade 1a is arranged at the front end of the first turbine blade 2a, the first turbine blade 2a is arranged between the first guide wheel blade 1a and the second guide wheel blade 1b, and the second guide wheel blade 1b is located between the first turbine blade 2a and the second turbine blade 2b. The case of three-stage turbine blades and more-stage turbine blades can be referred to the case of two-stage turbine blades, and it is ensured that one-stage guide wheel blade is arranged in front of each turbine blade. The drilling fluid is accelerated to impact the multi-stage turbine blades through the multi-stage guide wheel blades, so that the output power of the multi-stage turbine 2 can be improved.

[0062] In one embodiment, as shown in Figure 4 , the guide wheel body includes a guide wheel shell 1c and a first guide wheel shaft 1d, the guide wheel shell 1c is connected with the first guide wheel blade 1a and the second guide wheel blade 1b respectively, the first guide wheel blade 1a is arranged on the first guide wheel shaft 1d, and the first guide wheel shaft 1d is connected with the isolation sheath 15. Through the connection of the guide wheel shell 1c with the first guide wheel blade 1a and the second guide wheel blade 1b respectively, the first guide wheel blade 1a is arranged on the first guide wheel shaft 1d, and the inside of the second guide wheel blade 1b is empty. Only by connecting the first guide wheel shaft 1d with the isolation sheath 15, the installation of the multi-stage guide wheel 1 can be realized, which is convenient and fast.

[0063] In one embodiment, the multi-stage guide wheel 1 comprises a first unit and a second unit, which can be assembled into a complete multi-stage guide wheel 1; as Figure 1 As shown, the driving device further comprises a snap ring 18 and a positioning nut 3, the snap ring 18 is sleeved on the isolation sheath 15, and the end face of the snap ring 18 is provided with a protruding ring; the positioning nut 3 is sleeved on the first guide wheel shaft 1d and is in threaded connection with the isolation sheath 15; the inner wall of the first guide wheel shaft 1d is provided with a clamping groove matched with the protruding ring; the first unit and the second unit are sleeved on the isolation sheath 15, and the positioning nut 3 pushes the first guide wheel shaft 1d towards the direction of the snap ring 18 until the protruding ring is inserted into the clamping groove.

[0064] In this embodiment, the first unit comprises one half of the first guide wheel blade 1a, one half of the second guide wheel blade 1b, one half of the guide wheel shell 1c and one half of the first guide wheel shaft 1d; the first unit comprises the other half of the first guide wheel blade 1a, the other half of the second guide wheel blade 1b, the other half of the guide wheel shell 1c and the other half of the first guide wheel shaft 1d.

[0065] In a further embodiment, the downhole generator driving device further comprises two flat keys 19, the first guide wheel shaft 1d is provided with two first key grooves, the isolation sheath 15 is provided with second key grooves corresponding to the first key grooves, and the flat keys 19 are matched with the first key grooves and the second key grooves respectively.

[0066] In this embodiment, after the multi-stage turbine 2 is installed, the first unit and the second unit are sleeved on the isolation sheath 15, the snap ring 18 is sleeved on the isolation sheath 15, the flat keys 19 are placed in the second key grooves of the isolation sheath 15, and the first guide wheel shaft 1d divided into two parts is designed with a first key groove on each part, so that the first key groove is matched with the flat key 19, then the first unit and the second unit are combined into a whole multi-stage guide wheel 1 and are tightly held by the snap ring 18 to prevent separation, and finally the positioning nut 3 is tightened to fix the whole driving device.

[0067] In one embodiment, the end of the positioning nut 3 away from the isolation sheath 15 is a tapered surface, and the tapered surface is perpendicular to the working surface of the first guide wheel blade 1a. By setting the end of the positioning nut 3 away from the isolation sheath 15 as a tapered surface, the tapered surface is perpendicular to the working surface of the guide wheel blade, the drilling fluid is divided into an annular cross section, the annular cross section is consistent with the working surface of the first guide wheel blade 1a, the drilling fluid vertically impacts the working surface of the first guide wheel blade 1a, and the force of the drilling fluid on the guide wheel and the turbine is maximized to improve the utilization rate of the drilling fluid.

[0068] In one embodiment, the downhole generator drive device also includes a first sliding bearing and a second sliding bearing, the first sliding bearing includes a first sliding bearing outer ring 16 and a first sliding bearing inner ring 17 connected to each other, and the second sliding bearing includes a second sliding bearing outer ring 12 and a second sliding bearing inner ring 13 connected to each other; the first sliding bearing outer ring 16 and the second sliding bearing outer ring 12 are respectively installed at both ends of the inner wall of the turbine shaft 2c, the first sliding bearing inner ring 17 is installed on the isolation sleeve 15 corresponding to the first sliding bearing outer ring 16, and the second sliding bearing inner ring 13 is installed on the support seat 14 corresponding to the second sliding bearing outer ring 12.

[0069] In this embodiment, the turbine shaft 2c is supported by a first and second sliding bearings, allowing it to rotate relative to the isolation sleeve 15. The use of sliding bearings facilitates reliable bearing operation under high-vibration drilling conditions. Furthermore, the continuous flow of drilling fluid eliminates the lubrication challenges associated with the sliding bearings. A hardened wear-resistant layer is sintered on the inner and outer contact surfaces of the first and second sliding bearings. This layer increases the lifespan of the sliding bearings and reduces frictional resistance between the bearings. In actual use, an adjustment sleeve 11 can be positioned between the second sliding bearing outer ring 12 and the first coupling magnetic plate 9 to adjust and limit the axial direction of the second sliding bearing outer ring 12.

[0070] Example 2

[0071] In this embodiment, Figure 2 As shown, the function of the downhole generator is to supply power to the measurement and transmission module and the motor module of the rotary steering system 7. In the rotary steering system 7, the measurement and transmission module mainly includes the measurement and control circuit and the sensor. The power consumption of these two parts is relatively small and stable, and can be regarded as a constant small load, which has almost no effect on the output of the generator; while the power consumption of the motor module comes from the guidance execution unit. The guidance execution unit contacts the formation 8 under the drive of the motor module. The hardness of the drilled formation 8 and the drill string pressure borne by the drill bit are applied to the guidance execution unit as a load, and then fed back to the motor by the guidance execution unit, which ultimately affects the output of the downhole generator in the form of an electrical load. This part of the load is heavy and changes frequently, and has high requirements on the load performance of the downhole generator. The downhole generator turbine drive structure with multiple sets of blades can improve the load capacity of the generator and reduce the difference in output voltage values, which is very necessary for improving the electrical control stability of the rotary steering system 7.

[0072] The embodiment of the present invention proposes a downhole generator, combined with Figures 1-3 As shown, it includes a generator body and the downhole generator driving device described in embodiment 1;

[0073] The generator body comprises a generator rotor shaft 4 and a generator housing 20, the generator rotor shaft 4 is rotatably connected with the generator housing 20, and the support seat 14 is fixed to the generator housing 20.

[0074] The downhole generator provided in the embodiment of the present application is characterized in that the multi-stage guide vane and the multi-stage turbine vane are staggered, the multi-stage guide vane guides the drilling fluid to the multi-stage turbine vane, the drilling fluid can impact the multi-stage turbine vane at a high speed, the output power of the multi-stage turbine vane is increased, the multi-stage turbine 2 is integrated with the multi-stage turbine vane on the turbine shaft 2c, the output power of the multi-stage turbine 2 is the sum of the output power of the multi-stage turbine vane, the multi-stage turbine 2 can generate greater output power, the multi-stage turbine vane is arranged on the turbine shaft 2c, the rotating speed of the multi-stage turbine vane is finally uniformly transmitted to the generator rotor shaft 4 through the turbine shaft 2c, the rotating speed of the turbine shaft 2c is consistent, therefore, the structure for transmitting the rotating speed is not damaged, and the stability and reliability of the downhole generator are improved.

[0075] In one embodiment, the downhole generator further comprises a first rolling bearing 21 and a second rolling bearing 22, the first rolling bearing 21 is arranged on the support seat 14, the second rolling bearing 22 is arranged on the generator housing 20, and the generator rotor shaft 4 penetrates through the first rolling bearing 21 and the second rolling bearing 22. The generator rotor shaft 4 is supported by the first rolling bearing 21 and the second rolling bearing 22, so that the generator rotor shaft 4 can rotate relative to the support seat 14.

[0076] In one embodiment, the generator rotor shaft 4 is provided with rotor magnets 6 with N and S poles alternately arranged at one end in the generator housing 20, and the inner wall of the generator housing 20 is provided with stator coils 5 corresponding to the positions of the rotor magnets 6.

[0077] In the embodiment, the generator rotor shaft 4 is provided with rotor magnets 6 with N and S poles alternately arranged at one end in the generator housing 20, the inner wall of the support seat 14 is provided with stator coils 5 corresponding to the positions of the rotor magnets 6, when the generator rotor shaft 4 rotates, a magnetic field is formed around the generator rotor shaft 4, the stator coils 5 fixed to the inner wall of the support seat 14 continuously cut the magnetic lines, an induced electromotive force is generated, and the induced electromotive force supplies power to the measurement module and the motor module of the rotary guide system 7 after being stabilized and rectified.

[0078] The working principle of the downhole generator in the embodiment is as follows: the flow sequence of the drilling fluid is the first guide wheel blade 1a, the first turbine blade 2a, the second guide wheel blade 1b and the second turbine blade 2b, the first guide wheel blade 1a and the second guide wheel blade 1b do not rotate, and play a guiding and accelerating role on the drilling fluid, when the drilling fluid impacts the multi-stage turbine 2, the first turbine blade 2a and the second turbine blade 2b are powered, the first coupling magnetic sheet 9 inside the turbine shaft 2c and the second coupling magnetic sheet 10 on the surface of the rotor shaft are used to transmit the output rotating speed and output torque of the turbine to the rotor shaft in a magnetic coupling mode, drive the generator rotor shaft 4 to rotate at the same speed as the turbine shaft 2c, and in the generator, the surface of the generator rotor shaft 4 is arranged with N and S pole alternating rotor magnets 6, when the rotor shaft rotates, a magnetic field is formed around it, the stator coil 5 fixed to the support seat 14 continuously cuts the magnetic lines, and an induced electromotive force is generated, which is used to supply power to the measurement and transmission module and the motor module of the rotary steering system 7 after voltage stabilization and rectification.

[0079] Embodiment three

[0080] The embodiment of the present application proposes a multi-stage guide wheel for the downhole generator driving device described in embodiment one, as shown in the figure, comprising a guide wheel base and a plurality of guide wheel blades connected with the guide wheel base. Figure 4

[0081] In the state that the multi-stage guide wheel is installed in the downhole generator driving device, the guide wheel base is fixedly connected with the isolation sheath 15, and the plurality of guide wheel blades are staggered with the plurality of turbine blades.

[0082] The multi-stage guide wheel proposed in the embodiment of the present application can make the drilling fluid impact the plurality of turbine blades at high speed, improve the output power of the multi-stage turbine, and thus improve the output power of the downhole generator driving device.

[0083] In one specific embodiment, the plurality of guide wheel blades at least comprise a first guide wheel blade 1a and a second guide wheel blade 1b; the guide wheel base comprises a guide wheel shell 1c and a first guide wheel shaft 1d, the guide wheel shell 1c is connected with the first guide wheel blade 1a and the second guide wheel blade 1b respectively, and the first guide wheel blade 1a is arranged on the first guide wheel shaft 1d.

[0084] In the embodiment, the guide wheel shell 1c is connected with the first guide wheel blade 1a and the second guide wheel blade 1b respectively, the first guide wheel blade 1a is arranged on the first guide wheel shaft 1d, and the inside of the second guide wheel blade 1b is empty, so that the multi-stage guide wheel can be installed only by connecting the first guide wheel shaft 1d with the isolation sheath 15 of the driving device, which is convenient and fast.

[0085] Embodiment four

[0086] ​This embodiment proposes a method for processing the multi-stage guide wheel described in the third embodiment. Figure 5 As shown, including:

[0087] Step S11: Mounting the processed first guide wheel and the second guide wheel on the supporting core shaft, aligning the first guide wheel and the second guide wheel, wherein the second guide wheel includes a second guide wheel base and a second guide wheel blade;

[0088] Step S12: Fit the limit stopper onto the support core shaft, and screw the lock nut into the support core shaft;

[0089] Step S13: After aligning the limit block with the first guide wheel, tighten the lock nut and push the entire nut into the protective sleeve until the limit block abuts against the end surface of the protective sleeve;

[0090] Step S14: rotating the protective sleeve until the protective sleeve is aligned with the limiting block;

[0091] Step S15: After preliminarily fixing the blades of the first guide wheel and the blades of the second guide wheel to the protective sleeve by gluing or welding, unscrew the lock nut, remove the limit block and the supporting core shaft, and obtain the semi-finished guide wheel;

[0092] Step S16: Cut the semi-finished guide wheel into two halves along the axis, then spot-weld and reinforce the blades of the first guide wheel and the second guide wheel blades with the protective sleeve, and finally remove the second guide wheel base to obtain a multi-stage guide wheel.

[0093] The above method applied Figure 6 The processing device shown, such as Figure 6 As shown, 1_1-first guide wheel, 1_2-second guide wheel, 1_3-protective sleeve, 20-support core shaft, 21-limit block, 22-lock nut; ①-third positioning mark, ②-first positioning mark, ③-fourth positioning mark, ④-second positioning mark.

[0094] Applied Figure 6 The processing device shown finally obtains Figure 4 The multi-stage guide wheel shown, Figure 4 The reference numerals in the figures are: 1a-first guide wheel blade, 1b-second guide wheel blade, 1c-guide wheel housing, 1d-first guide wheel shaft.

[0095] The processing method of the guide wheel provided in this embodiment can produce two halves of the guide wheel, which are then mounted on the turbine to form a combination of the guide wheel and the turbine. The combination serves as a core component of the downhole generator turbine drive structure and is an execution unit in the downhole generator turbine drive structure that converts the internal energy of the drilling fluid into the kinetic energy of the generator rotor shaft, providing strong protection for the multi-stage guide wheel in Example 1.

[0096] In step S11, aligning the first guide wheel and the second guide wheel includes: making a first positioning mark on the first guide wheel, making a second positioning mark on the second guide wheel, and aligning the first positioning mark with the second positioning mark.

[0097] In step S13, aligning the limit block with the first guide wheel includes: making a third limit mark on the limit block, and aligning the third limit mark with the first positioning mark.

[0098] In step S14, aligning the protective sleeve with the limiting block includes: making a fourth positioning mark on the protective sleeve, and aligning the fourth limiting mark with the third limiting mark.

[0099] In the foregoing detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that 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 invention comprises less than all the features of any individual disclosed embodiment. The appended claims are therefore hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0100] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purposes of describing the above embodiments, but one of ordinary skill in the art will recognize that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including," as explained in terms of "including," used as a transitional word in the claims. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or."

Claims

1. A downhole generator driving device for driving the generator rotor shaft to rotate, characterized in that: It includes a multi-stage turbine, a multi-stage guide wheel, an isolation sleeve and a support seat, wherein: The isolation sleeve is connected to the support base, and the support base includes a rotor shaft hole so that the rotor shaft can pass through with clearance and extend into the isolation sleeve; The multi-stage turbine includes a turbine shaft and multi-stage turbine blades arranged on the turbine shaft. The turbine shaft is a hollow shaft, rotatably connected to the isolation sleeve, and can drive the generator rotor shaft to rotate; The multi-stage guide wheel includes a guide wheel base and multi-stage guide wheel blades connected to the guide wheel base, the guide wheel base is fixedly connected to the isolation sleeve, the number of stages of the multi-stage guide wheel blades is the same as the number of stages of the multi-stage turbine blades, and the multi-stage guide wheel blades and the multi-stage turbine blades are staggered; the multi-stage guide wheel blades are used to guide drilling fluid to the multi-stage turbine blades, and the multi-stage turbine blades drive the turbine shaft to rotate under the impact of the drilling fluid, so that the turbine shaft drives the generator rotor shaft to rotate; The guide wheel base includes a guide wheel housing and a first guide wheel shaft, the guide wheel housing is connected to the first guide wheel blade and the second guide wheel blade respectively, the first guide wheel blade is arranged on the first guide wheel shaft, and the first guide wheel shaft is connected to the isolation sleeve; The multi-stage guide wheel includes a first unit and a second unit, and the first unit and the second unit can be assembled into the complete multi-stage guide wheel; The driving device further includes a snap ring and a positioning nut. The snap ring is sleeved on the isolation sleeve, and a raised ring is provided on the end face of the snap ring. The positioning nut is sleeved on the first guide wheel shaft and is threadedly connected to the isolation sleeve. The inner wall of the first guide wheel shaft is provided with a groove matching the raised ring; The first unit and the second unit are sleeved on the isolation sleeve, and the positioning nut pushes the first guide wheel axis toward the clamping ring until the raised ring is inserted into the clamping groove; One end of the positioning nut away from the isolation sleeve is a conical surface, and the conical surface is perpendicular to the working surface of the first guide wheel blade.

2. The downhole generator driving device according to claim 1, characterized in that: It also includes a first coupling magnetic sheet and a second coupling magnetic sheet, wherein the isolation sheath is disposed between the first coupling magnetic sheet and the second coupling magnetic sheet; The first coupling magnetic piece is arranged on the inner wall of the turbine shaft; the second coupling magnetic piece is arranged on the circumference of the generator rotor shaft, and the second coupling magnetic piece is magnetically coupled to the first coupling magnetic piece.

3. The downhole generator driving device according to claim 2, characterized in that: The multi-stage turbine blades include at least a first turbine blade and a second turbine blade; The multi-stage stator blades include at least a first stator blade and a second stator blade. The first turbine blade is disposed between the first stator blade and the second stator blade. The second stator blade is located between the first turbine blade and the second turbine blade.

4. The downhole generator driving device according to claim 1, characterized in that: It also includes two flat keys. The first guide wheel shaft is provided with two first key slots. The isolation sleeve is provided with second key slots corresponding to the first key slots. The flat keys are matched with the first key slots and the second key slots respectively.

5. The downhole generator driving device according to claim 1, characterized in that: Also included are a first sliding bearing and a second sliding bearing, wherein the first sliding bearing comprises a first sliding bearing outer ring and a first sliding bearing inner ring connected to each other, and the second sliding bearing comprises a second sliding bearing outer ring and a second sliding bearing inner ring connected to each other; A first sliding bearing outer ring and a second sliding bearing outer ring are respectively installed at both ends of the inner wall of the turbine shaft, a first sliding bearing inner ring is installed on the isolation sleeve corresponding to the first sliding bearing outer ring, and a second sliding bearing inner ring is installed on the support seat corresponding to the second sliding bearing outer ring.

6. A downhole generator, characterized in that: It comprises a generator body and the downhole generator driving device according to any one of claims 1 to 5; The generator body includes a generator rotor shaft and a generator housing. The generator rotor shaft is rotatably connected to the generator housing, and the support base is fixed to the generator housing.

7. The downhole generator according to claim 6, characterized in that: It also includes a first rolling bearing and a second rolling bearing, wherein the first rolling bearing is arranged on the support seat, the second rolling bearing is arranged on the generator housing, and the generator rotor shaft passes through the first rolling bearing and the second rolling bearing.

8. The downhole generator according to claim 7, characterized in that: A rotor magnet with alternating N and S poles is provided at one end of the generator rotor shaft located in the generator housing, and a stator coil is provided on the inner wall of the generator housing at a position corresponding to the rotor magnet.

9. A multi-stage guide wheel, used for the downhole generator drive device according to any one of claims 1 to 5, characterized in that: It includes a guide wheel base and multi-stage guide wheel blades connected to the guide wheel base; The multi-stage guide wheel is installed in the downhole generator drive device, the guide wheel base is fixedly connected to the isolation sleeve, and the multi-stage guide wheel blades are staggered with the multi-stage turbine blades; The guide wheel base includes a guide wheel housing and a first guide wheel shaft, the guide wheel housing is connected to the first guide wheel blade and the second guide wheel blade respectively, the first guide wheel blade is arranged on the first guide wheel shaft, and the first guide wheel shaft is connected to the isolation sleeve; The multi-stage guide wheel includes a first unit and a second unit, and the first unit and the second unit can be assembled into the complete multi-stage guide wheel; The driving device further includes a snap ring and a positioning nut. The snap ring is sleeved on the isolation sleeve, and a raised ring is provided on the end face of the snap ring. The positioning nut is sleeved on the first guide wheel shaft and is threadedly connected to the isolation sleeve. The inner wall of the first guide wheel shaft is provided with a groove matching the raised ring; The first unit and the second unit are sleeved on the isolation sleeve, and the positioning nut pushes the first guide wheel axis toward the clamping ring until the raised ring is inserted into the clamping groove; One end of the positioning nut away from the isolation sleeve is a conical surface, and the conical surface is perpendicular to the working surface of the first guide wheel blade.

10. A method for processing a multi-stage guide wheel according to claim 9, characterized in that: include: Mounting the processed first guide wheel and the second guide wheel on the supporting core shaft, aligning the first guide wheel and the second guide wheel, wherein the second guide wheel includes a second guide wheel base and a second guide wheel blade; Put the limit stopper on the support core shaft, and screw the lock nut into the support core shaft; After aligning the limit block with the first guide wheel, tighten the lock nut and push it into the protective sleeve as a whole until the limit block abuts against the end surface of the protective sleeve; Rotate the protective sleeve until it is aligned with the limit stopper; After the blades of the first guide wheel and the blades of the second guide wheel are initially fixed to the protective sleeve by gluing or welding, the lock nut is unscrewed, the limit block and the supporting core shaft are removed, and the semi-finished guide wheel is obtained; The semi-finished guide wheel is cut into two halves along the axis, and then the blades of the first guide wheel and the second guide wheel blades are spot welded and reinforced with the protective sleeve. Finally, the second guide wheel base is removed by processing to obtain a multi-stage guide wheel.

11. The method for processing a multi-stage guide wheel according to claim 10, wherein: Aligning the first guide wheel with the second guide wheel includes: making a first positioning mark on the first guide wheel, making a second positioning mark on the second guide wheel, and aligning the first positioning mark with the second positioning mark; Aligning the limit block piece with the first guide wheel includes: making a third limit mark on the limit block piece, and aligning the third limit mark with the first positioning mark; The aligning of the protective sleeve with the limit block includes: making a fourth positioning mark on the protective sleeve, and aligning the fourth limit mark with the third limit mark.

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