Transmission connection structure of permanent magnet coupling direct-driven slurry pump

Abstract

The invention belongs to the field of petroleum drilling, and particularly relates to a permanent magnet coupler direct-drive slurry pump transmission connection structure which comprises a motor, the output end of the motor is connected with a motor hollow rotating shaft, and a permanent magnet coupler is arranged in the hollow rotating shaft; an outer rotor of the permanent magnet coupler is fixedly connected with a motor hollow rotating shaft, and an inner rotor is fixedly connected with a slurry pump power rotating shaft. The non-contact transmission mode effectively isolates vibration generated by a load, ensures that the motor operates more stably, remarkably improves the stability of the whole system, and avoids heat accumulation and energy loss generated by friction and abrasion of a traditional coupler. Compared with a traditional double-layer structure and a four-layer structure, the number of effective magnetic poles is multiplied, the air gap magnetic flux density is remarkably enhanced, the maximum torque output is improved, the structural design is optimized, and the power transmission requirement of the slurry pump under the large-torque working condition is effectively met.

Description

Technical Field

[0001] The invention belongs to the field of oil drilling, and in particular relates to a transmission connection structure of a permanent magnetic coupling directly driven mud pump. Background Art

[0002] Mud pumps are essential equipment in oilfield drilling, carrying the crucial task of transporting mud. Traditional mud pumps typically use a motor connected to the pump body via a coupling for power transmission. However, these couplings present numerous operational drawbacks. Firstly, traditional couplings utilize a contact transmission mechanism. Over long-term operation, contact friction can cause significant wear and tear. This not only requires frequent replacement of coupling components, increasing maintenance costs, but also creates debris that can enter the mud pump system, impacting normal operation. Secondly, heat accumulation from contact friction can easily lead to overheating of the equipment, impacting its performance and service life. Furthermore, load-generated vibrations are directly transmitted to the motor through traditional couplings, impacting its stability and reducing the reliability of the entire system. Existing permanent magnet couplings, which often utilize a double-layer magnet structure, offer insufficient torque density and are unable to meet the high power requirements of mud pumps.

[0003] Therefore, developing a new type of coupling to improve the transmission performance of the mud pump has important practical significance.

[0004] In view of this, this invention is proposed. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a permanent magnet coupling direct-drive mud pump transmission connection structure, which is mainly used to solve the problem that traditional couplings produce a lot of wear due to contact transmission during long-term operation, which not only requires frequent replacement of coupling components and increases maintenance costs, but also causes debris to enter the mud pump system due to wear, affecting the normal operation of the pump body.

[0006] The present invention provides a permanent magnet coupling direct-drive mud pump transmission connection structure, comprising a motor, wherein the output end of the motor is connected to the hollow rotating shaft of the motor, and a permanent magnet coupling is arranged inside the hollow rotating shaft; the two ends of the permanent magnet coupling are respectively fixedly connected to the hollow rotating shaft of the motor and the power rotating shaft of the mud pump.

[0007] Specifically, the permanent magnet coupling includes an outer rotor outer yoke and an inner rotor yoke. The outer rotor outer yoke is configured to be cylindrical and a first permanent magnet is provided on the inner wall. The inner rotor yoke of the permanent magnet coupling is configured to be cylindrical and nested inside the outer rotor yoke. A second permanent magnet corresponding to the first permanent magnet is provided on the inner rotor yoke. The outer rotor yoke is fixedly connected to the hollow shaft of the motor, and the inner rotor yoke is fixedly connected to the power shaft of the mud pump.

[0008] Specifically, an outer rotor inner yoke is arranged inside the outer rotor outer yoke, and the outer rotor inner yoke is coaxial with the outer rotor outer yoke and is cylindrical. The inner side wall of the outer rotor outer yoke and the outer wall of the inner rotor yoke are both provided with outer permanent magnets, and the side wall of the outer rotor inner yoke and the inner wall of the inner rotor yoke are both provided with inner permanent magnets, wherein the outer permanent magnets of the inner rotor correspond to the outer permanent magnets of the outer rotor, and the inner permanent magnets of the inner rotor are opposite to the inner permanent magnets of the outer rotor.

[0009] Specifically, different magnetic poles of the permanent magnets on the inner rotor and the outer rotor are arranged alternately, and the magnetization directions of the permanent magnets are all along the radial direction of the inner yoke of the outer rotor.

[0010] Specifically, the distance between the inner rotor permanent magnet and the outer rotor permanent magnet of the permanent magnet coupling is 0.1 mm to 0.5 mm.

[0011] Specifically, the outer rotor yoke is fixedly connected to the hollow rotating shaft of the motor through a connecting flange, and the inner rotor yoke is fixedly connected to the power rotating shaft of the mud pump through a shaft sleeve.

[0012] Specifically, the permanent magnet is made of high-performance rare earth permanent magnet material neodymium iron boron permanent magnet.

[0013] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0014] (1) The present invention provides a permanent magnetic coupling direct-drive mud pump transmission connection structure, in which the output end of the motor is connected to the hollow shaft of the motor, and a permanent magnetic coupling is provided inside the hollow shaft; the outer rotor end face of the permanent magnetic coupling is fixedly connected to the hollow shaft of the motor, and the inner rotor end face is fixedly connected to the mud pump power shaft. When the hollow shaft of the motor drives the outer rotor of the permanent magnetic coupling to rotate, the synchronous rotation of the inner rotor of the permanent magnetic coupling is achieved based on the magnetic coupling effect. This process realizes non-contact power transmission between the hollow shaft of the motor and the power shaft of the mud pump. This non-contact transmission method effectively isolates the vibration generated by the load, ensures smoother operation of the motor, and significantly improves the stability of the entire system; it also reduces the heat accumulation and energy loss caused by friction and wear in traditional couplings.

[0015] (2) The permanent magnet coupling of the present invention adopts a four-layer surface-mounted permanent magnet design. Both the outer rotor and the inner rotor adopt a double-layer permanent magnet nested layout. At the same time, the inner rotor is reinforced with a carbon steel yoke iron interlayer to enhance the magnetic-mechanical coupling effect, improve the magnetic field stability and torque transmission capability. Compared with the traditional two-layer structure, the four-layer structure doubles the number of effective magnetic poles, significantly enhances the magnetic flux density, and improves the maximum torque output. This structural design optimization effectively meets the power transmission requirements of the mud pump under high-torque conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the invention.

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 This is a schematic structural diagram of a direct-drive mud pump based on a permanent magnetic coupling according to the present invention;

[0019] Figure 2 This is a cross-sectional view of the structural model of the four-layer permanent magnetic coupling of the present invention;

[0020] Figure 3 It is a schematic diagram of the structure of two layers of permanent magnets in the prior art;

[0021] Figure 4 This is a schematic diagram of the four-layer permanent magnet structure of the present invention.

[0022] in:

[0023] 1. Mud pump power shaft; 2. Bushing; 3. Inner rotor; 4. Permanent magnet coupling; 5. Motor; 6. Outer rotor; 7. Connecting flange; 8. Motor hollow shaft; 9. Inner permanent magnet of outer rotor; 10. Inner yoke of outer rotor; 11. Inner permanent magnet of inner rotor; 12. Inner rotor yoke; 13. Outer permanent magnet of inner rotor; 14. Outer permanent magnet of outer rotor; 15. Outer yoke of outer rotor. DETAILED DESCRIPTION

[0024] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of arrangements consistent with certain aspects of the present invention as detailed in the appended claims.

[0025] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention is described in further detail below with reference to the accompanying drawings and embodiments.

[0026] Example 1

[0027] refer to Figure 1 and Figure 2The present invention provides a permanent magnet coupling direct-drive mud pump transmission connection structure, including a motor 5, the output end of the motor 5 is connected to the hollow rotating shaft 8 of the motor, and a permanent magnet coupling 4 is arranged inside the hollow rotating shaft; the outer rotor 6 of the permanent magnet coupling 4 is fixedly connected to the hollow rotating shaft 8 of the motor, and the inner rotor 3 is fixedly connected to the mud pump power rotating shaft 1; when the hollow rotating shaft 8 of the motor drives the outer rotor 6 of the permanent magnet coupling 4 to rotate, the magnetic field generated by the permanent magnets on the outer rotor 6 of the permanent magnet coupling 4 acts on the permanent magnets on the inner rotor 3 of the permanent magnet coupling 4, thereby realizing the synchronous rotation of the inner rotor 3 of the permanent magnet coupling 4 based on the magnetic coupling effect, and the non-contact transmission method reduces the heat accumulation and wear caused by friction in the traditional coupling.

[0028] refer to Figures 1 to 3 The permanent magnet coupling 4 includes an outer rotor outer yoke 15 and an inner rotor yoke 12. The outer rotor outer yoke 15 is configured to be cylindrical and a first permanent magnet is provided on the inner wall. The inner rotor yoke 12 of the permanent magnet coupling 4 is configured to be cylindrical and nested inside the outer rotor yoke 6. A second permanent magnet corresponding to the first permanent magnet is provided on the inner rotor yoke 12. The outer rotor yoke 6 is fixedly connected to the hollow shaft 8 of the motor, and the inner rotor yoke 12 is fixedly connected to the mud pump power shaft 1.

[0029] In addition, the different magnetic poles of the permanent magnets on the rotor are arranged alternately, and the magnetization direction of the permanent magnets is along the radial direction of the inner yoke 10 of the outer rotor, which can improve the utilization rate of the permanent magnets and increase the torque transmission efficiency.

[0030] In this embodiment, the air gap between the permanent magnets of the inner rotor 3 and the outer rotor 6 of the permanent magnet coupling 4 is 0.5 mm to 1 mm, preferably 0.8 mm. In this case, the air gap has good transmission and heat dissipation efficiency.

[0031] The outer rotor 6 yoke of the permanent magnet coupling 4 is preferably fixedly connected to the motor hollow shaft 8 via a connecting flange 7 , and the inner rotor yoke 12 is fixedly connected to the mud pump power shaft 1 via a shaft sleeve 2 .

[0032] In this embodiment, the permanent magnet is made of high-performance rare earth permanent magnet material, preferably neodymium iron boron permanent magnet, which can provide sufficient magnetic flux and magnetic field strength; the yoke iron material is made of carbon steel, which can improve the stability of the inner rotor 3 and the outer rotor 6 while enhancing the magnetic-mechanical coupling effect.

[0033] The use process of the permanent magnetic coupling direct-drive mud pump transmission connection structure in the above embodiment is as follows:

[0034] Turn on the motor 5, and the motor hollow shaft 8 is powered by the motor 5 to rotate, while driving the outer rotor 6 of the permanent magnetic coupling 4 to rotate through the connecting flange 7. The inner rotor 3 drives the mud pump to rotate synchronously due to the magnetic field coupling effect to perform drilling operations.

[0035] Example 2

[0036] refer to Figure 2 and Figure 4 The difference between this embodiment and embodiment 1 is that: in this embodiment, an outer rotor inner yoke 10 is arranged inside the outer rotor outer yoke 15, and the outer rotor inner yoke 10 is coaxial with the outer rotor outer yoke 15 and is cylindrical. The inner side wall of the outer rotor outer yoke 15 and the outer wall of the inner rotor yoke 12 are both provided with outer permanent magnets, and the side wall of the outer rotor inner yoke 10 and the inner wall of the inner rotor yoke 12 are both provided with inner permanent magnets, wherein the inner rotor outer permanent magnet 13 corresponds to the outer rotor outer permanent magnet 14, and the inner rotor inner permanent magnet 11 is opposite to the outer rotor inner permanent magnet 9. On the one hand, the inner rotor 3 of the permanent magnet coupling 4 of the present invention adopts a four-layer surface-mounted permanent magnet design, which can provide a stronger magnetic field and torque transmission capability, thereby improving the transmission efficiency and workload capacity of the system; on the other hand, the inner rotor 3 adopts a sandwich composite structure of double-layer permanent magnets + yoke iron interlayer, and the double-layer permanent magnets are reinforced by the yoke iron interlayer, which enhances the magnetic-mechanical coupling effect and improves the magnetic field stability and torque transmission capability.

[0037] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0038] It should be understood that the present invention is not limited to the above description and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A permanent magnetic coupling direct drive mud pump transmission connection structure, characterized in that: The invention comprises a motor (5), wherein the output end of the motor (5) is connected to a hollow rotating shaft (8) of the motor, and a permanent magnetic coupling (4) is provided inside the hollow rotating shaft; and the two ends of the permanent magnetic coupling (4) are respectively fixedly connected to the hollow rotating shaft (8) of the motor and the power rotating shaft (1) of the mud pump.

2. The transmission connection structure of the permanent magnetic coupling direct-drive mud pump according to claim 1, characterized in that: The permanent magnetic coupling (4) comprises an outer rotor outer yoke (15) and an inner rotor yoke (12); the outer rotor outer yoke (15) is arranged in a cylindrical shape and has a first permanent magnet arranged on its inner side wall; the inner rotor yoke (12) of the permanent magnetic coupling (4) is arranged in a cylindrical shape and is nested inside the yoke of the outer rotor (6); a second permanent magnet corresponding to the first permanent magnet is arranged on the inner rotor yoke (12); the outer rotor yoke is fixedly connected to the hollow shaft (8) of the motor; and the inner rotor yoke (12) is fixedly connected to the power shaft (1) of the mud pump.

3. The transmission connection structure of the permanent magnetic coupling direct-drive mud pump according to claim 2, characterized in that: An outer rotor inner yoke (10) is arranged inside the outer rotor outer yoke (15), the outer rotor inner yoke (10) is coaxial with the outer rotor outer yoke (15) and is cylindrical, the inner side wall of the outer rotor outer yoke (15) and the outer wall of the inner rotor yoke (12) are both provided with outer permanent magnets, the side wall of the outer rotor inner yoke (10) and the inner wall of the inner rotor yoke (12) are both provided with inner permanent magnets, wherein the inner rotor outer permanent magnet (13) corresponds to the outer rotor outer permanent magnet (14), and the inner rotor inner permanent magnet (11) corresponds to the outer rotor inner permanent magnet (9).

4. The transmission connection structure of a direct-drive mud pump with a permanent magnetic coupling according to claim 3, characterized in that: The inner rotor (3) adopts a sandwich composite structure of double-layer permanent magnets and yoke iron interlayers.

5. The transmission connection structure of a direct-drive mud pump with a permanent magnetic coupling according to claim 2 or 3, characterized in that: The different magnetic poles of the permanent magnets on the inner rotor (3) and the outer rotor (6) are arranged alternately, and the magnetization directions of the permanent magnets are all along the radial direction of the inner yoke (10) of the outer rotor.

6. The transmission connection structure of a direct-drive mud pump with a permanent magnetic coupling according to claim 2 or 3, characterized in that: The distance between the permanent magnet of the inner rotor (3) and the permanent magnet of the outer rotor (6) of the permanent magnet coupling (4) is 0.1 mm to 0.5 mm.

7. The transmission connection structure of a direct-drive mud pump with a permanent magnetic coupling according to claim 2 or 3, characterized in that: The outer rotor (6) yoke is fixedly connected to the motor hollow shaft (8) via a connecting flange (7), and the inner rotor yoke (12) is fixedly connected to the mud pump power shaft (1) via a shaft sleeve (2).

8. The transmission connection structure of a direct-drive mud pump with a permanent magnetic coupling according to claim 1, characterized in that: The permanent magnet is made of high-performance rare earth permanent magnet material, neodymium iron boron permanent magnet.

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