Corrosion resistant sealed vacuum transfer pump

Abstract

The present application relates to the technical field of vacuum transmission equipment, in particular to a kind of corrosion-resistant sealed vacuum transmission pump, including motor for providing driving source, still including: pumping unit, including the pump body of detachably installed with packing bulkhead at both ends, two rotors are rotatably installed in pump body, first end cover, detachably installed on inner end side packing bulkhead, it is equipped with driving shaft hole and packing flange groove being arranged coaxially, shaft body gland flange is detachably installed at packing flange groove;Magnetic coupling unit is used for the shaft rod of any rotor being equipped with coaxial connection motor output shaft and shaft rod, shaft rod is inserted in driving shaft hole;The corrosion-resistant sealed vacuum transmission pump, sealing element has corrosion-resistant function, it is favorable to improve equipment service life, it is applicable to strong corrosion, low leakage, anti-powder pollution uranium enrichment engineering application;Equipped with lubricating oil cavity can cooperate with magnetic coupling unit to obtain sealed shaft transmission structure, it is favorable to reduce penetration point, reduce the leakage rate of complete machine.

Description

Technical Field

[0001] This invention relates to the field of vacuum transfer equipment technology, and specifically to a corrosion-resistant, sealed vacuum transfer pump. Background Technology

[0002] In uranium enrichment projects, vacuum transfer pumps are the main equipment for conveying uranium hexafluoride (UF6) and hydrogen fluoride (HF) media. These media are highly corrosive, and corrosion or leaks can not only interrupt the process but also pose safety risks. In addition, the media transport is accompanied by small amounts of metal or non-metal powder, which can easily wear down the pump chamber and affect its service life.

[0003] In current uranium enrichment projects, the mainstream vacuum transport equipment is divided into two categories: one is the centrifugal vacuum pump, which uses a high-speed rotating impeller to apply centrifugal force to gas molecules to achieve transport. Although it is small in size and has a high pumping speed, it has a weak ability to pressurize low molecular weight gases. Uranium enrichment requires a high compression ratio for low molecular weight gases, which actually requires multiple stages of equipment in series, resulting in high cost, large space occupation, and significant limitations. The other is the Roots vacuum pump, which transports gas by periodically changing the pump chamber volume. It has consistent compression efficiency for media of different molecular weights and is adapted to the characteristics of process media. However, this type of equipment has a large dynamic seal leakage, and long-term operation is prone to failure due to wear or corrosion, which can induce direct contact between process media and lubricating oil, causing pollution problems.

[0004] In summary, while existing equipment can meet basic process requirements, it cannot fully adapt to the harsh working conditions of uranium enrichment projects, which require strong corrosion, low leakage, and resistance to powder contamination, in terms of corrosion resistance, sealing, and reliability. Therefore, we propose a corrosion-resistant, sealed vacuum transfer pump. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings mentioned in the background section and provide a corrosion-resistant, sealed vacuum transfer pump.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A corrosion-resistant sealed vacuum transfer pump includes an electric motor for providing a drive source, and further includes:

[0008] The pumping unit includes a pump body with detachable encapsulation partitions at both ends, and two rotors are rotatably mounted inside the pump body.

[0009] The first end cap is detachably installed on the inner end side of the encapsulation partition plate and is provided with a coaxially arranged drive shaft hole and encapsulation flange groove. A shaft cover flange is detachably installed at the encapsulation flange groove.

[0010] A magnetic coupling unit is used to coaxially connect the motor output shaft and a shaft provided on any of the rotors, wherein the shaft is inserted into the drive shaft hole;

[0011] When the motor rotates, it drives the rotor to rotate through the magnetic coupling unit.

[0012] Preferably, the magnetic coupling unit includes a sealing isolation sleeve that is detachably installed on the outer end of the shaft cover flange to form a closed cavity;

[0013] An inner magnetic cylinder for coaxial connection with the shaft is inserted inside the sealing isolation sleeve, and an outer magnetic cylinder for coaxial mounting on the output shaft of the motor is fitted outside the sealing isolation sleeve.

[0014] When the outer magnetic cylinder rotates, the inner magnetic cylinder is driven by magnetic force to cause the rotor to rotate synchronously.

[0015] Preferably, the encapsulation partition is provided with a pivot hole for inserting the shaft, and a dynamic sealing groove and a pressure sealing groove arranged sequentially outward along the pivot hole;

[0016] The dynamic sealing groove and the pressure sealing groove are respectively equipped with dynamic sealing elements and conical sealing rings for fitting onto the shaft.

[0017] Preferably, a lubricating oil cavity is provided between the first end cap and the corresponding side of the encapsulation partition, and the lubricating oil cavity is provided with a vacuum joint.

[0018] Preferably, at least one of the rotor surfaces is provided with grooves for collecting powder.

[0019] Preferably, the two rotors are arranged in a figure-eight shape, perpendicularly attached to each other, for synchronous rotation in opposite directions.

[0020] Preferably, the outer end of the first end cover is detachably fitted with a connecting flange for fixing the motor.

[0021] Preferably, each of the outer ends of the encapsulation partition can be detachably installed with a limiting sleeve corresponding to the shaft, and a bearing is installed between the limiting sleeve and the shaft;

[0022] The limiting sleeve is used to keep the shaft centered and stable and to compress the conical sealing ring to maintain a seal.

[0023] Preferably, a second end cap is detachably installed at the outer end of the encapsulation partition;

[0024] The second end cover has two coaxial synchronous gears mounted on the two shafts for meshing transmission.

[0025] Preferably, rubber sealing rings are installed at the connection points between the two encapsulation partitions and the pump body, as well as the first end cover and the second end cover;

[0026] Both the rubber sealing ring and the conical sealing ring are made of fluorine-resistant rubber material;

[0027] The dynamic sealing element is a magnetohydrodynamic sealing element.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. This corrosion-resistant sealed vacuum transfer pump has corrosion-resistant seals and rotor grooves that collect powder during rotation, avoiding repeated friction damage and improving equipment lifespan. It is suitable for uranium enrichment engineering applications requiring strong corrosion, low leakage, and resistance to powder contamination.

[0030] 2. The lubricating oil chamber can work with the magnetic coupling unit to obtain a sealed shaft transmission structure, which helps to reduce the seepage point and lower the overall leakage rate. Furthermore, the lubricating oil chamber can maintain the internal and external pressure difference balance, avoiding dynamic seal leakage caused by pressure difference, which helps to ensure the sealing performance of the whole machine and plays a lubricating role during rotation. Attached Figure Description

[0031] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0032] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0033] Figure 2 This is one of the exploded views of the overall structural installation relationship of the present invention;

[0034] Figure 3 This is the second exploded view of the overall structural installation relationship of the present invention;

[0035] Figure 4 This is the third exploded view of the overall structural installation relationship of the present invention;

[0036] Figure 5 This is one of the cross-sectional schematic diagrams of the overall structure of the present invention;

[0037] Figure 6 This is the second sectional view of the overall structure of the present invention;

[0038] Figure 7 This is an exploded cross-sectional view of the overall structure of the present invention;

[0039] Figure 8 This is a cross-sectional view of the partial installation relationship of the present invention;

[0040] Figure 9 This is a schematic diagram of the partial installation relationship of the present invention;

[0041] Figure 10 This is a diagram showing the installation relationship between the first end cap and the encapsulation partition of the present invention;

[0042] Figure 11 This is a schematic diagram of the installation of the motor, magnetic coupling unit, and rotor of the present invention;

[0043] Figure 12 This is an exploded view showing the installation relationship between the motor, magnetic coupling unit, and rotor of the present invention.

[0044] Figure 13 This is a schematic diagram showing the installation relationship of the two rotors in this invention.

[0045] The meanings of the labels in the diagram are as follows:

[0046] 1. Motor; 2. Connecting flange cover;

[0047] 3. First end cap; 31. Vacuum fitting; 301. Drive shaft hole; 302. Lubricating oil chamber; 303. Encapsulation flange groove;

[0048] 4. Magnetic coupling unit; 41. External magnetic cylinder; 42. Sealing isolation sleeve; 43. Internal magnetic cylinder; 5. Pump body; 6. Rotor; 61. Shaft; 601. Groove; 7. Shaft cover flange; 8. Synchronous gear;

[0049] 9. Encapsulation partition; 901. Shaft hole; 91. Dynamic sealing groove; 92. Pressure sealing groove; 10. Second end cover; 11. Dynamic sealing element; 12. Limiting sleeve; 13. Bearing; 14. Conical sealing ring. Detailed Implementation

[0050] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Please see Figures 1-13 The present invention will describe the above technical solution in detail through the following embodiments:

[0052] This embodiment of the vacuum transfer pump includes a motor 1 for providing a drive source, and specifically also includes a pumping unit; the pumping unit includes a pump body 5 with a sealing partition 9 detachably mounted at both its inner and outer ends, and a device such as... is rotatably mounted inside the pump body 5. Figures 4-7 as well as Figure 13 The two rotors 6 shown are arranged in a figure-eight shape, perpendicularly attached to each other, for synchronous rotation in opposite directions.

[0053] It should be explained that in this embodiment, grooves 601 are provided on the surface of rotor 6 for collecting powder. Considering the problem of metal / non-metal powder accumulation caused by friction or media residue during the operation of rotor 6, it is creatively proposed to set grooves on the surface of rotor 6 to collect powder during rotation. By utilizing the principle of fluid dynamics combined with the flow field channel of the pump body 5 (inlet inlet, outlet inlet) and gravity, the powder is discharged. This can effectively avoid repeated wear of powder between rotor 6 and pump body 5 cavity wall, and can also significantly reduce the risk of material thermal fatigue caused by local friction heating, thereby extending the life of rotor 6 and improving the overall operational stability of the equipment.

[0054] In this embodiment, a first end cap 3 is detachably installed on the inner end-side encapsulation partition 9, and a second end cap 10 is detachably installed on the outer end-side encapsulation partition 9. In this embodiment, JY7766 type fluorine-resistant rubber gaskets are placed at the conventional connection surfaces to improve corrosion resistance. Due to the presence of highly reactive fluorides such as hydrogen fluoride and fluorine gas in the light impurities, traditional rubber sealing materials often fail rapidly due to problems such as molecular chain breakage and surface powdering. After being continuously exposed to a 150°C environment with 10% hydrogen fluoride vapor for 500 hours, the tensile strength retention rate of the JY7766 type fluorine-resistant rubber gasket is still above 85%, and the volume expansion rate is less than 3%, which is far superior to the 60% strength retention rate and 8% expansion rate of conventional fluororubber (FKM). It can effectively solve the safety hazards such as sealing failure and equipment leakage caused by fluoride penetration.

[0055] To achieve synchronous counter-rotation of the two rotors 6, two synchronous gears 8 are provided inside the second end cover 10, coaxially mounted on the shafts 61 of the two rotors 6 and meshing with each other; at the same time, the first end cover 3 is provided with... Figure 9 , Figure 10The active shaft hole 301 and the encapsulation flange groove 303 are coaxially arranged. A shaft cover flange 7 is detachably installed at the encapsulation flange groove 303, and a fluorine-resistant rubber gasket is also installed on the connecting surface. In order to enhance the sealing reliability of the insertion position of the encapsulation partition 9 on both sides, this embodiment has a rotating shaft hole 901 for inserting a shaft 61 on the encapsulation partition 9. A dynamic sealing groove 91 and a pressure sealing groove 92 are arranged outward from the rotating shaft hole 901. A dynamic sealing element 11 and a conical sealing ring 14 for fitting on the shaft 61 are respectively installed at the dynamic sealing groove 91 and the pressure sealing groove 92. The conical sealing ring 14 is made of fluorine-resistant rubber material, and the dynamic sealing element 11 is a magnetohydrodynamic sealing element. A limiting sleeve 12 can be encapsulated outside the pressure sealing groove 92. The limiting sleeve 12 is connected to the bearing 13. The corresponding shaft 61 is rotatably connected to maintain the rotational reliability of the shaft 61. After the limit sleeve 12 is tightened, it can compress the conical sealing ring 14 to cooperate with the magnetohydrodynamic seal to maintain the seal between the seal and the shaft body. The magnetohydrodynamic seal uses an external magnetic field to control the magnetic fluid to dynamically adhere to the surface of the shaft 61, which is the rotating shaft, to form a non-contact adaptive sealing interface. This avoids the problem of lubricating oil in the lubricating oil cavity 302 between the first end cover 3 and the encapsulation partition 9 entering the pump cavity and causing contamination. A vacuum joint 31 is provided on the lubricating oil cavity 302, which can evacuate the pressure of the lubricating oil cavity 302 to negative pressure before use, so as to achieve no pressure difference on both sides of the dynamic sealing element 11. The dynamic sealing element 11 is installed close to the bearing 13 to achieve a low leakage rate dynamic seal between the pump cavity and the lubricating oil cavity 302.

[0056] In this embodiment, to achieve good sealing, the connection between the shaft 61 of the rotor 6 and the motor 1 is the core sealing structure. In this embodiment, the output shaft of the motor 1 and a shaft 61 are connected by a magnetic coupling unit 4. The shaft 61 is inserted into the drive shaft hole 301. The outer end of the first end cover 3 is detachably equipped with a connecting flange cover 2 for fixing the motor 1.

[0057] The magnetic coupling unit 4 includes a sealing sleeve 42 that is detachably installed on the outer end of the shaft cover flange 7 to form a closed cavity. An inner magnetic cylinder 43 for coaxial connection with the shaft 61 is inserted inside the sealing sleeve 42. An outer magnetic cylinder 41 for coaxial installation on the output shaft of the motor 1 is fitted outside the sealing sleeve 42. When the motor 1 drives the outer magnetic cylinder 41 to rotate, the inner magnetic cylinder 43 is magnetically pulled to drive the rotor 6 to rotate synchronously.

[0058] The corrosion-resistant sealed vacuum transfer pump of this embodiment works on the following principle: based on the magnetic coupling unit 4, the leakage rate of the connection part is reduced; there is a gap between the outer magnetic cylinder 41, the sealing isolation sleeve 42, and the inner magnetic cylinder 43 of the magnetic coupling, and contactless transmission is achieved through the magnetic field. When working, the output shaft of the motor 1 drives the outer magnetic cylinder 41 to rotate, and the inner magnetic cylinder 43 rotates synchronously with the outer magnetic cylinder 41 under the action of the magnetic field. At the same time, the rotor 6 is driven to rotate synchronously in the opposite direction in the pump body 5 cavity through the shaft 61.

[0059] Specifically, this invention uses a magnetic coupling unit 4 as a transmission mechanism, achieving contactless torque transmission through the action of a magnetic field. This ensures that all structures in contact with uranium hexafluoride and hydrogen fluoride gases are sealed to the external environment by O-ring fluorine-resistant rubber gaskets, effectively guaranteeing the overall leakage rate. The lubricating oil chamber 302 of this invention can be evacuated before use, ensuring that the pressure inside the lubricating oil chamber 302 is consistent with the pressure in the pump body 5, reducing dynamic seal leakage caused by pressure difference. The pump body 5 of this invention is made of aluminum alloy casting, which is resistant to fluoride corrosion and does not require secondary protection processes such as traditional electroplating of nickel-based alloys or spraying of PTFE coatings.

[0060] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0061] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0062] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A corrosion-resistant sealed vacuum transfer pump, comprising a motor (1) for providing a drive source, characterized in that: Also includes: The pumping unit includes a pump body (5) with encapsulation partitions (9) detachably installed at both ends, and two rotors (6) are rotatably installed inside the pump body (5). The first end cap (3) is detachably installed on the inner end side of the encapsulation partition (9), and is provided with a coaxially arranged drive shaft hole (301) and encapsulation flange groove (303). A shaft cover flange (7) is detachably installed at the encapsulation flange groove (303). A magnetic coupling unit (4) is used to coaxially connect the output shaft of the motor (1) and a shaft (61) provided on any of the rotors (6), the shaft (61) being inserted into the drive shaft hole (301); When the motor (1) rotates, the rotor (6) is driven to rotate through the magnetic coupling unit (4); The encapsulation partition (9) is provided with a pivot hole (901) for inserting the shaft (61), and a dynamic sealing groove (91) and a pressure sealing groove (92) arranged sequentially outward along the pivot hole (901). The dynamic sealing groove (91) and the pressure sealing groove (92) are respectively equipped with a dynamic sealing element (11) and a conical sealing ring (14) for fitting on the shaft (61). A lubricating oil cavity (302) is provided between the first end cap (3) and the corresponding side encapsulation partition (9), and a vacuum connector (31) is provided on the lubricating oil cavity (302). Each of the outer ends of the encapsulation partition (9) can be detachably installed with a limiting sleeve (12) corresponding to the shaft (61), and a bearing (13) is installed between the limiting sleeve (12) and the shaft (61). The limiting sleeve (12) is used to keep the shaft (61) centered and stable and to compress the conical sealing ring (14) to maintain a seal.

2. The corrosion-resistant sealed vacuum transfer pump as described in claim 1, characterized in that: The magnetic coupling unit (4) includes a sealing sleeve (42) that is detachably installed on the outer end of the shaft cover flange (7) to form a closed cavity. The sealing isolation sleeve (42) is fitted with an inner magnetic cylinder (43) for coaxial connection with the shaft (61), and the sealing isolation sleeve (42) is fitted with an outer magnetic cylinder (41) for coaxial installation on the output shaft of the motor (1). When the outer magnetic cylinder (41) rotates, the inner magnetic cylinder (43) is driven by magnetic force to cause the rotor (6) to rotate synchronously.

3. The corrosion-resistant sealed vacuum transfer pump as described in claim 1, characterized in that: At least one of the rotors (6) has grooves (601) on its surface for collecting powder.

4. The corrosion-resistant sealed vacuum transfer pump as described in claim 3, characterized in that: The two rotors (6) are arranged in a figure-eight shape with their rotors perpendicular to each other for synchronous rotation in opposite directions.

5. The corrosion-resistant sealed vacuum transfer pump as described in claim 1, characterized in that: The outer end of the first end cover (3) is detachably fitted with a connecting flange cover (2) for fixing the motor (1).

6. The corrosion-resistant sealed vacuum transfer pump as described in claim 1, characterized in that: A second end cap (10) is detachably installed at the outer end of the encapsulation partition (9); The second end cap (10) has two synchronous gears (8) that are coaxially mounted on the two shafts (61) for meshing transmission.

7. The corrosion-resistant sealed vacuum transfer pump as described in claim 6, characterized in that: Rubber sealing rings are installed at the connection points between the two encapsulation partitions (9) and the pump body (5), as well as the first end cover (3) and the second end cover (10); Both the rubber sealing ring and the conical sealing ring (14) are made of fluorine-resistant rubber material; The dynamic sealing element (11) is a magnetohydrodynamic sealing element.

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