Leak-proof circulating fan in loop type high pressure gas flow calibrating device

Abstract

The application discloses a kind of anti-leakage circulating fans in ring road type high-pressure gas flow calibration device, magnetic coupling shaft coupling includes outer rotor, inner rotor, high-pressure isolation cover and first flange plate;The end of outer rotor is provided with accommodating groove, the end of inner rotor is placed in the accommodating groove of outer rotor, and the inner wall of accommodating groove and the outer periphery of inner rotor are respectively circumferentially evenly provided with multiple N-pole and S-pole interval arrangement magnet, so that the number of magnet on outer rotor and inner rotor is equal, and the magnetic pole is opposite at diametral opposite position;High-pressure isolation cover is the thin-walled shell with closed top, is placed between outer rotor and inner rotor, and does not contact with outer rotor and inner rotor.This application changes transmission form and sealing form, not only significantly improves the safety of system, but also effectively reduces maintenance difficulty and cost, improves work efficiency, and has important significance for promoting the development of clean energy technology.

Description

Technical Field

[0001] This invention relates to the field of fan technology, and in particular to a leak-proof circulating fan in a loop-type high-pressure gas flow calibration device. Background Technology

[0002] Currently, the circulating fans used in high-pressure gas flow calibration devices are still conventional industrial fans. The connection between the impeller and motor in these fans is mechanical, which has the following disadvantages: 1. Low safety: In high-pressure gas calibration, the pressure of the gas being tested is usually greater than 1 MPa, and some of these gases are flammable and explosive, such as hydrogen, natural gas, or hydrogen-blended natural gas. Mechanical seals are unlikely to guarantee zero leakage under high pressure, increasing the safety risks during calibration. 2. High maintenance difficulty and cost: The weak point in the sealing of traditional fans is mainly concentrated between the impeller shaft and the volute. Maintaining a tight seal while the impeller is rotating at high speed is difficult. The speed is already very high, and high-speed rotation will further accelerate the aging and wear of the seals. After a period of use, the seals need to be replaced. Frequent disassembly and assembly of the impeller is not only cumbersome, but also easily causes other sealing parts to fail. 3. Small flow range. Since the sealing method of traditional fans cannot guarantee zero leakage of high-pressure gas, in actual verification work, we can only choose to reduce the speed and increase the size of the impeller blades to ensure that the flow requirements required for verification work are met. However, the excessively large impeller size makes it impossible to disassemble the impeller alone. The motor, coupling and impeller must be disconnected, and the volute must be disassembled before the impeller can be taken out for seal replacement, which further increases the overall maintenance difficulty.

[0003] Therefore, how to create a new type of leak-proof circulating fan for a loop-type high-pressure gas flow calibration device is one of the important research and development topics at present. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a leak-proof circulating fan in a ring-type high-pressure gas flow calibration device, which fundamentally solves the leakage problem caused by traditional mechanical seals, improves safety, reduces maintenance difficulty and cost, and expands the flow range of the fan by increasing the rotation speed and reducing the impeller size, thereby overcoming the shortcomings of the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides a leak-proof circulating fan in a loop-type high-pressure gas flow calibration device, comprising a high-speed motor, a magnetic coupling, a fan impeller, a bearing assembly, and a fan volute.

[0006] The impeller is mounted inside the fan casing via a bearing assembly, and the impeller shaft extends outside the fan casing and is connected to the output shaft of a high-speed motor via a magnetic coupling.

[0007] The magnetic coupling includes an outer rotor, an inner rotor, a high-pressure isolation cover, and a first flange;

[0008] The outer rotor has a receiving groove at its end, and the end of the inner rotor is placed in the receiving groove of the outer rotor. Multiple magnets with N poles and S poles are evenly arranged in the circumferential direction on the inner wall of the receiving groove and the outer periphery of the inner rotor, so that the number of magnets on the outer rotor and the inner rotor are equal and the magnetic poles are opposite at their radial relative positions.

[0009] The high-pressure isolation cover is a thin-walled shell with a closed top, placed between the outer rotor and the inner rotor, and does not contact either the outer rotor or the inner rotor. The root of the high-pressure isolation cover is fixedly connected to the first flange and connected to the outer end face of the bearing assembly by bolts.

[0010] As an improvement of the present invention, the top of the high-pressure isolation cover is conical or flat, and the bottom of the receiving groove is conformally shaped to the top of the high-pressure isolation cover.

[0011] Furthermore, the magnets on the inner rotor are connected to the inner rotor via a second flange and bolts.

[0012] Furthermore, the bearing assembly includes a bearing housing and a high-speed bearing. The back of the fan volute has a stepped mounting hole for mounting the bearing assembly. The outer end of the bearing housing has a flange, which is connected to the mounting hole by bolts. The shaft of the fan impeller is mounted on the bearing housing via the high-speed bearing, and the diameter of the fan impeller is smaller than the diameter of the bearing housing, so that the fan impeller can be installed or removed from the back of the fan volute together with the bearing assembly.

[0013] Furthermore, the bearing assembly is equipped with a speed sensor and a bearing temperature sensor to monitor the fan impeller speed and bearing temperature.

[0014] Furthermore, the fan casing includes an air inlet assembly and an air outlet assembly. The air inlet assembly and the air outlet assembly are axially aligned and connected by bolts. The opposite end faces of the air inlet assembly and the air outlet assembly are machined with annular semi-circular flow channels. After being assembled, they form annular flow channels. The air inlet is located at the axial front end of the air inlet assembly, and the air outlet is located at the upper end of the air outlet assembly.

[0015] Furthermore, the high-speed motor is mounted on an adjustable base, which is provided with a slide rail for adjusting the horizontal position and vertical height of the high-speed motor.

[0016] Furthermore, the magnet is made of neodymium iron boron or samarium cobalt;

[0017] Furthermore, the high-pressure isolation cover is made of non-metallic composite material.

[0018] Furthermore, the high-pressure isolation cover is made of carbon fiber composite material.

[0019] With this design, the present invention has at least the following advantages:

[0020] 1. This invention uses a magnetic coupling to transmit torque between the impeller shaft and the motor output shaft via a magnetic field, avoiding direct physical contact. It also uses a high-pressure isolation cover to form a closed cavity, transforming the original dynamic seal into a static seal, which effectively improves sealing performance and safety, and achieves zero leakage of the high-pressure gas being tested.

[0021] 2. The top of the high-voltage isolation cover is conical and pointed, and the bottom of the receiving groove of the moving rotor is conformed to the top of the high-voltage isolation cover, making it easier to position during installation.

[0022] 3. Due to the change in sealing method and the improvement in sealing performance, the high-speed motor can be set to a higher speed. The impeller shape can be numerically simulated and optimized by computational fluid dynamics (CFD) software, so that the impeller diameter is smaller than the bearing assembly size. This allows the impeller and bearing assembly to be removed separately without disassembling the volute, reducing maintenance difficulty, improving work efficiency, and avoiding end face damage that may be caused during the disassembly of the volute.

[0023] 4. The bearing assembly is equipped with a bearing temperature sensor and a speed sensor, which can monitor the bearing temperature and impeller speed in real time. When the preset value is reached, an alarm will be issued to prevent accidents from occurring. Attached Figure Description

[0024] The above is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Figure 1 This is a schematic diagram of the structure of the present invention.

[0026] Figure 2 This is a schematic diagram of the magnetic coupling in this invention.

[0027] Figure 3 This is a schematic diagram of the bearing assembly in this invention.

[0028] Explanation of reference numerals in the attached drawings: 1. High-speed motor; 2. Magnetic coupling; 3. Fan impeller; 4. Inlet assembly; 5. Bearing assembly; 6. Outlet assembly; 7. Adjustable base; 8. Outer rotor; 9. High-pressure isolation cover; 10. First flange; 11. Inner rotor; 12. Magnet; 13. Second flange; 14. Speed ​​sensor; 15. Bearing temperature sensor; 16. High-speed bearing. Detailed Implementation

[0029] Please see Figures 1 to 3 The present invention provides a leak-proof circulating fan in a ring-type high-pressure gas flow calibration device, comprising a high-speed motor 1, a magnetic coupling 2, a fan impeller 3, a fan volute, and a bearing assembly 5.

[0030] The high-speed motor 1 is mounted on an adjustable base 7, which is equipped with a slide rail for adjusting the horizontal position and vertical height of the high-speed motor 1. This not only facilitates the adjustment of the high-speed motor 1 during initial installation, but also allows the high-speed motor 1 to be moved horizontally backward during subsequent maintenance, leaving space for the removal of the fan impeller 3.

[0031] The magnetic coupling 2 is used for non-contact power transmission between the output shaft of the high-speed motor 1 and the rotating shaft of the fan impeller 3.

[0032] The magnetic coupling 2 includes an inner rotor 8, a high-pressure isolation cover 9, a first flange 10, an outer rotor 11, a magnet 12, and a second flange 13.

[0033] One end of the outer rotor 11 is connected to the output shaft of the high-speed motor 1, and the other end has a receiving groove. Multiple magnets 12 are evenly arranged along the circumference of the inner wall of the receiving groove, and the magnets 12 are arranged with N poles and S poles at intervals.

[0034] One end of the inner rotor 8 is connected to the shaft of the fan impeller 3, and the other end is placed in the receiving groove of the outer rotor 11. Multiple magnets 12 with alternating N and S poles are evenly arranged along the circumferential direction on the outer periphery of the inner rotor 8. The inner rotor 8 and the outer rotor 11 have the same number of magnets 12, but at radially opposite positions, the magnetic poles of the magnets 12 on the inner rotor 8 and the outer rotor 11 are opposite.

[0035] In this embodiment, the magnet 12 on the outer rotor 11 is integrated into the inner wall of the receiving groove, while the magnet 12 on the inner rotor 8 is mounted on the outer periphery of the inner rotor 8 via the second flange 13 and bolts. The magnet 12 is made of neodymium iron boron or samarium cobalt.

[0036] The high-pressure isolation cover 9 is a thin-walled shell with a closed top, placed between the outer rotor 11 and the inner rotor 8. That is, the high-pressure isolation cover 9 is sleeved on the outside of the inner rotor 8 and placed together with the inner rotor 8 in the receiving groove of the outer rotor 11, but the high-pressure isolation cover 9 does not contact the inner rotor 8 or the outer rotor 11.

[0037] The base of the high-pressure isolation cover 9 is fixedly connected to the first flange 10, which is connected to the outer end face of the bearing assembly 5 by bolts. The first flange 10 can be customized as a grooved flange, that is, it has an annular groove on the contact surface between the first flange 10 and the bearing assembly 5, and an O-ring is installed to achieve a seal.

[0038] In this embodiment, the top of the high-pressure isolation cover 9 is conical and pointed. The bottom of the receiving groove on the outer rotor 11 is conformable to the top of the high-pressure isolation cover 9, i.e., it is conical in shape and slightly larger in size than the top of the high-pressure isolation cover 9. This design facilitates accurate positioning during installation. In other embodiments, provided that the user's installation site has accurate positioning capabilities, the top of the high-pressure isolation cover 9 can also be made flat, with the bottom of the receiving groove conforming to it.

[0039] The function of the high-pressure isolation cover 9 is to form a sealed cavity, transforming the original dynamic seal into a static seal and improving the overall sealing performance. The high-pressure isolation cover 9 is made of non-metallic composite material, which is carbon fiber composite material in this embodiment. In other embodiments, it can also be other non-metallic composite materials. Its characteristics are that it not only has high strength and stable connection, but also does not affect the magnetic coupling transmission between the outer rotor 11 and the inner rotor 8, and it will not cause heat generation due to magnetic eddy current effect.

[0040] In this embodiment, the fan casing is a split-type casing, including an intake assembly 4 and an exhaust assembly 6. The intake assembly 4 and the exhaust assembly 6 are axially aligned and connected as a whole by high-strength bolts, with O-rings installed on the connecting surfaces to ensure a seal. Both the intake assembly 4 and the exhaust assembly 6 have annular semi-circular flow channels machined on their opposite end faces, forming a complete annular flow channel inside the casing after they are assembled. Both the intake assembly 4 and the exhaust assembly 6 are castings, which are then machined and polished after forming.

[0041] The air inlet is located at the axial front end of the air inlet assembly 4, and the air outlet is located at the upper end of the air outlet assembly 5. Both the air inlet and the air outlet are equipped with flanges. The flanges are designed according to the pressure level of the medium and are manufactured by welding or casting. The structure is optimized using advanced computational fluid dynamics (CFD) software.

[0042] The fan impeller 3 is installed inside the fan casing via the bearing assembly 5. Specifically, in this embodiment, the fan impeller 3 and the bearing assembly 5 are installed on the air outlet assembly 6, the impeller body is located inside the fan casing, and the shaft extends out of the air outlet assembly 6.

[0043] The bearing assembly 5 includes a bearing housing, a high-speed bearing 16, a speed sensor 14, and a bearing temperature sensor 15.

[0044] The air outlet assembly 6 of the fan volute has a stepped mounting hole on its back that extends into the internal flow channel of the volute. The outer end of the bearing housing has a flange with dimensions matching those of the stepped mounting hole, allowing the bearing housing to be placed in the mounting hole and fixed by bolts. An O-ring can be added to the contact gate between the flange and the stepped mounting hole to achieve a seal.

[0045] The shaft of the fan impeller 3 is mounted on the bearing housing via a high-speed bearing 16. The diameter of the fan impeller 3 is smaller than the diameter of the bearing housing, so that the fan impeller 3 can be removed from the mounting hole together with the bearing assembly 5.

[0046] It should be noted that the change in transmission and sealing methods has solved the problem of high-pressure gas leakage. Without leakage concerns, the high-speed motor 1 can be set to a higher speed, thereby reducing the size of the fan impeller 3. After numerical simulation of the impeller shape using computational fluid dynamics (CFD) software, its size is reduced to less than the diameter of the bearing assembly 5. This allows for the removal of the fan impeller 3 and bearing assembly 5 for maintenance without disassembling the inlet assembly 4 and outlet assembly 6.

[0047] The speed sensor 14 and the bearing temperature sensor 15 are both installed on the bearing housing and are used to monitor the fan impeller speed and bearing temperature, respectively. When the preset value is reached, an alarm signal is issued to prevent accidents from occurring.

[0048] This invention, by changing the transmission and sealing methods, not only significantly improves the safety of the system, but also effectively reduces maintenance difficulty and cost and improves work efficiency, which is of great significance for promoting the development of clean energy technology.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, or alterations made by those skilled in the art using the disclosed technical content shall fall within the protection scope of the present invention.

Claims

1. A leak-proof circulating blower in a loop-type high-pressure gas flow calibrating device, characterized by, The high-speed motor, the magnetic coupling shaft, the fan impeller, the bearing assembly and the fan volute are included. The fan impeller is installed in the fan volute through the bearing assembly, the rotating shaft of the fan impeller extends out of the fan volute and is in transmission connection with the output shaft of the high-speed motor through the magnetic coupling shaft. The magnetic coupling shaft includes an outer rotor, an inner rotor, a high-pressure isolation cover and a first flange plate. The end of the outer rotor is provided with a containing groove, the end of the inner rotor is arranged in the containing groove of the outer rotor, and a plurality of N-pole and S-pole interval arranged magnets are respectively arranged on the inner wall of the containing groove and the outer periphery of the inner rotor in a circumferential uniform manner, so that the number of magnets on the outer rotor and the inner rotor is equal, and the magnetic poles at the diametrically opposite positions are opposite. The high-pressure isolation cover is a thin-walled shell with a closed top, which is arranged between the outer rotor and the inner rotor and does not contact the outer rotor and the inner rotor, the root of the high-pressure isolation cover is fixedly connected with the first flange plate and connected with the outer end surface of the bearing assembly through bolts. The top of the high-pressure isolation cover is in the shape of a tapered pointed top, the groove bottom of the containing groove is conformal to the top of the high-pressure isolation cover, and is used for accurate positioning during installation. The bearing assembly includes a bearing seat and a high-speed bearing, the back of the fan volute is provided with a stepped mounting hole for mounting the bearing assembly, so that the bearing seat is arranged in the mounting hole, the outer end of the bearing seat is provided with a flange, and the flange is connected with the mounting hole through bolts, the rotating shaft of the fan impeller is installed on the bearing seat through the high-speed bearing, and the diameter of the fan impeller is smaller than the diameter of the bearing seat, so that the fan impeller can be installed or dismounted together with the bearing assembly from the back of the fan volute. The high-speed motor is installed on an adjustable base, the adjustable base is provided with sliding rails for adjusting the horizontal position and vertical height of the high-speed motor, and the high-speed motor can be horizontally retreated to leave space for dismounting the fan impeller during subsequent maintenance.

2. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 1, characterized in that, The magnets on the inner rotor are connected with the inner rotor through the second flange plate and bolts.

3. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 1, characterized in that, The bearing assembly is provided with a rotating speed sensor and a bearing temperature sensor for monitoring the rotating speed of the fan impeller and the temperature of the bearing.

4. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 1, characterized in that, The fan volute includes an air inlet assembly and an air outlet assembly, the air inlet assembly and the air outlet assembly are axially opposite and connected through bolts, the opposite end faces of the air inlet assembly and the air outlet assembly are both processed with annular semicircular flow channels, the air inlet is arranged at the axially front end of the air inlet assembly, and the air outlet is arranged at the upper end of the air outlet assembly.

5. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 1, characterized in that, The material of the magnets is neodymium iron boron or samarium cobalt.

6. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 1, characterized in that, The material of the high-pressure isolation cover is a non-metallic composite material.

7. A leak-proof circulating fan in a looped high-pressure gas flow calibration device according to claim 6, characterized in that, The material of the high-pressure isolation cover is a carbon fiber composite material.

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