A magnetic bearing purification and protection system

Abstract

This invention relates to the field of magnetic bearing technology, solving the problem of magnetic levitation bearings being easily damaged by impurities and particulate matter. It proposes a magnetic bearing purification and protection system, including a magnetic levitation bearing installed in an expander. The magnetic levitation bearing is connected to a main shaft, which is fixedly connected to an impeller in the expansion chamber of the expander. An air chamber is provided around the expansion chamber, connected to it via an air inlet perpendicular to the impeller shaft. The air outlet direction of the expansion chamber is along the impeller shaft towards the outside of the expander. The impeller is equipped with a throttling orifice device to remove impurities from the magnetic levitation bearing. The inlet of the air chamber is connected to a filter purification device to remove impurities and particulate matter from the gas. This invention ensures the stable operation of the magnetic levitation bearing and the safe operation of the system.

Description

Technical Field

[0001] This invention relates to the field of magnetic bearing technology, and in particular to a magnetic bearing purification and protection system. Background Technology

[0002] In the petrochemical industry, magnetic levitation bearings, as an advanced bearing technology, have been widely used in various rotating machinery due to their significant advantages such as high precision, low friction, high speed, and low noise. With the continuous development of the petrochemical industry, higher demands are placed on the operational stability, reliability, and efficiency of equipment. Advances in magnetic levitation bearing technology are constantly driving the overall performance improvement of the industry, enabling equipment to operate stably under more complex and harsher conditions, providing strong support for the efficient operation of petrochemical production. In the past, conventional methods were often used to ensure the normal operation of magnetic levitation bearings. Regarding bearing support, traditionally, ordinary sliding bearings or other types of non-magnetic levitation bearings were relied upon. However, when a magnetic levitation bearing fails, these ordinary bearings cannot quickly and effectively provide temporary support, potentially leading to sudden equipment shutdown. In terms of gas purification, the conventional approach is to use a simple single-stage filter to initially filter the gas entering the magnetic levitation bearing. However, this method is insufficient to effectively remove impurities and particulate matter of different particle sizes from the gas. Previously, there was a lack of targeted devices and measures for pressure control and particulate matter discharge, making it difficult to accurately control pressure differences and effectively remove particles from relevant chambers, allowing impurities and particulate matter to easily enter the bearing area. Simultaneously, there was a lack of effective real-time monitoring methods for the operating status and gas cleanliness of magnetic levitation bearings, making it difficult to detect potential problems in a timely manner. However, these existing technologies have significant shortcomings. Ordinary support bearings cannot respond quickly and provide stable temporary support when magnetic levitation bearings fail, easily causing equipment damage and downtime. Single-stage filters have limited filtration efficiency and cannot adequately remove impurities and particulate matter from the gas, affecting the service life and operational stability of magnetic levitation bearings. The lack of effective pressure control and particulate matter discharge devices allows impurities and particulate matter to accumulate in the bearing area, further exacerbating bearing wear and increasing the risk of failure. Moreover, the lack of real-time monitoring devices makes it impossible to detect abnormal magnetic levitation bearing operation or substandard gas cleanliness in a timely manner, preventing the implementation of protective measures and thus affecting normal equipment operation and production efficiency. Summary of the Invention

[0003] This invention solves the problem of magnetic levitation bearings being easily damaged by impurities and particulate matter, and proposes a magnetic bearing purification and protection system to ensure the stable operation of magnetic levitation bearings and the safe operation of the system.

[0004] To achieve the above objectives, the following technical solution is proposed:

[0005] A magnetic bearing purification and protection system includes a magnetic levitation bearing installed in an expander. The magnetic levitation bearing is connected to a main shaft. The main shaft is located in the expansion chamber of the expander and is fixedly connected to an impeller. An air chamber is provided around the expansion chamber. The air chamber is connected to the expansion chamber through an air inlet. The air inlet is perpendicular to the impeller shaft. The air outlet direction of the expansion chamber is along the impeller shaft towards the outside of the expander. The impeller is provided with a throttling orifice device to remove impurities from the magnetic levitation bearing. The inlet of the air chamber is connected to a filter purification device to remove impurities and particulate matter from the gas.

[0006] This invention is equipped with a filtration and purification device and a throttling orifice device, which effectively prevents impurities and particulate matter from entering the magnetic levitation bearing area, protects the magnetic levitation bearing from damage, and extends its service life. The protection device of this invention has a simple structure, is easy to install and maintain, has low cost, and has high practicality and promotion value.

[0007] Preferably, the main shaft is connected to an auxiliary bearing on the side of the magnetic levitation bearing away from the impeller.

[0008] This invention effectively protects magnetic levitation bearings by incorporating an auxiliary bearing, a filtration and purification device, and a throttling orifice, effectively preventing impurities and particulate matter from entering the magnetic levitation bearing area, thus protecting it from damage and extending its service life. This invention also ensures continuous equipment operation: in the event of magnetic levitation bearing failure, it automatically switches to the auxiliary bearing, ensuring continuous equipment operation, reducing downtime, and improving equipment operating efficiency.

[0009] Preferably, the auxiliary bearing is a rolling ball bearing, which includes an inner ring, an outer ring, and rolling balls disposed on the inner and outer rings, wherein the rolling balls are ceramic balls.

[0010] The bearing inner ring of this invention is fixed to the main shaft, and the auxiliary bearing uses ceramic balls, with a load-bearing capacity of up to 3×10⁻⁶. 6 The DN bearing, with a rotor clearance of 0.15mm, supports and guides machine rotation with minimal friction, transferring loads between machine components. It provides high precision and low friction, enabling high speeds while reducing noise and energy consumption. The auxiliary bearing provides temporary support in case of magnetic bearing failure, preventing sudden equipment shutdown due to bearing damage, protecting the equipment from damage, and ensuring a rapid response to magnetic bearing failure. The ceramic balls make point contact with the raceway of the bearing's inner ring, as per reference. Figure 3 As the load acting on the bearing increases, the contact point becomes an elliptical area. A smaller contact area results in less rolling friction, allowing the ball bearing to adapt to high-speed operation. The auxiliary bearing of this invention can withstand five landings at full speed, nominal load, and nominal coasting conditions, as well as over 100 short-term contacts.

[0011] Preferably, the outer ring of the bearing is fitted with a damping metal corrugated strip soft liner, and the auxiliary bearing is connected to the bearing housing fixed on the expander through the damping metal corrugated strip soft liner.

[0012] The damping metal corrugated strip liner of this invention is a flexible material installed between the outer ring of a bearing and the bearing housing to reduce the stiffness of the bearing. The elastic deformation capacity of the liner reduces the bearing stiffness and provides damping to suppress rotation.

[0013] Preferably, the impeller includes an impeller seat and a plurality of blades circumferentially distributed along the axis of the impeller seat, and the throttling orifice device includes a plurality of throttling orifices circumferentially distributed along the axis of the impeller seat.

[0014] Preferably, the throttling orifice is located in the middle of the impeller seat to 50% to 70% of the outer diameter of the impeller seat.

[0015] In this invention, the impeller seat is fixedly connected to the main shaft. Throttling orifices are typically located in the region from the middle of the impeller seat to 50% to 70% of its outer diameter. These orifices also help balance axial forces, and the number can reach 4 to 12 evenly distributed orifices. The throttling orifices on the impeller seat control the pressure difference. High-pressure gas enters the cavity, and the gas flow carries particles out of the impeller back cavity, i.e., the area between the impeller seat and the magnetic levitation bearing, reducing the possibility of impurities and particles entering the bearing area.

[0016] Preferably, the filtration and purification device includes a multi-stage filtration unit, which is provided with a coarse filtration unit, a medium filtration unit, and a fine filtration unit according to the size of the filtered particles, from large to small.

[0017] The coarse filtration unit is used to remove large particulate impurities from the gas, the medium filtration unit is used to remove medium particulate impurities from the gas, and the fine filtration unit is used to remove tiny particulate impurities from the gas. Through multi-stage filtration, the cleanliness of the gas entering the magnetic levitation bearing is ensured to meet the requirements.

[0018] Preferably, the device includes a detection apparatus, which comprises a sensor and a monitoring system. The sensor is mounted on the magnetic levitation bearing and the filtration and purification device, and the monitoring system analyzes and processes the data collected by the sensor and issues an alarm signal.

[0019] Preferably, the monitoring system is equipped with a fault diagnosis module. When the fault diagnosis module determines that the magnetic levitation bearing is malfunctioning or the gas cleanliness is insufficient based on a preset threshold, it issues an alarm signal and activates corresponding protection measures.

[0020] Preferably, the monitoring device integrates a data storage module, which records historical gas cleanliness data and magnetic levitation bearing operating parameters for maintenance cycle prediction and fault source analysis.

[0021] The beneficial effects of this invention are:

[0022] 1. Effective protection of magnetic levitation bearings: By setting up auxiliary bearings, filtration and purification devices and throttling devices, impurities and particulate matter are effectively prevented from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage and extending its service life.

[0023] 2. Ensure continuous equipment operation: When the magnetic levitation bearing fails, it can automatically switch to the auxiliary bearing to ensure continuous equipment operation, reduce equipment downtime, and improve equipment operating efficiency.

[0024] 3. Simple structure and easy to implement: The protective device of the present invention has a simple structure, is easy to install and maintain, has low cost, and has high practicality and promotion value. Attached Figure Description

[0025] Figure 1 This is a system configuration diagram of the present invention.

[0026] Figure 2 This is a cross-sectional view of the impeller of the present invention.

[0027] Figure 3 This is a schematic diagram of the auxiliary bearing of the present invention.

[0028] The components are: 1. Magnetic levitation bearing; 2. Main shaft; 3. Auxiliary bearing; 4. Air chamber; 5. Expansion chamber; 6. Air inlet; 7. Impeller; 8. Throttling orifice; 9. Impeller seat; 10. Blade; 31. Rolling ball; 32. Bearing outer ring; 33. Damping metal corrugated soft liner. Detailed Implementation Example

[0029] This embodiment proposes a magnetic bearing purification and protection system, referencing... Figure 1 and Figure 2 The expansion chamber includes a magnetic levitation bearing 1 installed in the expander, the magnetic levitation bearing 1 being connected to a main shaft 2, the main shaft 2 being fixedly connected to an impeller 7 in the expansion chamber 5 of the expander, an air chamber 4 being provided around the expansion chamber 5, the air chamber 4 being connected to the expansion chamber 5 through an air inlet 6, the air inlet 6 being perpendicular to the axis of the impeller 7, the air outlet direction of the expansion chamber 5 being along the axis of the impeller 7 towards the outside of the expander, the impeller 7 being provided with a throttling orifice device for removing impurities from the magnetic levitation bearing 1, and a filtration and purification device for removing impurities and particulate matter from the gas being connected to the inlet of the air chamber 4.

[0030] This invention incorporates a filtration and purification device and a throttling orifice device to effectively prevent impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage and extending its service life. The protective device of this invention has a simple structure, is easy to install and maintain, and has low cost, making it highly practical and worthy of widespread application. The main shaft 2 is located on the side of the magnetic levitation bearing 1 furthest from the impeller 7 and is connected to an auxiliary bearing 3. This invention effectively protects the magnetic levitation bearing by incorporating an auxiliary bearing, a filtration and purification device, and a throttling orifice device, effectively preventing impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage, and extending its service life. This invention ensures continuous equipment operation: in the event of magnetic levitation bearing failure, it can automatically switch to the auxiliary bearing, ensuring continuous equipment operation, reducing downtime, and improving equipment operating efficiency.

[0031] The impeller 7 includes an impeller seat 9 and a plurality of blades 10 circumferentially distributed along the axis of the impeller seat 9. The throttling orifice device includes a plurality of throttling orifices 8 circumferentially distributed along the axis of the impeller seat 9. The throttling orifices 8 are located from the middle of the impeller seat 9 to 50% to 70% of the outer diameter of the impeller seat 9.

[0032] In this invention, the impeller seat 9 is fixedly connected to the main shaft 2. Throttling orifices are typically located in the middle of the impeller seat 9, extending to 50%–70% of its outer diameter. These orifices can balance axial forces and can number from 4 to 12 evenly distributed orifices. Throttling orifices 8 are located on the impeller seat 9 and are used to control the pressure difference. High-pressure gas enters the cavity, and the gas flow carries particles out of the impeller back cavity, i.e., the area between the impeller seat 9 and the magnetic levitation bearing 1, reducing the possibility of impurities and particles entering the bearing area.

[0033] Working principle of pressure control of orifice device:

[0034] Source of high-pressure gas: High-pressure gas from the impeller inlet enters the impeller back cavity through a throttling orifice. The orifice diameter is typically 3-6 mm, much smaller than the pipe diameter. As the airflow passes through, a pressure drop Δp occurs due to local resistance. According to Bernoulli's equation, the relationship between the pressure difference Δp and the flow rate Q is:

[0035] ;

[0036] Where: C d Here, A is the flow coefficient and A is the orifice area. The density of the gas;

[0037] The dynamic equilibrium reached is as follows: when the pressure inside the cavity increases, the gas flow rate through the throttling orifice increases, carrying away more pressure; conversely, the flow rate decreases and the pressure rises again.

[0038] refer to Figure 3The auxiliary bearing 3 is a rolling ball bearing, which includes an inner ring, an outer ring, and rolling balls 31 disposed on the inner and outer rings 32. The rolling balls 31 are ceramic balls. A damping metal corrugated strip soft liner 33 is fitted on the outer side of the outer ring 32. The auxiliary bearing is connected to the bearing housing fixed on the expander through the damping metal corrugated strip soft liner 33.

[0039] The rolling ball bearing of this invention replaces sliding friction with the rotational motion of the rolling elements, thereby reducing contact resistance and wear. The rotational frequency w depends on the mass m and stiffness (k). In this invention, the inner ring of the bearing is fixed to the main shaft, and the auxiliary bearing uses ceramic balls, with a load-bearing capacity of up to 3×10⁻⁶. 6 The DN bearing, with a rotor clearance of 0.15mm, supports and guides machine rotation with minimal friction, transferring loads between machine components. It provides high precision and low friction, enabling high speeds while reducing noise and energy consumption. The auxiliary bearing provides temporary support in case of magnetic bearing failure, preventing sudden equipment shutdown due to bearing damage, protecting the equipment from damage, and ensuring a rapid response to magnetic bearing failure. The ceramic balls make point contact with the raceway of the bearing's inner ring, as per reference. Figure 3 As the load acting on the bearing increases, the contact point becomes an elliptical area. A smaller contact area results in less rolling friction, allowing the ball bearing to adapt to high-speed operation. The auxiliary bearing of this invention can withstand five landings at full speed, nominal load, and nominal coasting conditions, as well as over 100 short-term contacts.

[0040] The damping metal corrugated strip soft liner 33 of this invention is a flexible material installed between the outer ring of the bearing and the bearing housing to reduce the stiffness of the bearing. The elastic deformation capability of the soft liner reduces the bearing stiffness and provides damping to suppress rotation. Example

[0041] This embodiment optimizes the filtration device based on Embodiment 1, proposing a magnetic bearing purification and protection system, referencing... Figure 1 and Figure 2 The expansion chamber includes a magnetic levitation bearing 1 installed in the expander, the magnetic levitation bearing 1 being connected to a main shaft 2, the main shaft 2 being fixedly connected to an impeller 7 in the expansion chamber 5 of the expander, an air chamber 4 being provided around the expansion chamber 5, the air chamber 4 being connected to the expansion chamber 5 through an air inlet 6, the air inlet 6 being perpendicular to the axis of the impeller 7, the air outlet direction of the expansion chamber 5 being along the axis of the impeller 7 towards the outside of the expander, the impeller 7 being provided with a throttling orifice device for removing impurities from the magnetic levitation bearing 1, and a filtration and purification device for removing impurities and particulate matter from the gas being connected to the inlet of the air chamber 4.

[0042] This invention incorporates a filtration and purification device and a throttling orifice device to effectively prevent impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage and extending its service life. The protective device of this invention has a simple structure, is easy to install and maintain, and has low cost, making it highly practical and worthy of widespread application. The main shaft 2 is located on the side of the magnetic levitation bearing 1 furthest from the impeller 7 and is connected to an auxiliary bearing 3. This invention effectively protects the magnetic levitation bearing by incorporating an auxiliary bearing, a filtration and purification device, and a throttling orifice device, effectively preventing impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage, and extending its service life. This invention ensures continuous equipment operation: in the event of magnetic levitation bearing failure, it can automatically switch to the auxiliary bearing, ensuring continuous equipment operation, reducing downtime, and improving equipment operating efficiency.

[0043] The filtration and purification device includes a multi-stage filtration unit, which is provided with a coarse filtration unit, a medium filtration unit, and a fine filtration unit according to the size of the filtered particles, from large to small.

[0044] The coarse filtration unit removes large particulate impurities from the gas, the medium filtration unit removes medium-sized particulate impurities, and the fine filtration unit removes tiny particulate impurities. Through multi-stage filtration, the cleanliness of the gas entering the magnetic levitation bearing is ensured to meet the requirements. Large particulate impurities have a diameter range of ≥20 micrometers; medium-sized particulate impurities have a diameter range of 1-20 micrometers; and tiny particulate impurities have a diameter range of ≤1 micrometer.

[0045] The impeller 7 includes an impeller seat 9 and a plurality of blades 10 circumferentially distributed along the axis of the impeller seat 9. The throttling orifice device includes a plurality of throttling orifices 8 circumferentially distributed along the axis of the impeller seat 9. The throttling orifices 8 are located from the middle of the impeller seat 9 to 50% to 70% of the outer diameter of the impeller seat 9.

[0046] In this invention, the impeller seat 9 is fixedly connected to the main shaft 2. Throttling orifices are typically located in the middle of the impeller seat 9, extending to 50%–70% of its outer diameter. These orifices can balance axial forces and can number from 4 to 12 evenly distributed orifices. Throttling orifices 8 are located on the impeller seat 9 and are used to control the pressure difference. High-pressure gas enters the cavity, and the gas flow carries particles out of the impeller back cavity, i.e., the area between the impeller seat 9 and the magnetic levitation bearing 1, reducing the possibility of impurities and particles entering the bearing area.

[0047] Working principle of pressure control of orifice device:

[0048] Source of high-pressure gas: High-pressure gas from the impeller inlet enters the impeller back cavity through a throttling orifice. The orifice diameter is typically 3-6 mm, much smaller than the pipe diameter. As the airflow passes through, a pressure drop Δp occurs due to local resistance. According to Bernoulli's equation, the relationship between the pressure difference Δp and the flow rate Q is:

[0049]

[0050] Where: C d Here, A is the flow coefficient and A is the orifice area. The density of the gas;

[0051] The dynamic equilibrium reached is as follows: when the pressure inside the cavity increases, the gas flow rate through the throttling orifice increases, carrying away more pressure; conversely, the flow rate decreases and the pressure rises again.

[0052] refer to Figure 3 The auxiliary bearing 3 is a rolling ball bearing, which includes an inner ring, an outer ring, and rolling balls 31 disposed on the inner and outer rings 32. The rolling balls 31 are ceramic balls. A damping metal corrugated strip soft liner 33 is fitted on the outer side of the outer ring 32. The auxiliary bearing is connected to the bearing housing fixed on the expander through the damping metal corrugated strip soft liner 33.

[0053] The rolling ball bearing of this invention replaces sliding friction with the rotational motion of the rolling elements, thereby reducing contact resistance and wear. The rotational frequency w depends on the mass m and stiffness (k). In this invention, the inner ring of the bearing is fixed to the main shaft, and the auxiliary bearing uses ceramic balls, with a load-bearing capacity of up to 3×10⁻⁶. 6 The DN bearing, with a rotor clearance of 0.15mm, supports and guides machine rotation with minimal friction, transferring loads between machine components. It provides high precision and low friction, enabling high speeds while reducing noise and energy consumption. The auxiliary bearing provides temporary support in case of magnetic bearing failure, preventing sudden equipment shutdown due to bearing damage, protecting the equipment from damage, and ensuring a rapid response to magnetic bearing failure. The ceramic balls make point contact with the raceway of the bearing's inner ring, as per reference. Figure 3 As the load acting on the bearing increases, the contact point becomes an elliptical area. A smaller contact area results in less rolling friction, allowing the ball bearing to adapt to high-speed operation. The auxiliary bearing of this invention can withstand five landings at full speed, nominal load, and nominal coasting conditions, as well as over 100 short-term contacts.

[0054] The damping metal corrugated strip soft liner 33 of this invention is a flexible material installed between the outer ring of the bearing and the bearing housing to reduce the stiffness of the bearing. The elastic deformation capability of the soft liner reduces the bearing stiffness and provides damping to suppress rotation. Example

[0055] This embodiment adds a monitoring device to Embodiment 2, proposing a magnetic bearing purification and protection system, referencing... Figure 1 and Figure 2The expansion chamber includes a magnetic levitation bearing 1 installed in the expander, the magnetic levitation bearing 1 being connected to a main shaft 2, the main shaft 2 being fixedly connected to an impeller 7 in the expansion chamber 5 of the expander, an air chamber 4 being provided around the expansion chamber 5, the air chamber 4 being connected to the expansion chamber 5 through an air inlet 6, the air inlet 6 being perpendicular to the axis of the impeller 7, the air outlet direction of the expansion chamber 5 being along the axis of the impeller 7 towards the outside of the expander, the impeller 7 being provided with a throttling orifice device for removing impurities from the magnetic levitation bearing 1, and a filtration and purification device for removing impurities and particulate matter from the gas being connected to the inlet of the air chamber 4.

[0056] This invention incorporates a filtration and purification device and a throttling orifice device to effectively prevent impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage and extending its service life. The protective device of this invention has a simple structure, is easy to install and maintain, and has low cost, making it highly practical and worthy of widespread application. The main shaft 2 is located on the side of the magnetic levitation bearing 1 furthest from the impeller 7 and is connected to an auxiliary bearing 3. This invention effectively protects the magnetic levitation bearing by incorporating an auxiliary bearing, a filtration and purification device, and a throttling orifice device, effectively preventing impurities and particulate matter from entering the magnetic levitation bearing area, protecting the magnetic levitation bearing from damage, and extending its service life. This invention ensures continuous equipment operation: in the event of magnetic levitation bearing failure, it can automatically switch to the auxiliary bearing, ensuring continuous equipment operation, reducing downtime, and improving equipment operating efficiency.

[0057] The filtration and purification device includes a multi-stage filtration unit, which is provided with a coarse filtration unit, a medium filtration unit, and a fine filtration unit according to the size of the filtered particles, from large to small.

[0058] The coarse filtration unit removes large particulate impurities from the gas, the medium filtration unit removes medium-sized particulate impurities, and the fine filtration unit removes tiny particulate impurities. Through multi-stage filtration, the cleanliness of the gas entering the magnetic levitation bearing is ensured to meet the requirements. Large particulate impurities have a diameter range of ≥20 micrometers; medium-sized particulate impurities have a diameter range of 1-20 micrometers; and tiny particulate impurities have a diameter range of ≤1 micrometer.

[0059] The impeller 7 includes an impeller seat 9 and a plurality of blades 10 circumferentially distributed along the axis of the impeller seat 9. The throttling orifice device includes a plurality of throttling orifices 8 circumferentially distributed along the axis of the impeller seat 9. The throttling orifices 8 are located from the middle of the impeller seat 9 to 50% to 70% of the outer diameter of the impeller seat 9.

[0060] In this invention, the impeller seat 9 is fixedly connected to the main shaft 2. Throttling orifices are typically located in the middle of the impeller seat 9, extending to 50%–70% of its outer diameter. These orifices can balance axial forces and can number from 4 to 12 evenly distributed orifices. Throttling orifices 8 are located on the impeller seat 9 and are used to control the pressure difference. High-pressure gas enters the cavity, and the gas flow carries particles out of the impeller back cavity, i.e., the area between the impeller seat 9 and the magnetic levitation bearing 1, reducing the possibility of impurities and particles entering the bearing area.

[0061] Working principle of pressure control of orifice device:

[0062] Source of high-pressure gas: High-pressure gas from the impeller inlet enters the impeller back cavity through a throttling orifice. The orifice diameter is typically 3-6 mm, much smaller than the pipe diameter. As the airflow passes through, a pressure drop Δp occurs due to local resistance. According to Bernoulli's equation, the relationship between the pressure difference Δp and the flow rate Q is:

[0063]

[0064] Where: C d Here, A is the flow coefficient and A is the orifice area. The density of the gas;

[0065] The dynamic equilibrium reached is as follows: when the pressure inside the cavity increases, the gas flow rate through the throttling orifice increases, carrying away more pressure; conversely, the flow rate decreases and the pressure rises again.

[0066] refer to Figure 3 The auxiliary bearing 3 is a rolling ball bearing, which includes an inner ring, an outer ring, and rolling balls 31 disposed on the inner and outer rings 32. The rolling balls 31 are ceramic balls. A damping metal corrugated strip liner 33 is fitted around the outer ring 32, and the auxiliary bearing is connected to a bearing housing fixed on the expander via the damping metal corrugated strip liner 33. The rolling ball bearing of this invention uses the rotational motion of the rolling elements to replace sliding friction, thereby reducing contact resistance and wear. The rotational frequency w depends on the mass m and stiffness (k). In this invention, the inner ring of the bearing is fixed to the main shaft, and the auxiliary bearing uses ceramic balls, with a load-bearing capacity of up to 3×10⁻⁶. 6 The DN bearing, with a rotor clearance of 0.15mm, supports and guides machine rotation with minimal friction, transferring loads between machine components. It provides high precision and low friction, enabling high speeds while reducing noise and energy consumption. The auxiliary bearing provides temporary support in case of magnetic bearing failure, preventing sudden equipment shutdown due to bearing damage, protecting the equipment from damage, and ensuring a rapid response to magnetic bearing failure. The ceramic balls make point contact with the raceway of the bearing's inner ring, as per reference. Figure 3As the load acting on the bearing increases, the contact point becomes an elliptical area. A smaller contact area results in less rolling friction, allowing the ball bearing to adapt to high-speed operation. The auxiliary bearing of this invention can withstand five landings at full speed, nominal load, and nominal coasting conditions, as well as over 100 short-term contacts.

[0067] The damping metal corrugated strip soft liner 33 of this invention is a flexible material installed between the outer ring of the bearing and the bearing housing to reduce the stiffness of the bearing. The elastic deformation capability of the soft liner reduces the bearing stiffness and provides damping to suppress rotation.

[0068] This embodiment also includes a detection device, which comprises a sensor and a monitoring system. The sensor is installed on the magnetic levitation bearing and the filtration and purification device. The monitoring system analyzes and processes the data collected by the sensor and issues an alarm signal. The monitoring system is equipped with a fault diagnosis module. When the fault diagnosis module determines, based on a preset threshold, that the magnetic levitation bearing is malfunctioning or the gas cleanliness is insufficient, it issues an alarm signal and activates corresponding protective measures. The monitoring device integrates a data storage module, which records historical gas cleanliness data and magnetic levitation bearing operating parameters for maintenance cycle prediction and fault tracing analysis.

Claims

1. A magnetic bearing purification and protection system, characterized in that, The expansion chamber includes a magnetic levitation bearing (1) connected to a main shaft (2). The main shaft (2) is fixedly connected to an impeller (7) in the expansion chamber (5) of the expansion chamber. An air chamber (4) is provided around the expansion chamber (5). The air chamber (4) is connected to the expansion chamber (5) through an air inlet (6). The air inlet (6) is perpendicular to the axis of the impeller (7). The air outlet direction of the expansion chamber (5) is along the axis of the impeller (7) towards the outside of the expansion chamber. The impeller (7) is equipped with a mechanism to remove impurities from the magnetic levitation bearing. (1) The throttling orifice device, the inlet of the gas chamber (4) is connected to a filtration and purification device for removing impurities and particulate matter in the gas; the impeller (7) includes an impeller seat (9) and a number of blades (10) distributed circumferentially along the axis of the impeller seat (9); the throttling orifice device includes a number of throttling orifices (8) distributed circumferentially along the axis of the impeller seat (9); the filtration and purification device includes a multi-stage filtration unit, the multi-stage filtration unit is provided with a coarse filtration unit, a medium filtration unit and a fine filtration unit respectively according to the size of the filtered particles from large to small.

2. The magnetic bearing purification and protection system according to claim 1, characterized in that, The main shaft (2) is located on the side of the magnetic levitation bearing (1) away from the impeller (7) and is connected to an auxiliary bearing (3).

3. The magnetic bearing purification and protection system according to claim 2, characterized in that, The auxiliary bearing (3) is a rolling ball bearing, which includes an inner ring, an outer ring, and rolling balls (31) disposed in the inner ring and the outer ring (32). The rolling balls (31) are ceramic balls.

4. The magnetic bearing purification and protection system according to claim 3, characterized in that, The outer ring (32) of the bearing is fitted with a damping metal corrugated strip soft liner (33), and the auxiliary bearing is connected to the bearing housing fixed on the expander through the damping metal corrugated strip soft liner (33).

5. The magnetic bearing purification and protection system according to claim 1, characterized in that, The throttling orifice (8) is located in the middle of the impeller seat (9) and extends to 50% to 70% of the outer diameter of the impeller seat (9).

6. The magnetic bearing purification and protection system according to claim 1, characterized in that, The device includes a monitoring unit, which comprises a sensor and a monitoring system. The sensor is mounted on the magnetic levitation bearing and the filtration and purification device. The monitoring system analyzes and processes the data collected by the sensor and issues an alarm signal.

7. A magnetic bearing purification and protection system according to claim 6, characterized in that, The monitoring system is equipped with a fault diagnosis module. When the fault diagnosis module determines that the magnetic levitation bearing is malfunctioning or the gas cleanliness is insufficient based on a preset threshold, it issues an alarm signal and activates corresponding protection measures.

8. A magnetic bearing purification and protection system according to claim 6 or 7, characterized in that, The monitoring device integrates a data storage module, which records historical gas cleanliness data and magnetic levitation bearing operating parameters for maintenance cycle prediction and fault source analysis.

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