Shaft seal flushing structure of water vapor screw compressor unit

Abstract

A shaft seal flushing structure of a steam screw compressor unit comprises a main machine body, a female and male rotor and a rotor end seat, and a female and male rotor shaft neck section extends into the rotor end seat; a shaft seal support is installed in the rotor end base, and shaft seal static ring assemblies are embedded in the two ends of the shaft seal support. A shaft seal shaft sleeve is mounted on the shaft neck section of the female and male rotor; a shaft seal moving ring assembly is sleeved on the shaft seal shaft sleeve; the shaft seal moving ring assembly and the shaft seal support form an annular cavity, and the shaft seal moving ring assembly and the corresponding shaft seal static ring assembly form a mechanical seal friction pair in rotating fit. The rotor end seat and the shaft seal support are provided with a water inlet channel and a water outlet channel which extend to the annular cavity, the water inlet channel and the water outlet channel are connected with an external circulating water flushing system, mechanical sealing parts of the shaft seal can be flushed in real time in the unit operation process, and even if the mechanical sealing parts are abraded, the mechanical sealing parts cannot be damaged. And water vapor medium pollution is not caused in a short time, so that the service life of the shaft seal is prolonged, and stable operation of a water vapor screw compressor unit is guaranteed.

Description

Technical Field

[0001] This utility model relates to sealing components in steam screw compressor units, specifically to a shaft seal flushing structure for steam screw compressor units. Background Technology

[0002] Steam screw compressor units use steam as the compressed medium. They are oil-free screw compressors, and their working principle involves the interaction of a male and female rotor within the main rotor chamber to compress steam and perform work. The key technology for the normal operation of this type of oil-free screw compressor unit lies in the sealing structure that isolates steam and lubricating oil, which significantly impacts the service life of the steam screw compressor. Existing steam screw compressor units typically employ various types of shaft seals at the journals of the male or female rotors, such as gas seals, carbon ring seals, and rotary seals, to ensure the separation of steam and lubricating oil during operation. However, during long-term operation, pressure fluctuations in the sealing gas or mechanical wear of sealing components such as carbon rings can still cause lubricating oil leakage into the steam medium. This results in mixing of lubricating oil and steam, reducing the service life of the lubricating oil and deteriorating the operational stability of the screw compressor unit. To ensure the sealing effect and service life of the shaft seal, the aforementioned mechanical seal components need to be maintained and cleaned in a timely manner. If cleaning is not timely or sufficient, oil and dirt will adhere to the mechanical seal components, leading to a deterioration in the sealing effect and a shortened service life of the sealing device. How to solve the problem of isolating water vapor from lubricating oil, maintain the sealing effect of the shaft seal in a steam screw compressor unit, and effectively extend the working life of the shaft seal structure has always been an important research topic for those skilled in the art. Summary of the Invention

[0003] The purpose of this invention is to provide a shaft seal flushing structure for a steam screw compressor unit, which can flush the mechanical seal components of the shaft seal in real time during unit operation. Even if the mechanical seal components are worn, they will not cause contamination of the steam medium in a short period of time, thereby improving the service life of the shaft seal and ensuring the stable operation of the steam screw compressor unit.

[0004] To achieve the above objectives, the steam screw compressor unit shaft seal flushing structure designed in this utility model includes a main body of the screw compressor, a female or male rotor disposed in the inner cavity of the main body, and a rotor end seat disposed on the outer side of the main body. The journal section of the female or male rotor extends into the bearing hole of the rotor end seat. A shaft seal support is fixedly installed in the bearing hole of the rotor end seat, and shaft seal stationary ring assemblies are embedded at both ends of the shaft seal support. A shaft seal bushing is fixedly installed on the journal section of the female or male rotor, and a shaft seal moving ring assembly is fitted on the shaft seal bushing. An annular cavity is formed between the outer periphery of the shaft seal moving ring assembly and the shaft seal support. The two end faces of the shaft seal moving ring assembly and their corresponding inner end faces of the shaft seal stationary ring assembly form a rotating mechanical seal friction pair.

[0005] Its special feature is that the rotor end seat and shaft seal support are provided with water inlet channels and water outlet channels extending into the annular cavity. The water inlet channels and water outlet channels are connected to the external circulating water flushing system, so that the annular cavity always maintains a certain pressure of circulating flushing fluid. While achieving water sealing of the shaft seal inner cavity, it also completes the water flushing of the shaft seal dynamic ring assembly and the shaft seal stationary ring assembly.

[0006] As a preferred embodiment, a wedge-shaped groove is formed on the end face of the mechanical seal friction pair formed between the rotating ring assembly and the stationary ring assembly. This wedge-shaped groove is used to continuously bring the circulating flushing fluid from the annular cavity into the mechanical seal friction pair. In this way, sufficient flushing fluid is always maintained on the friction surfaces of the rotating and stationary ring assemblies, which are the most difficult to clean, effectively avoiding wear and tear on the mechanical seal components caused by dry friction and significantly improving the service life of the rotating and stationary ring assemblies.

[0007] Furthermore, the wedge-shaped grooves are formed on both end faces of the shaft seal rotating ring assembly. In this way, the shaft seal rotating ring assembly drives the wedge-shaped grooves to rotate actively 360°, which allows the circulating flushing fluid to enter between the mechanical seal friction pairs through the openings of the wedge-shaped grooves.

[0008] Furthermore, the wedge-shaped grooves are provided in multiple layers, and these multiple wedge-shaped grooves are evenly distributed along the circumferential direction of both end faces of the shaft seal moving ring assembly. In this way, the multiple wedge-shaped grooves work together to more effectively introduce a sufficient amount of circulating flushing fluid.

[0009] Furthermore, the number of wedge grooves is preferably set to 8 to 16, with 12 being the optimal setting. In practice, machining 12 wedge grooves on both end faces of the shaft seal dynamic ring assembly has the characteristics of reasonable structure, uniform layout, and balanced force distribution, which is conducive to the complete coverage of the mechanical seal friction pair by the circulating flushing fluid.

[0010] Furthermore, the wedge-shaped grooves are arranged in opposite directions on both end faces of the shaft seal rotating ring assembly. This ensures that the openings and rotation directions of the wedge-shaped grooves on both sides face the flushing fluid, guaranteeing that both mechanical seal friction pairs receive sufficient flushing fluid.

[0011] Furthermore, an annular pressure plate is provided on the outer side of the shaft seal support. The annular pressure plate locks the shaft seal support in the bearing hole of the rotor end seat by screws arranged circumferentially, thereby realizing the axial positioning of the shaft seal dynamic ring assembly and the shaft seal stationary ring assembly.

[0012] This invention has the following advantages: By connecting the external circulating water flushing system to the annular cavity inside the shaft seal, the shaft seal is forced to be constantly filled with circulating flushing fluid. This not only provides real-time water sealing to the inside of the shaft seal but also timely flushes the rotating and stationary ring assemblies, preventing the mechanical seal components from contaminating the lubricating oil. Since the flushing fluid for the mechanical seal components is water, the same as the compression medium in the screw compressor, there is no concern about water vapor contamination by oil. Because there is always sufficient flushing fluid between the friction pairs of the mechanical seal components, there is no concern about damage from dry friction, effectively extending the service life of the shaft seal. Even if the mechanical seal components wear, it will not cause water vapor contamination in a short period, providing valuable time for maintenance and repair, thus ensuring the stable operation of the steam screw compressor unit. This invention is suitable for widespread application in various types of steam screw compressors. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the main cross-sectional structure of a steam screw compressor unit shaft seal flushing structure.

[0014] Figure 2 for Figure 1 A schematic diagram of the A-axis structure of the central sealing ring assembly.

[0015] Figure 3 for Figure 1 A schematic diagram of the B-direction structure of the central shaft sealing ring assembly.

[0016] The components in the diagram are labeled as follows: 1. Main body, 2. Female or male rotor, 3. Shaft seal support, 4. Rotor end seat, 5. Shaft seal moving ring assembly, 6. Water inlet channel, 7. Water outlet channel, 8. Annular cavity, 9. Shaft seal stationary ring assembly, 10. Annular pressure plate, 11. Screw, 12. Shaft seal bushing, 13. Wedge groove. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but these embodiments should not be construed as limiting the present invention.

[0018] like Figures 1 to 3As shown in the figure, this embodiment describes a steam screw compressor unit shaft seal flushing structure, including a main body 1 of the screw compressor, a female or male rotor 2 installed in the inner cavity of the main body 1, and a rotor end seat 4 installed on the outer side of the main body 1. The journal section of the female or male rotor 2 extends into the bearing hole of the rotor end seat 4. A shaft seal support 3 is fixedly installed in the bearing hole of the rotor end seat 4. The shaft seal support 3 is mainly composed of a shaft seal base and a shaft seal outer cylinder (not specifically labeled in the figure). Shaft seal stationary ring assemblies 9 are embedded at both ends of the shaft seal support 3. A shaft seal bushing 12 is fixedly installed on the journal section of the female or male rotor 2. A shaft seal moving ring assembly 5 is fitted on the shaft seal bushing 12. The shaft seal moving ring assembly 5 is mainly composed of left and right moving rings, moving ring springs, moving ring outer cylinders, etc. (not specifically labeled in the figure). An annular cavity 8 is formed between the outer periphery of the shaft seal rotating ring assembly 5 and the shaft seal support 3. The two end faces of the shaft seal rotating ring assembly 5 and the inner end faces of their corresponding shaft seal stationary ring assemblies 9 form a mechanical seal friction pair that rotates together. An annular pressure plate 10 is provided on the outside of the shaft seal support 3. The annular pressure plate 10 secures the shaft seal support 3 in the bearing hole of the rotor end seat 4 by screws 11 arranged circumferentially, thereby achieving axial positioning of the shaft seal rotating ring assembly 5 and the shaft seal stationary ring assembly 9.

[0019] Water inlet channel 6 and water outlet channel 7 extending to the annular cavity 8 are provided on the rotor end seat 4 and shaft seal support 3. The water inlet channel 6 and water outlet channel 7 can be connected to an external circulating water flushing system, so that the annular cavity 8 always maintains a certain pressure of circulating flushing fluid, thereby achieving water sealing of the shaft seal cavity and completing water flushing of the shaft seal dynamic ring assembly 5 and shaft seal stationary ring assembly 9.

[0020] More specifically, a wedge-shaped groove 13 is provided on the end face of the mechanical seal friction pair formed between the shaft seal rotating ring assembly 5 and the shaft seal stationary ring assembly 9. The wedge-shaped groove 13 is used to continuously bring the circulating flushing fluid in the annular cavity 8 into the mechanical seal friction pair. In this way, a sufficient amount of flushing fluid is always maintained on the friction surface of the shaft seal, which is the most difficult to clean, effectively avoiding the wear and tear of the mechanical seal components caused by dry friction, and significantly improving the service life of the shaft seal rotating ring assembly 5 and the shaft seal stationary ring assembly 9.

[0021] In this embodiment, wedge-shaped grooves 13 are formed on the end faces of both sides of the shaft seal rotating ring assembly 5. This allows the shaft seal rotating ring assembly 5 to drive the wedge-shaped grooves 13 to rotate 360° actively, forcing the circulating flushing fluid into the mechanical seal friction pairs through the openings of the wedge-shaped grooves 13. As an optimal design, 12 wedge-shaped grooves 13 are formed on each end face, evenly distributed along the circumference of the end face of the shaft seal rotating ring assembly 5. This design is reasonable, uniformly distributed, and evenly stressed, facilitating comprehensive coverage of the mechanical seal friction pairs by the circulating flushing fluid. Furthermore, the wedge-shaped grooves 13 are arranged in opposite directions on the two end faces of the shaft seal rotating ring assembly 5, ensuring that the openings and rotation directions of the wedge-shaped grooves 13 on both sides face the flushing fluid, guaranteeing that both mechanical seal friction pairs receive a sufficient amount of flushing fluid.

[0022] In summary, the technical solution of this utility model enables real-time water sealing of the shaft seal interior and timely water flushing of the shaft seal dynamic ring assembly and stationary ring assembly, preventing the mechanical seal components of the shaft seal from contaminating the lubricating oil. In particular, the wedge groove 13 ensures that sufficient flushing fluid is always maintained between the mechanical seal friction pair formed by the shaft seal dynamic ring assembly 5 and the shaft seal stationary ring assembly 9, eliminating concerns about damage to the mechanical seal components due to dry friction and significantly improving the service life of the mechanical seal components. This solution is suitable for widespread application in various steam screw compressors.

[0023] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A steam screw compressor unit shaft seal flushing structure, comprising a main body (1) of the screw compressor, a female or male rotor (2) disposed in the inner cavity of the main body (1), and a rotor end seat (4) disposed on the outer side of the main body (1), wherein the journal section of the female or male rotor (2) extends into the bearing hole of the rotor end seat (4); a shaft seal support (3) is fixedly installed in the bearing hole of the rotor end seat (4), and shaft seal stationary ring assemblies (9) are embedded at both ends of the shaft seal support (3); a shaft seal bushing (12) is fixedly installed on the journal section of the female or male rotor (2), and a shaft seal moving ring assembly (5) is fitted on the shaft seal bushing (12); an annular cavity (8) is formed between the outer periphery of the shaft seal moving ring assembly (5) and the shaft seal support (3), and the two end faces of the shaft seal moving ring assembly (5) respectively form a rotating mechanical seal friction pair with the inner end face of the corresponding shaft seal stationary ring assembly (9); characterized in that: The rotor end seat (4) and shaft seal support (3) are provided with water inlet channel (6) and water outlet channel (7) extending to the annular cavity (8). The water inlet channel (6) and water outlet channel (7) are connected to the external circulating water flushing system, so that the annular cavity (8) always maintains a certain pressure of circulating flushing fluid, which achieves water sealing of the shaft seal cavity and completes water flushing of the shaft seal dynamic ring assembly (5) and shaft seal stationary ring assembly (9).

2. The shaft seal flushing structure of the steam screw compressor unit according to claim 1, characterized in that: The mechanical seal friction pair formed between the shaft seal dynamic ring assembly (5) and the shaft seal stationary ring assembly (9) has a wedge-shaped groove (13) on its end face. The wedge-shaped groove (13) is used to continuously bring the circulating flushing fluid in the annular cavity (8) into the mechanical seal friction pair.

3. The shaft seal flushing structure of the steam screw compressor unit according to claim 2, characterized in that: The wedge-shaped groove (13) is formed on both ends of the shaft seal moving ring assembly (5).

4. The shaft seal flushing structure of the steam screw compressor unit according to claim 3, characterized in that: The wedge groove (13) is provided in multiple ways, and the multiple wedge grooves (13) are evenly distributed along the circumferential direction of both end faces of the shaft seal moving ring assembly (5).

5. The shaft seal flushing structure of the steam screw compressor unit according to claim 4, characterized in that: The wedge-shaped groove (13) has 8 to 16 channels.

6. The shaft seal flushing structure of the steam screw compressor unit according to claim 5, characterized in that: The wedge-shaped groove (13) has 12 channels.

7. The steam screw compressor unit shaft seal flushing structure according to any one of claims 3 to 6, characterized in that: The wedge-shaped grooves (13) are arranged in opposite directions on both sides of the shaft seal moving ring assembly (5).

8. The steam screw compressor unit shaft seal flushing structure according to any one of claims 1 to 6, characterized in that: An annular pressure plate (10) is provided on the outside of the shaft seal support (3). The annular pressure plate (10) locks the shaft seal support (3) in the bearing hole of the rotor end seat (4) by screws (11) arranged in the circumferential direction, thereby realizing the axial positioning of the shaft seal dynamic ring assembly (5) and the shaft seal stationary ring assembly (9).

9. The shaft seal flushing structure of the steam screw compressor unit according to claim 7, characterized in that: An annular pressure plate (10) is provided on the outside of the shaft seal support (3). The annular pressure plate (10) locks the shaft seal support (3) in the bearing hole of the rotor end seat (4) by screws (11) arranged in the circumferential direction, thereby realizing the axial positioning of the shaft seal dynamic ring assembly (5) and the shaft seal stationary ring assembly (9).

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