A mechanical shaft neck seal for a fan

Abstract

The utility model relates to fan sealing technical field discloses a kind of fan mechanical journal sealing devices, including shell, main shaft, first shell and second shell are respectively installed on shell and main shaft, first shell and second shell have preset gap between, second shell can rotate with main shaft relative to first shell, the side of first shell and second shell relatively in axial direction is equipped with multiple convex parts and recesses, convex part and recess embedded type cooperation form fluid attenuation passage, the utility model will fluid attenuation passage be set between first shell and second shell, avoid the problem of gap expansion caused by direct friction of stationary part and rotating main shaft in traditional sealing, first shell and second shell between multiple concave-convex cooperation structure are formed fluid attenuation passage and play the role of throttling, sealing performance is significantly improved.

Description

Technical Field

[0001] This utility model relates to the field of fan sealing technology, and in particular to a fan mechanical journal sealing device. Background Technology

[0002] In industries such as building materials, metallurgy, and power, high-temperature centrifugal fans are key equipment for conveying high-temperature gases. Their operating efficiency and system stability directly affect production energy consumption and safety. Due to the pressure difference between the inside of the casing and the atmosphere, in order to prevent air from the atmospheric side from entering the casing and causing an increase in system air leakage, which would affect the fan's operating efficiency and system power consumption, heat consumption, and other indicators, the airtightness requirements for the journal end seal of the high-temperature fan are very high.

[0003] Typical high-temperature fan sealing devices use a mechanical labyrinth structure and asbestos packing for sealing. This labyrinth structure itself has poor airtightness. Furthermore, after the fan has been running for a period of time, friction occurs between the asbestos packing and the main shaft, increasing the gap between them. Atmospheric gas can then enter the fan casing through this gap. This not only affects the safety of the operating system but also reduces the fan's operating efficiency, increasing system power and heat consumption. Utility Model Content

[0004] The purpose of this invention is to provide a sealing device for the mechanical journal of a fan, so as to solve the problems in the prior art, increase the airtightness of the fan, and more effectively solve the leakage problem at the shaft end of a high-temperature fan.

[0005] This utility model provides a sealing device for the mechanical journal of a wind turbine, comprising:

[0006] chassis;

[0007] The main shaft extends axially through the housing and outwards from the housing.

[0008] The sealing assembly includes a first housing and a second housing, which are respectively mounted on the machine housing and the main shaft. There is a preset gap between the first housing and the second housing. The second housing can rotate relative to the first housing with the main shaft. The first housing and the second housing are provided with multiple protrusions and recesses on opposite sides along the axial direction. The protrusions and the recesses are fitted together to form a fluid attenuation channel.

[0009] In the fan mechanical journal sealing device described above, preferably, the second housing has a plurality of annular grooves on the side facing the first housing, and a sealing sleeve is provided in the grooves, with the end of the sealing sleeve facing away from the second housing abutting against the surface of the first housing.

[0010] In the wind turbine mechanical journal sealing device described above, preferably, the inner ring of the sealing sleeve is provided with an elastic element to limit the sealing sleeve within the groove.

[0011] In the wind turbine mechanical journal sealing device described above, preferably, the end of the first housing near the casing radially at least partially covers the corresponding end of the second housing, and the end of the second housing away from the casing radially covers the corresponding end of the first housing.

[0012] In the fan mechanical journal sealing device described above, preferably, the end of the second housing opposite to the housing is provided with an extension in the circumferential direction, the extension protruding from the outer wall of the first housing and extending to one side of the housing.

[0013] In the wind turbine mechanical journal sealing device described above, preferably, the first housing is symmetrically divided into two halves along the axial direction, and the first housing is connected to the casing by a first fastener.

[0014] In the wind turbine mechanical journal sealing device described above, preferably, the first fastener includes a flange, the flange having a split structure, and the flange being fixedly connected to the housing.

[0015] In the wind turbine mechanical journal sealing device described above, preferably, the second housing is symmetrically divided into two halves along the axial direction, and the second housing is connected to the main shaft by a second fastener.

[0016] Compared with the prior art, this utility model sets the fluid attenuation channel between the first housing and the second housing, avoiding the problem of gap expansion caused by direct friction between the stationary part and the rotating spindle in traditional seals. Multiple concave and convex mating structures are set between the first housing and the second housing to form a fluid attenuation channel, which plays a throttling role and significantly improves the sealing performance. In addition, with the sealing sleeve and elastic pre-tightening to seal the gap, a small amount of residual gas is physically intercepted, resulting in a better sealing effect. Attached Figure Description

[0017] Figure 1 This is an axial half-sectional view of the fan mechanical journal sealing device provided in an embodiment of this utility model;

[0018] Figure 2 This is a cross-sectional view of the fan mechanical journal sealing device provided in an embodiment of this utility model.

[0019] Explanation of reference numerals in the attached figures:

[0020] 10. Housing;

[0021] 20. Spindle;

[0022] 30. Sealing assembly; 31. First housing; 32. Second housing; 320. Groove; 321. Extension; 33. Protrusion; 34. Recess; 35. Fluid attenuation channel; 36. Sealing sleeve; 37. Elastic element;

[0023] 40. First fastener; 41. Second fastener. Detailed Implementation

[0024] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0025] See Figure 1 As shown, the main shaft 20 is the most critical dynamic sealing part of the high-temperature fan. The main shaft 20 penetrates the casing 10, with one end connected to the output component and the other end connected to the motor or coupling. Due to the temperature change before and after the high-temperature fan starts operating, the casing expands upward due to heat. Therefore, in this scenario, a relatively large gap needs to be left between the fan casing 10 and the main shaft 20 during installation. Atmospheric air will leak into the fan casing 10 through this gap, affecting the operating efficiency of the fan and increasing system power consumption and heat consumption. Figure 1 The right side of the image represents the atmospheric side, and the left side represents the casing 10 side. Existing sealing devices use mechanical labyrinth structures or asbestos packing for sealing. For example, a main shaft 20 passes through a sealing seat, which is connected to the casing 10. Multiple comb teeth are set inside the sealing seat, or asbestos packing is used for sealing. However, with long-term use, the asbestos packing rubs against the main shaft 20, increasing the gap and weakening the sealing effect. Furthermore, since the main shaft 20 is a rotating component and the sealing seat is a stationary component, the sealing effect of the comb teeth is highly dependent on the surface precision of the main shaft 20, making machining difficult. In addition, if radial displacement occurs during operation, the main shaft 20 may rub directly against the comb teeth, causing problems such as instantaneous failure.

[0026] See Figure 1-2 As shown, this embodiment provides a fan mechanical journal sealing device, including a housing 10, a main shaft 20, and a sealing assembly 30, wherein:

[0027] The housing 10 is a stationary component, and the main shaft 20 extends axially through the housing 10 and to the outside of the housing 10. The main shaft 20 can rotate relative to the housing 10.

[0028] The sealing assembly 30 includes a first housing 31 and a second housing 32, which are respectively mounted on the housing 10 and the main shaft 20. A preset gap exists between the first housing 31 and the second housing 32. The second housing 32 can rotate relative to the first housing 31 with the main shaft 20. Multiple protrusions 33 and recesses 34 are provided on opposite sides of the first housing 31 and the second housing 32, forming a fluid attenuation channel 35 through a fitting arrangement. The protrusions 33 and recesses 34 on the first housing 31 respectively mate with the recesses 34 and protrusions 33 on the second housing 32. In this embodiment, the first housing 31 is a stationary component connected to the housing 10, while the second housing 32 is rigidly connected to the main shaft 20 and serves as a rotating component along with the main shaft 20. The second housing 32 is tightly connected to the main shaft 20 without relative displacement, preventing radial runout of the main shaft 20 from causing friction with the second housing 32 and resulting in momentary failure. The gap between the rotating part and the stationary part is transferred from the spindle 20 and the stationary part to the first housing 31 and the second housing 32. The second housing 32 is equivalent to adding a sealing reference surface outside the spindle 20. The recess 34 and the protrusion 33 respectively provided on the first housing 31 and the second housing 32 can be precision machined separately, which reduces the stringent requirements on the machining accuracy of the spindle 20 and simplifies the machining and assembly difficulty.

[0029] The tortuous channel formed by the interlocking of the opposing protrusions 33 and concave portions 34 on the first housing 31 and the second housing 32 extends the airflow path, effectively preventing atmospheric air from seeping into the housing 10 and reducing system air leakage. Furthermore, the opposing concave portions 34 and protrusions 33 have a preset gap, and since they are not in contact, the gap will not widen due to long-term operation. It should be noted that during installation, the position of the high-temperature fan housing 10 after thermal expansion should be considered to avoid the preset gap being too small or causing friction. The size of the preset gap is not within the scope of the technical problem to be solved by this utility model, but those skilled in the art can make conventional designs based on thermal expansion, such as a gap of 0.5-1mm at room temperature and 0.2-0.5mm at high temperatures due to housing expansion; this is not limited here. In addition, the interlocking of the concave portions 34 and protrusions 33 on the first housing 31 and the second housing 32 also provides good guiding properties.

[0030] See Figure 2As shown, in one feasible embodiment, the second housing 32 has multiple annular grooves 320 on the side facing the first housing 31. A sealing sleeve 36 is provided within each groove 320, and the end of the sealing sleeve 36 facing away from the second housing 32 abuts against the surface of the first housing 31. The sealing sleeve 36, in conjunction with the fluid attenuation channel 35, forms a dual-protection structure combining throttling and blocking, effectively increasing the sealing effect. The sealing sleeve 36 and the first housing 31 fill the gap through elastic contact or tight fit, improving sealing reliability and compensating for errors in the preset gap. Compared to the instantaneous failure of traditional comb seals caused by direct friction from the radial displacement of the main shaft 20, the buffering effect of the sealing sleeve 36 significantly improves the anti-interference capability of the sealing device.

[0031] See Figure 1 As shown, in this embodiment, there are two grooves 320, which are respectively provided on two adjacent protrusions 33 of the second housing 32. The sealing level is increased by multiple sealing. In the existing design, once the comb teeth are worn, the gap between the comb teeth and the main shaft 20 increases and the sealing performance decreases. Only the sealing seat can be replaced, which is costly. However, in the embodiment provided in this application, the sealing sleeve 36 is a vulnerable part that bears the sealing pressure. Even if the sealing sleeve 36 is worn, the fluid attenuation channel 35 with the concave and convex fit can still maintain the sealing effect. Moreover, the sealing sleeve 36 can be replaced separately, making maintenance more convenient.

[0032] See Figure 2 As shown, further, the inner ring of the sealing sleeve 36 is provided with an elastic element 37 to limit the sealing sleeve 36 within the groove 320. An annular groove is formed on the side of the sealing sleeve 36 facing the first housing, and the elastic element 37 is disposed within this annular groove, pressing the sealing sleeve 36 tightly against the surface of the second housing 32 through elastic force. Because the elastic element 37 is elastic, the sealing sleeve 36 can adaptively adjust with changes in gap, always maintaining tight contact with the surface of the first housing 31. The elastic element 37 can be a spring or an annular rubber ring, etc.

[0033] See Figure 1-2 As shown, the first housing 31 and the second housing 32 are not in contact, so both ends of the fluid attenuation channel 35 are open. To prevent atmospheric gas from flowing directly into the channel from the end of the channel, in this embodiment, the end of the first housing 31 near the housing 10 radially at least partially covers the corresponding end of the second housing 32, and the end of the second housing 32 away from the housing 10 radially covers the corresponding end of the first housing 31. On the atmospheric side, the second housing 32 extends radially to the outer wall of the first housing 31 and covers the first housing 31, which can block atmospheric gas from directly entering the channel from the inlet of the fluid attenuation channel 35. On the housing 10 side, the first housing 31 extends radially and covers at least part of the second housing 32, so the first housing 31 and the second housing 32 can cover each other at both ends of the main shaft 20 to form a tight fit.

[0034] Further, see Figure 2 As shown, the second housing 32 has a circumferential extension 321 at the end opposite to the housing 10. The extension 321 protrudes from the outer wall of the first housing 31 and extends towards the housing 10. The extension 321 axially covers at least a portion of the first housing 31. When atmospheric gas enters the channel, it must first bypass the obstruction of the extension 321, thus weakening the initial gas momentum and increasing the path for entry into the gap. When the main shaft 20 rotates, the second housing 32 rotates synchronously with the main shaft 20. The extension 321 drives the surrounding gas to form a rotating airflow. The rotating airflow generates an outward centrifugal force, creating a reverse thrust on the gas attempting to enter, further hindering its approach to the channel inlet, and significantly improving the sealing capability against atmospheric gas.

[0035] See Figure 1-2 As shown, to facilitate the installation of this type of mechanical journal sealing device, in this embodiment, the first housing 31 is symmetrically divided into two halves along the axial direction. The first housing 31 is connected to the housing 10 by the first fastener 40. Since the housing 10 is relatively thin, to increase the stability of the connection between the first housing 31 and the housing 10, the first fastener 40 includes a flange. The flange has a split structure and is welded to the housing 10. The first housing 31 and the flange are fixed by bolts. The flange, the first housing 31, and the housing 10 are connected together as a stationary component and do not rotate with the main shaft 20.

[0036] See Figure 1 As shown, the second housing 32 is further divided into two halves symmetrically along the axial direction. The second housing 32 is connected to the main shaft 20 by a second fastener 41. The second fastener 41 is a bolt. Specifically, the two halves of the second housing 32 are fixed to the main shaft 20 by bolts, making the two a whole. The second housing 32 rotates with the main shaft 20.

[0037] The mechanical journal sealing device provided in this embodiment has better sealing performance than commonly used shaft end sealing devices, and more effectively solves the leakage problem at the shaft end of high-temperature fans.

[0038] The above description, based on the embodiments shown in the drawings, details the structure, features, and effects of this utility model. The above description is only a preferred embodiment of this utility model, but the scope of implementation of this utility model is not limited to what is shown in the drawings. Any changes made in accordance with the concept of this utility model, or modifications to equivalent embodiments, that do not exceed the spirit covered by the specification and drawings, shall be within the protection scope of this utility model.

Claims

1. A sealing device for a fan mechanical journal, characterized in that, include: chassis; The main shaft extends axially through the housing and outwards from the housing. The sealing assembly includes a first housing and a second housing, which are respectively mounted on the machine housing and the main shaft. There is a preset gap between the first housing and the second housing. The second housing can rotate relative to the first housing with the main shaft. The first housing and the second housing are provided with multiple protrusions and recesses on opposite sides along the axial direction. The protrusions and the recesses are fitted together to form a fluid attenuation channel.

2. The fan mechanical journal sealing device according to claim 1, characterized in that, The second housing has multiple annular grooves on the side facing the first housing, and a sealing sleeve is provided in the groove. The end of the sealing sleeve facing away from the second housing abuts against the surface of the first housing.

3. The fan mechanical journal sealing device according to claim 2, characterized in that, The inner ring of the sealing sleeve is provided with an elastic element to limit the sealing sleeve within the groove.

4. The fan mechanical journal sealing device according to claim 1, characterized in that, The end of the first housing near the casing radially at least partially covers the corresponding end of the second housing, and the end of the second housing away from the casing radially covers the corresponding end of the first housing.

5. The fan mechanical journal sealing device according to claim 1, characterized in that, The second housing has a circumferential extension at one end opposite to the first housing, the extension protruding from the outer wall of the first housing and extending toward one side of the first housing.

6. The fan mechanical journal sealing device according to claim 1, characterized in that, The first housing is symmetrically divided into two halves along the axial direction, and the first housing is connected to the machine housing by a first fastener.

7. The fan mechanical journal sealing device according to claim 6, characterized in that, The first fastener includes a flange, which has a split structure and is fixedly connected to the housing.

8. The fan mechanical journal sealing device according to claim 1, characterized in that, The second housing is symmetrically divided into two halves along the axial direction, and the second housing is connected to the main shaft by a second fastener.

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