Cooling device and bearing housing

Abstract

The application belongs to the technical field of bearing boxes, and discloses a cooling device and a bearing box. The cooling device comprises an axial flow fan and a throttle net, both of which are connected to the bearing end cover of the bearing box through a connecting shaft, and the throttle net is located between the axial flow fan and the bearing end cover. A plurality of through holes are arranged on the central position of the axial flow fan and the throttle net, so as to form positive pressure in the axial flow fan during rotation. The axial flow fan can generate axial high-speed air flow, and a plurality of through holes are arranged on the axial flow fan and the throttle net, which can ensure the flow of high-speed air flow between the through holes, effectively balance the internal air pressure of the axial flow fan, further increase the pressure, and reduce the wind speed, so as to ensure the cooling effect, form positive pressure in the axial flow fan, avoid the problem of outflow of cooled lubricating oil in a negative pressure environment, and fundamentally solve the problem of lubricating oil leakage of the bearing box.

Description

Technical Field

[0001] This invention relates to the field of bearing housing technology, and more particularly to a cooling device and a bearing housing. Background Technology

[0002] Currently, all 43 high-power oil pumps in a domestically manufactured oil pipeline exhibit varying degrees of lubricant leakage. Most of the leakage occurs along the outside of the bearing isolators, causing not only a messy and difficult-to-clean equipment site but also posing a risk of insufficient lubrication in the bearing housings and potential safety hazards. Typically, these oil pumps are single-stage, double-suction, split-section centrifugal pumps, and the bearings are mostly sliding bearings. Furthermore, the thrust bearing is often located on the non-drive end and consists of two back-to-back thrust ball bearings forming a thrust bearing assembly, lubricated using oil slinger rings. The bearing housings are also mostly air-cooled using coaxial centrifugal fans and sealed with labyrinth bearing isolators.

[0003] As attached Figure 8 As shown, the labyrinth bearing isolator is a labyrinth oil seal that incorporates dynamic sealing theory. It not only dynamically balances the pressure inside and outside the cavity during shaft operation but also provides spatial isolation, preventing lubricant leakage and the entry of external contaminants. Furthermore, both the dynamic and static rings are sealed with O-rings, and the only channel through which external contaminants can enter the cavity is the small gap between the dynamic and static rings—the channel through which lubricant leakage has been observed.

[0004] Despite continuous testing and optimization of the bearing isolator in recent years, the lubricating oil leakage problem remains unresolved. During testing, it was found that oil leakage typically does not occur within the first two hours of startup, but begins after two hours. This initially suggests that the leakage occurs after the lubricating oil temperature rises to the operating temperature of approximately 65°C, forming an oil mist. To investigate whether the cooling fan affects the oil leakage, the fan was removed during winter and subjected to long-term testing, which revealed no leakage. Further analysis of the centrifugal fan's flow field pressure distribution, combined with... Figure 9 and attached Figure 13 As shown, when using the centrifugal fan 100, the high-speed airflow it generates will encounter the protective cover and change direction, blowing out radially. According to Bernoulli's principle, a negative pressure will be formed between the centrifugal fan 100 and the bearing housing end cover 300, and the pressure can reach -300 Pa. This indicates that the leaked lubricating oil is formed as oil mist after cooling, and the external suction force generated by the centrifugal fan is the root cause of the bearing isolator leakage failure. Therefore, ensuring that the bearing housing is cooled while preventing the generation of external suction force on the outside of the bearing isolator is currently the fundamental solution for solving the leakage problem in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a cooling device and a bearing housing to ensure that no external suction force is generated outside the bearing isolator while the bearing housing is cooled, thereby fundamentally solving the problem of lubricating oil leakage in the bearing housing under negative pressure after cooling.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A cooling device, disposed in the bearing housing, comprising:

[0008] An axial fan and a throttling screen are both connected to the bearing end cover of the bearing housing via a connecting shaft. The throttling screen is located between the axial fan and the bearing end cover. Several through holes are provided at the center of the axial fan and on the throttling screen. Positive pressure can be generated inside the axial fan when it rotates.

[0009] Optionally, the axial fan includes a fan body and blades, with a plurality of blades spaced apart on the fan body, and the connecting shaft passing through the fan body.

[0010] Alternatively, several of the blades are distributed at equal intervals on the fan body with the center of the axial fan as the axis.

[0011] Alternatively, the blade is disposed perpendicular to the surface of the fan body, and the extension line of each blade along its length does not pass through the center of the axial fan.

[0012] Optionally, a connecting hole is provided through the center of the fan body for connecting the connecting shaft.

[0013] Optionally, the fan body is provided with a plurality of first through holes, and the plurality of first through holes are equally spaced around the axis of the connecting hole on the outer side of the connecting hole.

[0014] Optionally, the axial fan may further include a support base, which protrudes from the side of the fan body away from the blades, and the connection hole extends through the support base.

[0015] Optionally, the throttling net is provided with a clearance opening, through which the connecting shaft passes.

[0016] Optionally, a plurality of second through holes are provided through the throttling network, and an array of the plurality of second through holes is distributed on the outside of the clearance opening.

[0017] A bearing housing, comprising any cooling device, a connecting shaft, a bearing end cover, and a bearing isolator, wherein the fan body in the cooling device and the bearing isolator are both connected to the connecting shaft, and the throttling screen in the cooling device and the bearing end cover are both located outside the bearing isolator, and positive pressure can be generated at the bearing isolator when the fan body rotates.

[0018] The beneficial effects of this invention are:

[0019] This invention employs an axial flow fan to generate a high-speed axial airflow. Several through holes are located at the center of the axial flow fan, and several more through holes are also present on the throttling mesh between the axial flow fan and the bearing end cover. This ensures that the high-speed airflow flows between the through holes and effectively balances the internal air pressure of the axial flow fan, further increasing the pressure and reducing the wind speed. This ensures sufficient cooling air to cool the bearing housing. Furthermore, it creates positive pressure inside the axial flow fan, preventing the generation of negative pressure outside the bearing end cover, which would otherwise cause the cooled lubricating oil to leak out under negative pressure. This fundamentally solves the problem of lubricating oil leakage from the bearing housing. Attached Figure Description

[0020] Figure 1 This is a first isometric view of the axial fan in the cooling device described in this embodiment of the invention;

[0021] Figure 2 This is a second isometric view of the axial fan in the cooling device described in this embodiment of the invention;

[0022] Figure 3 This is a front view schematic diagram of the axial fan in the cooling device described in the embodiment of the present invention;

[0023] Figure 4 This is a rear view schematic diagram of the axial fan in the cooling device described in the embodiment of the present invention;

[0024] Figure 5 This is an isometric view of the throttling mesh in the cooling device described in the embodiment of the present invention;

[0025] Figure 6 This is a front view schematic diagram of the throttling mesh in the cooling device described in an embodiment of the present invention;

[0026] Figure 7 This is a partial cross-sectional view of the cooling device described in an embodiment of the present invention when it is installed in the bearing housing;

[0027] Figure 8 This is a partial cross-sectional schematic diagram of a bearing housing equipped with a centrifugal fan in the prior art;

[0028] Figure 9 This describes the flow field distribution of centrifugal fans in existing technologies.

[0029] Figure 10 This describes the pressure distribution of the axial fan in the cooling device described in this embodiment of the invention.

[0030] Figure 11 This describes the pressure distribution of the axial fan and throttling mesh in the cooling device described in this embodiment of the invention.

[0031] Figure 12 This describes the cooling air velocity field of the axial fan in the cooling device described in this embodiment of the invention.

[0032] Figure 13 This describes the cooling air velocity field of a centrifugal fan in existing technology.

[0033] In the picture:

[0034] 10-Axial fan; 20-Throttling screen; 100-Centrifugal fan; 200-Connecting shaft; 300-Bearing end cover; 400-Bearing isolator; 11-Fan body; 12-Blade; 13-Support base; 101-Connecting hole; 102-First through hole; 103-Annular space; 201-Allowing opening; 202-Second through hole; 203-Fixing hole. Detailed Implementation

[0035] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0036] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0038] The technical solution of this embodiment will be further described below with reference to the accompanying drawings and specific implementation methods.

[0039] like Figures 1-13 As shown, this embodiment provides a cooling device disposed in a bearing housing. The cooling device includes an axial fan 10 and a throttling screen 20, both of which are connected to the bearing end cover 300 of the bearing housing via a connecting shaft 200. The throttling screen 20 is located between the axial fan 10 and the bearing end cover 300. Several through holes are provided at the center of the axial fan 10 and on the throttling screen 20. When the axial fan 10 rotates, positive pressure can be formed inside it.

[0040] On the other hand, the bearing housing includes a cooling device, a connecting shaft 200, a bearing end cover 300, and a bearing isolator 400. The fan body 11 in the cooling device and the bearing isolator 400 are both connected to the connecting shaft 200, and the throttling screen 20 in the cooling device and the bearing end cover 300 are both located outside the bearing isolator 400. When the fan body 11 rotates, positive pressure can be generated at the bearing isolator 400.

[0041] Specifically, in this embodiment, an axial fan 10 is used to generate a high-speed axial airflow. Several through holes are provided at the center of the axial fan 10, and several through holes are also provided on the throttling mesh 20 located between the axial fan 10 and the bearing end cover 300. This ensures that the high-speed airflow flows between the through holes and effectively balances the internal air pressure of the axial fan 10, thereby increasing the pressure and reducing the wind speed. This ensures that sufficient cooling air can cool the bearing housing. It also creates positive pressure inside the axial fan 10, preventing the generation of suction force on the outside of the bearing end cover 300 to create negative pressure, which would cause the cooled lubricating oil to flow out under negative pressure, thus fundamentally solving the problem of lubricating oil leakage from the bearing housing.

[0042] The specific structure of the cooling device in this embodiment will be described below.

[0043] like Figures 1-6As shown, in this embodiment, the cooling device includes an axial fan 10 and a throttling screen 20, both of which are connected to the bearing end cover 300 in the bearing housing via a connecting shaft 200, thereby fixing the cooling device in the bearing housing. Furthermore, the throttling screen 20 is located between the axial fan 10 and the bearing end cover 300, and both the axial fan 10 and the throttling screen 20 are provided with several through holes. This allows positive pressure to be generated inside the axial fan 10 while reducing the wind speed, and also ensures sufficient cooling air enters the bearing housing due to the through holes. This avoids the problem in the prior art where a centrifugal fan generates high-speed airflow that changes direction and blows outward, creating negative pressure, thereby solving the problem of oil mist leakage in the bearing housing under negative pressure conditions.

[0044] like Figures 1-4 As shown, optionally, in this embodiment, the axial fan 10 includes a fan body 11, blades 12, and a support base 13, and is provided with a connecting hole 101, a first through hole 102, and an annular space 103. Specifically, in this embodiment, the fan body 11 includes a flat portion and an arc-shaped portion. Exemplarily, the arc-shaped portion is configured as a cylindrical structure, and the diameter of the side of the arc-shaped portion connecting to the flat portion is smaller than the diameter of the opening on the other side of the arc-shaped portion. Specifically, the support base 13 is disposed inside the arc-shaped portion and vertically disposed at the center position of the flat portion, thereby forming an annular space 103 by surrounding the outer side of the support base 13 and the inner side of the arc-shaped portion, so as to deliver a high-speed airflow in the annular space 103 when the axial fan 10 rotates, forming positive pressure.

[0045] Furthermore, the inner diameter of the arcuate portion in the fan body 11 gradually increases along the direction away from the flat portion, thereby making the outer surface of the fan body 11 arcuate. Specifically, a plurality of blades 12 are spaced apart on the outer side of the arcuate portion of the fan body 11, and each blade 12 is perpendicular to the outer side of the arcuate surface of the arcuate portion in the fan body 11. Furthermore, the extension line of each blade 12 along its length direction does not pass through the center of the axial flow fan 10, nor does it intersect with the axis of the flat portion in the axial flow fan 10. Specifically, in this embodiment, the extension line of each blade 12 along its length direction is tangent to the outer diameter of the flat portion, and the bottom of the blade 12 is in contact with the arcuate surface of the arcuate portion, so that when the fan body 11 rotates, the blades 12 can rotate in a spiral manner, achieving the effect of axial high-speed airflow. Specifically, a plurality of blades 12 are equally spaced on the fan body 11 with the center of the axial flow fan 10 as the axis to ensure the stable generation of axial airflow direction. For example, the outer ends of all blades 12, i.e. the ends near the larger diameter of the arc-shaped portion, can be formed into an outer circle, and their inner ends, i.e. the ends near the flat portion, can be formed into an inner circle. The outer and inner circles are coaxial circles, and their axes are on the same straight line as the axis of the fan body 11, so as to ensure that the high-speed airflow can be generated continuously and uniformly along the axial direction.

[0046] Specifically, a connecting hole 101 is provided through the center of the flat portion of the fan body 11 for connecting the shaft 200. Optionally, a keyway is provided in the connecting hole 101, so that the connecting shaft 200 can be locked to the fan body 11 by the cooperation of the key and the keyway. Optionally, a support base 13 protrudes from the side of the flat portion of the fan body 11 away from the blades 12, and the connecting hole 101 and the keyway are provided through the support base 13. Thus, the mechanical strength of the connection between the fan body 11 and the connecting shaft 200 can be effectively improved by the support base 13, preventing them from falling off during rotation.

[0047] Furthermore, a plurality of first through holes 102 are provided through the fan body 11, and the plurality of first through holes 102 are equally spaced on the outer circumferential side of the connecting hole 101 with the axis of the connecting hole 101 as the axis. In this embodiment, the plurality of first through holes 102 are all provided on the planar part and are all connected to the annular space 103. Thus, when an axial high-speed airflow is generated, the first through holes 102 can ensure the smooth flow of the high-speed airflow, balance the internal wind pressure of the axial fan 10, avoid excessive wind pressure, and thus achieve a micro positive pressure effect inside the axial fan 10.

[0048] like Figure 5 and Figure 6 As shown, in this embodiment, the throttling mesh 20 is provided with a clearance opening 201, a second through hole 202, and a fixing hole 203. Optionally, the connecting shaft 200 passes through the clearance opening 201, so that it can be connected to the fan body 11 after passing through. Exemplarily, in this embodiment, the clearance opening 201 has a cross-shaped structure with rounded corners, and fixing holes 203 are provided through the four corners, so that the throttling mesh 20 can be fixed to the bearing end cover 300 or the protective cover through the fixing holes 203. Further, the throttling mesh 20 is provided with a plurality of second through holes 202, and the plurality of second through holes 202 are arrayed on the outside of the clearance opening 201, so as to ensure the smooth delivery of axial high-speed airflow. Figure 7 As shown, when the axial fan 10 rotates, the high-speed airflow that is far from its axis can be axially transported through the second through hole 202 to ensure the cooling effect, and the high-speed airflow that is close to its axis can directly enter the bearing housing through the clearance port 201 to ensure the positive pressure effect.

[0049] The specific structure of the bearing housing in this embodiment will be described below.

[0050] The bearing housing includes the aforementioned cooling device, connecting shaft 200, bearing end cover 300, and bearing isolator 400. Specifically, the bearing isolator 400 and the fan body 11 in the cooling device are both sleeved on the outside of the connecting shaft 200, and the bearing end cover 300 and the throttling screen 20 in the cooling device are both sleeved on the bearing isolator 400. Thus, under the action of the bearing isolator 400, a rotational connection can be achieved between the connecting shaft 200, the throttling screen 20, and the bearing end cover 300. Therefore, when the connecting shaft 200 drives the fan body 11 to rotate, the positions of the throttling screen 20 and the bearing end cover 300 will not change. Furthermore, a protective cover can be installed in the bearing housing, sleeved on the outside of the bearing isolator 400 and mounted on the throttling screen 20, to provide protection. Alternatively, an outer cover can be provided, surrounding the outside of the cooling device to ensure concentrated delivery of high-speed airflow, prevent diffusion, and guarantee cooling effect. Therefore, when the fan body 11 rotates in the cooling device, the arrangement of its blades 12 can generate a high-speed axial airflow. With the arrangement of the first through hole 102 and the avoidance port 201 and the second through hole 202 in the throttling mesh 20, the high-speed axial airflow can be delivered from the outer end of the axial fan 10 to the outside of the bearing end cover 300, and from the inner end to the bearing isolator 400, thereby creating a positive pressure effect and preventing leakage of oil mist in the bearing isolator 400 after cooling.

[0051] Combination Figures 9-13 A comparison of data analysis with existing centrifugal fans 100 shows that when the centrifugal fan 100 is replaced with the axial fan 10 and throttling mesh 20 in this embodiment for smooth simulation calculations, the air velocity is significantly reduced. Furthermore, the first through-hole 102 in the axial fan 10 further balances the internal air pressure, preventing excessive air pressure from causing other effects on the bearing housing. For example, when using the centrifugal fan 100, the pressure outside the bearing isolator 400 can reach -300 Pa. Correspondingly, after replacing it with the combination of the axial fan 10 and throttling mesh 20, the pressure outside the bearing isolator 400 can be increased to -60 Pa, demonstrating a significant pressure boost. Therefore, the throttling mesh 20 further reduces the wind speed and increases the central air pressure of the axial fan 10, achieving a positive pressure effect at the bearing isolator 400 and fundamentally solving the negative pressure oil leakage problem when using the centrifugal fan 100 in the prior art. Specifically, after testing four identical pumps, each equipped with a cooling device in this embodiment, for over 8,000 hours, no leakage was found. This was further demonstrated by the successful application of six pumps, which also showed no leakage issues. This indicates that the cooling device structure in this embodiment effectively solves the oil leakage problem.

[0052] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A cooling device, disposed in a bearing housing, characterized in that, The cooling device includes: An axial fan (10) and a throttling mesh (20) are both connected to the bearing end cover (300) of the bearing housing via a connecting shaft (200). The throttling mesh (20) is located between the axial fan (10) and the bearing end cover (300). Several through holes are provided at the center of the axial fan (10) and on the throttling mesh (20). When the axial fan (10) rotates, positive pressure can be formed inside it.

2. The cooling device according to claim 1, characterized in that, The axial fan (10) includes a fan body (11) and blades (12), with a plurality of blades (12) spaced apart on the fan body (11), and the connecting shaft (200) passing through the fan body (11).

3. The cooling device according to claim 2, characterized in that, Several blades (12) are evenly distributed on the fan body (11) with the center of the axial fan (10) as the axis.

4. The cooling device according to claim 3, characterized in that, The blades (12) are arranged perpendicular to the surface of the fan body (11), and the extension line of each blade (12) along its length direction does not pass through the center of the axial fan (10).

5. The cooling device according to claim 2, characterized in that, A connecting hole (101) is provided through the center of the fan body (11) for connecting the connecting shaft (200).

6. The cooling device according to claim 5, characterized in that, The fan body (11) has a plurality of first through holes (102) through it. The plurality of first through holes (102) are evenly distributed around the axis of the connecting hole (101) on the outer side of the circumference of the connecting hole (101).

7. The cooling device according to claim 5, characterized in that, The axial fan (10) also includes a support base (13), which protrudes from the side of the fan body (11) away from the blades (12), and the connection hole (101) is provided through the support base (13).

8. The cooling device according to claim 1, characterized in that, The throttling net (20) is provided with a clearance opening (201), and the connecting shaft (200) passes through the clearance opening (201).

9. The cooling device according to claim 8, characterized in that, The throttling mesh (20) is provided with a plurality of second through holes (202), and the plurality of second through holes (202) are arrayed on the outside of the clearance opening (201).

10. A bearing housing, characterized in that, The device includes a cooling device as described in any one of claims 1-9, a connecting shaft (200), a bearing end cover (300), and a bearing isolator (400). The fan body (11) in the cooling device and the bearing isolator (400) are both connected to the connecting shaft (200), and the throttling screen (20) in the cooling device and the bearing end cover (300) are both located outside the bearing isolator (400). When the fan body (11) rotates, it can generate positive pressure at the bearing isolator (400).

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