Radial bearing and centrifugal pump thereof

Abstract

The utility model discloses a radial bearing and a centrifugal pump thereof, and relates to the technical field of bearing structure design. A pre-gap is reserved among the radial bearing, the bearing body and the shaft sleeve; pressurizing grooves are formed in the outer walls of the two ends of the bearing body; in the axis direction of the bearing body, the width of the pressurizing groove is gradually reduced in the extending direction from the end part of the bearing body to the middle part; in the axis direction of the bearing body, the pressurizing grooves are bent in the direction deviating from the rotating direction of the bearing body in the extending direction from the end of the bearing body to the middle. The centrifugal pump comprises the radial bearing. The defects that in the prior art, a hydrodynamic radial bearing is limited in bearing capacity and poor in flow guiding effect are overcome. According to the radial bearing and the centrifugal pump thereof, through the structural design of the pressurizing grooves, the flow guide effect on liquid is improved, through the pressurizing effect of the pressurizing grooves on the liquid, the stability of the liquid entering the pre-clearance is improved, stable flowing of the liquid is guaranteed, and the stability and the supporting force for supporting the shaft sleeve are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of bearing structure design, in particular to a radial bearing and a centrifugal pump thereof. Background Art

[0002] Centrifugal pumps have the characteristics of long working life, flat head curves, strong conveying capacity, etc., and are now widely used in industries such as aerospace, petrochemical, chemical fertilizer and pharmaceutical industries.

[0003] Most centrifugal pumps use rolling bearings or sliding bearings as the supporting bearings for the rotating shaft. However, rolling bearings or sliding bearings usually have the following defects: for example, failure due to continuous wear of the metal on the working surface, and there are problems such as lubricant aging and high-temperature dilution when using lubricants to lubricate the bearings.

[0004] Therefore, a new type of hydrodynamic bearing has begun to be used in centrifugal pumps. A hydrodynamic bearing is a non-contact sliding bearing that uses viscous liquid as a lubricant. The hydrodynamic bearing uses the liquid film pressure formed by the liquid in the wedge-shaped gap of the bearing when the rotating shaft rotates to support the load. Compared with rolling bearings and sliding bearings, hydrodynamic bearings have the advantages of smooth rotation, reliable operation, low noise, small vibration, small volume, and light weight. The hydrodynamic bearing uses the system working medium as a lubricant, so there is no need to consider the pollution of the lubricant to the system. Moreover, on the premise of fully ensuring the lubrication of the system working medium, the working surfaces of the bearings are separated by the system working medium and do not come into direct contact, which can greatly reduce surface wear.

[0005] Cavitation is likely to occur when the hydrodynamic bearing rotates at high speed. "Cavitation" refers to the phenomenon that the local pressure in the liquid medium is lower than the saturation pressure corresponding to the liquid temperature, resulting in the vaporization of the liquid. When the rotating shaft rotates, a high-pressure area and a low-pressure area will be formed in the cavity between the rotating shaft and the hydrodynamic bearing. And as the rotational speed of the rotating shaft gradually increases, the pressure in the low-pressure area decreases accordingly. When the liquid pressure in the low-pressure area in the cavity between the rotating shaft and the hydrodynamic bearing is lower than the saturation pressure corresponding to the incoming liquid, cavitation will occur in the cavity.

[0006] Due to the very small lubrication gap between the rotating shaft and the hydrodynamic bearing, the heat generated during the rotation of the rotating shaft also increases the temperature of the liquid film in the low-pressure area, and the corresponding liquid film saturation pressure value also rises accordingly, increasing the possibility of cavitation. When cavitation occurs in the liquid, part of the liquid changes into gas. Since the specific volume of the gas is much larger than that of the liquid, the gas quickly occupies most of the volume in the cavity, and the liquid film support force drops rapidly or even disappears, thus affecting the stability of the hydrodynamic bearing at high speeds and even causing failure in severe cases.

[0007] In the existing invention patent, the application number is: 201910095029.5, and the patent name is: A hydrodynamic radial bearing and a centrifugal pump; there are still the following defects:

[0008] 1. The blade structure design is unreasonable, and the guiding effect on the liquid is not good;

[0009] 2. Turbulence is likely to occur in the flow of the liquid during the drainage process, reducing the carrying stability of the entire bearing.

[0010] Therefore, in the prior art, the radial bearing has the defects of limited load-bearing capacity and poor guiding effect. Utility Model Content

[0011] In view of this, the main purpose of the present utility model is to provide a radial bearing and its centrifugal pump that improve the supporting effect on the shaft sleeve, ensure the smoothness of liquid flow, reduce the possibility of turbulence, and ensure the stability of the support for the shaft sleeve.

[0012] To achieve the above object, the technical solution of the present utility model is realized as follows:

[0013] A radial bearing, comprising: a bearing body and a shaft sleeve, and a pre-clearance is provided between the bearing body and the shaft sleeve;

[0014] In a preferred embodiment, pressure-increasing grooves are provided on the outer walls at both ends of the bearing body;

[0015] In a preferred embodiment, in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the width of the pressure-increasing groove gradually decreases;

[0016] In a preferred embodiment, in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the pressure-increasing groove bends away from the rotation direction of the bearing body.

[0017] In a preferred embodiment, a wedge-shaped cavity is provided on the entire circumference at the end of the outer wall of the bearing body.

[0018] In a preferred embodiment, a flow guiding groove is provided inside the wedge-shaped cavity, and one end of the flow guiding groove is conducted outside the bending arc of the pressure-increasing groove.

[0019] In a preferred embodiment, a plurality of flow guiding grooves are provided.

[0020] In a preferred embodiment, one end of each flow guiding groove away from the pressure-increasing groove is located at one end of the wedge-shaped cavity close to the middle of the bearing body.

[0021] In a preferred embodiment, one end of each of the diversion grooves away from the pressurization groove is on the same circumferential line of the bearing body.

[0022] In a preferred embodiment, tapered table surfaces are provided at both ends of the bearing body, and the tapered table surfaces and the wedge-shaped cavities are in smooth transition;

[0023] In a preferred embodiment, pressurization vanes are fixedly connected to the tapered table surfaces;

[0024] In a preferred embodiment, in the axial direction of the bearing body, the thickness of the pressurization vanes gradually increases in the direction from the end of the bearing body to the middle, and the distance between adjacent pressurization vanes gradually decreases.

[0025] In a preferred embodiment, both sides of the pressurization vane are respectively a flow-facing side and a flow-back side. In the axial direction of the bearing body, the flow-facing side is an arc surface and the flow-back side is a straight surface;

[0026] In a preferred embodiment, the pressurization vanes are integrally inclined, and the inclination direction of the pressurization vanes is the same as the rotation direction of the bearing body;

[0027] In a preferred embodiment, the upper side of the pressurization vane away from the tapered table surface is an arc surface;

[0028] In a preferred embodiment, the cross-sectional dimensions of the pressurization vane gradually decrease and are in smooth transition from the tapered table surface to the upper arc surface;

[0029] In a preferred embodiment, the upper side of the pressurization vane away from the tapered table surface is flush with the outer wall of the bearing body.

[0030] In a preferred embodiment, the pressurization vanes at both end faces of the bearing body are symmetrically arranged;

[0031] In a preferred embodiment, the pressurization vanes are evenly arranged;

[0032] In a preferred embodiment, the pressurization grooves are provided in the extending direction of the gaps between adjacent pressurization vanes.

[0033] A centrifugal pump includes the above-mentioned radial bearing.

[0034] The radial bearing and the centrifugal pump of the present utility model have the following beneficial effects:

[0035] The radial bearing includes: a bearing body and a bushing, and a pre-clearance is provided between the bearing body and the bushing; pressure-increasing grooves are formed on the outer walls at both ends of the bearing body; in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the width of the pressure-increasing groove gradually decreases; in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the pressure-increasing groove bends away from the rotation direction of the bearing body. The centrifugal pump includes the above-mentioned radial bearing.

[0036] It solves the defects that the hydrodynamic radial bearing in the prior art has limited load-carrying capacity and poor flow guiding effect.

[0037] The radial bearing and its centrifugal pump improve the flow guiding effect on the liquid through the structural design of the pressure-increasing groove, and through the pressure-increasing effect of the pressure-increasing groove on the liquid, improve the stability of the liquid entering the pre-clearance, ensure the stable flow of the liquid, and improve the smoothness and supporting force of the support for the bushing. Brief Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0039] Figure 1 It is a schematic structural diagram of a radial bearing according to an embodiment of the present disclosure;

[0040] Figure 2 It is a side view of a radial bearing according to an embodiment of the present disclosure;

[0041] Figure 3 It is a schematic structural diagram of the bearing body of a radial bearing according to an embodiment of the present disclosure.

[0042]

Main Component Symbol Description

[0043] 1. Bearing body; 2. Bushing; 3. Tapered table surface;

[0044] 4. Pressure-increasing vane;

[0045] 41. Flow-facing side; 42. Flow-back side;

[0046] 5. Pressure-increasing groove;

[0047] 6. Flow-guiding groove. Detailed Embodiment

[0048] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments of the present utility model with respect to its radial bearing and centrifugal pump.

[0049] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0050] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless otherwise clearly specified in the context, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0051] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0052] For the sake of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above" etc. can be used here to describe the spatial positional relationship between a device or feature shown in the figure and other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the figure. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned as "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientation of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations will be made for the spatial relative descriptions used here.

[0053] As Figures 1-3 shown, the radial bearing includes: a bearing body 1 and a bushing 2, and a pre-clearance is provided between the bearing body 1 and the bushing 2;

[0054] To increase the pressure of the hydrodynamic oil film, pressure-increasing grooves 5 are provided on the outer walls at both ends of the bearing body 1; the liquid is introduced into the pre-clearance through the pressure-increasing grooves 5, increasing the flow rate of the liquid entering the pre-clearance, enhancing the pressure-increasing effect, and ensuring the stable supporting effect on the bushing 2.

[0055] To ensure that during the liquid diversion process, under the centrifugal action on the liquid, the pressure on the liquid is increased, the pressure-bearing capacity of the liquid is ensured, and the supporting effect on the bushing is improved. In the axial direction of the bearing body 1, in the direction extending from the end of the bearing body 1 towards the middle, the width of the pressure-increasing groove 5 gradually decreases; the depth of the pressure-increasing groove 5 also gradually decreases, and even the bottom of the pressure-increasing groove 5 smoothly transitions to the surface of the bearing body 1.

[0056] To improve the adaptation to the centrifugal action effect and ensure a better pressure-increasing effect on the liquid during the centrifugal working process. In the axial direction of the bearing body 1, in the direction extending from the end of the bearing body 1 towards the middle, the pressure-increasing groove 5 bends away from the rotation direction of the bearing body 1.

[0057] To increase the amount of liquid entering between the bearing body 1 and the bushing 2 at the initial stage and improve the supporting effect on the bushing. A wedge-shaped cavity is provided on the entire circumference at the end of the outer wall of the bearing body 1. Through the guiding action of the wedge-shaped cavity, the amount of liquid entering is increased to ensure the supporting effect.

[0058] To ensure that the liquid in the diversion groove 6 smoothly flows into the pre-clearance and improve the smooth entry of the liquid into the pre-clearance. A diversion groove 6 is provided inside the wedge-shaped cavity, and one end of the diversion groove 6 is conducted outside the curved arc of the pressure-increasing groove 5.

[0059] To improve the diversion effect, multiple diversion grooves 6 are provided.

[0060] To improve the diversion effect and ensure the smooth diversion of the liquid towards the middle of the bearing body 1. One end of each diversion groove 6 away from the pressure-increasing groove 5 is located at one end of the wedge-shaped cavity close to the middle of the bearing body 1.

[0061] To ensure the bearing capacity of the bearing body 1 and ensure that a pre-clearance can be smoothly formed in the part of the bearing body 1 except for the wedge-shaped cavity, ensuring the load-bearing capacity of the hydrodynamic oil film of the liquid. One end of each diversion groove away from the pressure-increasing groove is located on the same circumferential line of the bearing body 1.

[0062] Conical platforms 3 are provided at both ends of the bearing body 1, and the conical platforms 3 are smoothly transitioned with the wedge-shaped cavity;

[0063] To increase the pressure of the hydrodynamic oil film, pressure-increasing vanes 4 are fixedly connected to the conical platforms 3; the diverted liquid enters the inside of the pre-clearance.

[0064] In order to improve the diversion effect of the liquid, the liquid is compressed at the pressurizing blade 4 to increase the pressure of the liquid entering the pre-gap and improve the load-bearing capacity of the hydrodynamic oil film. In the axial direction of the bearing body 1, the thickness of the pressurizing blade 4 gradually increases in the extending direction from the end of the bearing body 1 to the middle, and the distance between adjacent pressurizing blades 4 gradually decreases.

[0065] During the long-term use process, since the pressure of the liquid becomes greater and greater as the pressurizing blade 4 extends from the end of the bearing body 1 to the middle, the load-bearing capacity of the pressurizing blade needs to gradually increase. In the prior art, the thicknesses of the pressurizing blades 4 are the same. During the long-term use process, the pressurizing blades near the middle of the bearing body 1 are prone to damage, seriously affecting the service life of the entire product. By increasing the thickness of the pressurizing blade 4, it is ensured that during the process of the liquid gradually entering the pre-gap, the pressure-bearing capacity of the pressurizing blade is ensured, the service life of the pressurizing blade is ensured, and the defect of damage to the pressurizing blade during the long-term use process is avoided.

[0066] In order to improve the diversion effect, ensure that the liquid does not exhibit turbulence, and gradually increase the pressure of the liquid to ensure the effect of the hydrodynamic oil film. The two sides of the pressurizing blade 4 are respectively: the flow-receiving side 41 on the front side of the rotation of the bearing body 1 and the backflow side 42 on the rear side of the rotation of the bearing body 1. In the axial direction of the bearing body 1, the flow-receiving side 41 is an arc surface, which has a better diversion effect. The backflow side 42 is a straight surface, which stabilizes the flow direction of the liquid and reduces the possibility of turbulence. In the axial direction, one side is an arc and the other side is a straight surface, and the entire thickness increases uniformly. Moreover, the distance between adjacent pressurizing blades 4 gradually decreases, improving the pressurization effect on the liquid. It is ensured that during the process of the liquid entering the reserved gap, the volume gradually decreases uniformly and the pressure gradually increases, ensuring the stability of pressurization and improving the pressurization effect.

[0067] In order to improve the pressurization effect of the entire pressurizing blade 4, reduce the effect of the liquid on the bushing 2 when initially entering the bearing body 1, ensure a greater supporting effect on the bushing 2 after the liquid pressurization is stable, and improve the stability of the support for the bushing 2. The entire pressurizing blade 4 is inclined, and the inclination direction of the pressurizing blade 4 is the same as the rotation direction of the bearing body 1. That is: the upper end of the pressurizing blade 4 inclines towards the flow-receiving side 41. During the initial action of the pressurizing blade 4 on the liquid, it mainly drives the liquid to flow towards the middle of the bearing body 1 through the pressurizing blade 4, reducing the effect of the liquid on the bushing 2.

[0068] In order to improve the smoothing effect and ensure that the liquid overflows smoothly. The upper side of the pressurizing blade 4 away from the conical table 3 is an arc surface.

[0069] In order to improve the pressure-bearing effect of the booster vane 4, the pressure on one end of the booster vane 4 close to the bushing 2 can be relatively small, and a larger space for drainage can be provided. The cross-sectional dimensions of the booster vane 4 gradually decrease and smoothly transition from the conical table surface 3 to the upper arc surface. By increasing the opening size of the booster vane 4 at the end of the bearing body 1, the flow rate of the liquid entering the bearing body 1 can be maximized. At the same time, the pressure-bearing strength of the booster vane 4 can be ensured, and the boosting effect of the booster vane 4 can be improved.

[0070] In order to maximize the drainage, reduce the overflow of the liquid, and ensure the boosting effect. The upper side of the booster vane 4 away from the conical table surface 3 is flush with the outer wall of the bearing body 1. To a certain extent, the supporting effect on the bushing 2 is also improved, ensuring the supporting stability of the bushing.

[0071] Of course, in order to provide a balanced supporting effect on both ends of the bushing 2 and improve the stability of the bushing 2. The booster vanes 4 on both end faces of the bearing body 1 are symmetrically arranged.

[0072] In order to ensure that the bearing body 1 can rotate smoothly during self-rotation. The booster vanes 4 are evenly arranged.

[0073] In order to further improve the boosting effect and ensure smooth flow of the liquid during the entry into the pre-clearance. It further includes: a boosting groove 5, which is opened at both ends of the outer wall of the bearing body 1 close to the conical table surface 3. Through the boosting groove 5 for re-diversion and boosting, it is ensured that the pressure of the liquid entering the pre-clearance is close to the pressure of the liquid in the reserved clearance, and the excess liquid can overflow smoothly.

[0074] In order to cooperate with the booster vane 4 for diversion, ensure the smooth flow of the liquid, improve the diversion effect, and thus increase the boosting effect of the liquid. The boosting groove 5 is opened in the extending direction of the gap between adjacent booster vanes 4.

[0075] This centrifugal pump includes the above-mentioned radial bearing.

[0076] The above is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. A radial bearing, characterized in that, Comprising: A bearing body (1) and a bushing (2), with a pre-clearance left between the bearing body (1) and the bushing (2); Pressurizing grooves (5) are formed on the outer walls at both ends of the bearing body (1); In the axial direction of the bearing body (1), in the extending direction from the end of the bearing body (1) towards the middle, the width of the pressurizing groove (5) gradually decreases; In the axial direction of the bearing body (1), in the extending direction from the end of the bearing body (1) towards the middle, the pressurizing groove (5) bends away from the rotation direction of the bearing body (1).

2. The radial bearing according to claim 1, characterized in that, A wedge-shaped cavity is formed in the entire circumference at the end of the outer wall of the bearing body (1).

3. The radial bearing according to claim 2, characterized in that, A flow guiding groove (6) is formed inside the wedge-shaped cavity, and one end of the flow guiding groove (6) is communicated with the outside of the bending arc of the pressurizing groove (5).

4. The radial bearing according to claim 3, wherein, A plurality of the flow guiding grooves (6) are formed.

5. The radial bearing according to claim 4, characterized in that, One end of each flow guiding groove (6) away from the pressurizing groove (5) is located at one end of the wedge-shaped cavity close to the middle of the bearing body (1).

6. The radial bearing according to claim 4, wherein One end of each flow guiding groove away from the pressurizing groove is located on the same circumferential line of the bearing body (1).

7. The radial bearing according to claim 2, characterized in that, Conical surfaces (3) are formed at both ends of the bearing body (1), and the conical surfaces (3) are smoothly transitioned with the wedge-shaped cavity; Pressurizing vanes (4) are fixedly connected to the conical surfaces (3); In the axial direction of the bearing body (1), in the extending direction from the end of the bearing body (1) towards the middle, the thickness of the pressurizing vane (4) gradually increases, and the distance between adjacent pressurizing vanes (4) gradually decreases.

8. The radial bearing according to claim 7, characterized in that, Both sides of the pressurizing vane (4) are respectively: a flow-facing side (41) and a flow-back side (42), in the axial direction of the bearing body (1), the flow-facing side (41) is an arc surface, and the flow-back side (42) is a straight surface; The pressurizing vane (4) is integrally inclined, and the inclination direction of the pressurizing vane (4) is the same as the rotation direction of the bearing body (1); The upper side of the pressurizing vane (4) away from the conical surface is an arc surface; The cross-sectional dimension of the pressurizing vane (4) from the conical surface (3) to the upper arc surface gradually decreases and is smoothly transitioned; The upper side of the pressurizing vane (4) away from the conical surface (3) is flush with the outer wall of the bearing body (1).

9. The radial bearing according to claim 8, characterized in that, The pressurizing vanes (4) on both end faces of the bearing body (1) are symmetrically arranged; The pressurizing vanes (4) are evenly arranged; The pressurizing groove (5) is formed in the extending direction of the gap between adjacent pressurizing vanes (4).

10. A centrifugal pump, characterized in that, Comprising the radial bearing according to any one of claims 1-9.

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