Floating type throat bushing for improving pressure of sealing cavity

Abstract

The utility model discloses a floating type throat bushing for improving the pressure of a sealing cavity, and relates to the technical field of mechanical sealing of centrifugal pumps, in particular to the floating type throat bushing which is applied to the oil refining and petrochemical industry and is used for improving the pressure of the sealing cavity. A shaft and an impeller assembled on the shaft are arranged in a pump cover; the throat bushing is installed in the pump cover in a floating mode. A positioning pin is installed on the throat lining, and the positioning pin and a semicircular notch formed in the pump cover play a role in preventing rotation of the throat lining. And the diameter of the positioning pin is 5mm. A wave spring is assembled at the tail end of the sealing cavity to pre-tighten the throat lining. And a positioning ring is fixedly arranged in a groove of the sealing cavity to fix the wave spring. According to the technical scheme, the problems that in the prior art, a fixed throat lining structure is relatively large in gap, and the leakage rate of a sealing cavity is large are solved; under the working condition of a medium easy to vaporize, the medium is vaporized on the surface of the sealing surface, so that the sealing surface is in lubrication failure, sealing failure is caused, and normal operation of the pump is influenced.

Description

Technical Field

[0001] This utility model relates to the field of centrifugal pump mechanical seal technology, specifically a floating throat bushing for increasing the pressure of a sealing cavity in the oil refining and petrochemical industries. Background Technology

[0002] Existing single-stage cantilever centrifugal pumps use a fixed throat bushing structure for their mechanical seals; however, the fixed throat bushing structure has a relatively large clearance, resulting in significant leakage in the sealing cavity. When encountering easily vaporized media, the media vaporizes on the sealing surface, leading to lubrication failure and ultimately seal failure, thus affecting the normal operation of the pump.

[0003] In view of the problems existing in the prior art, it is necessary to study and design a new type of floating throat bushing for increasing the pressure of the sealing cavity, so as to overcome the problems existing in the prior art. Utility Model Content

[0004] The existing fixed throat bushing structure suffers from relatively large clearances and significant leakage in the sealing cavity. Furthermore, in applications involving easily vaporized media, vaporization on the sealing surface leads to lubrication failure, resulting in seal failure and impacting pump operation. This invention addresses these issues by providing a floating throat bushing to increase the pressure in the sealing cavity. The fixed throat bushing is replaced by a floating one, secured by a locating pin, wave spring, and locating ring. This allows the throat bushing to float during mechanical operation, effectively isolating the sealing cavity and providing a higher vaporization pressure margin.

[0005] The technical means adopted in this utility model are as follows:

[0006] A floating throat bushing for increasing the pressure of a sealing cavity includes a pump cover; a shaft is disposed inside the pump cover, and an impeller is mounted on the shaft; a fixed throat bushing is disposed inside the pump cover to isolate the sealing cavity.

[0007] Furthermore, the throat bushing was changed from a fixed installation method to a floating installation method;

[0008] Furthermore, the throat bushing is floatingly installed in the pump cover.

[0009] Furthermore, a locating pin is installed on the throat bushing, and the locating pin and the semi-circular notch on the pump cover play a role in preventing the throat bushing from rotating.

[0010] Furthermore, the diameter of the locating pin is 5mm.

[0011] Furthermore, a wave spring is installed at the end of the sealing cavity to pre-tighten the throat bushing.

[0012] Furthermore, a positioning ring is fixedly installed in the groove of the sealing cavity to fix the wave spring.

[0013] Furthermore, the throat bushing is made to float during mechanical operation, effectively isolating the sealing cavity to meet a higher vaporization pressure margin.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] The floating throat bushing provided by this utility model is used to increase the pressure of the sealing cavity. The floating throat bushing improves the stability and life of the single-stage cantilever centrifugal pump through automatic alignment and wear compensation, and is suitable for harsh working conditions.

[0016] The present invention provides a floating throat bushing for increasing the pressure of a sealing cavity. The floating throat bushing is suitable for easily vaporized media and is selected when the pressure of the sealing cavity does not meet the vaporization pressure margin.

[0017] In summary, the technical solution of this utility model solves the problems in the prior art, such as the relatively large gap in the fixed throat bushing structure, the large leakage of the sealing cavity, and the vaporization of the medium on the sealing surface when encountering easily vaporized media, which leads to the failure of lubrication of the sealing surface, causing sealing failure and affecting the normal operation of the pump. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] In the diagram: 1. Pump cover; 2. Impeller; 3. Shaft; 4. Locating pin; 5. Wave spring; 6. Locating ring; 7. Throat bushing; 8. Sealing cavity. Detailed Implementation

[0021] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this utility model or its application or use. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0024] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0025] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0026] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0027] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0028] As shown in the figure, this utility model provides a floating throat bushing for increasing the pressure of the sealing cavity. It changes the original fixed installation method and designs the throat bushing 7 as a floating type installed in the pump cover 1.

[0029] A 5mm diameter locating pin 4 is installed on the throat bushing 7. The locating pin 4 and the semi-circular notch on the pump cover 1 prevent the throat bushing 7 from rotating. A wave spring 5 is used to pre-tighten the throat bushing 7 at the end of the sealing cavity 8. The wave spring 5 is fixed by a locating ring 6 fixed in the groove of the sealing cavity 8. This allows the throat bushing 7 to float during mechanical operation, effectively isolating the sealing cavity 8 to meet a higher vaporization pressure margin.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A floating throat bushing for increasing the pressure of a sealed cavity, comprising a pump cover (1), an internal portion of the pump cover (1) is provided with a shaft (3), and an impeller (2) is assembled on the shaft (3); the internal portion of the pump cover (1) is provided with a fixed throat bushing (7) for isolating a sealed cavity (8); characterized in that: the fixed installation mode of the throat bushing (7) is changed to a floating installation mode; the throat bushing (7) is floatingly installed in the pump cover (1); a positioning pin (4) is installed on the throat bushing (7), and the positioning pin (4) is provided with a semicircular groove on the pump cover (1) to prevent rotation of the throat bushing (7).

2. The floating throat bushing for increasing the pressure of a sealed cavity according to claim 1, characterized in that: a diameter of the positioning pin (4) is 5 mm.

3. The floating throat bushing for increasing the pressure of a sealed cavity according to claim 1, characterized in that: a wave spring (5) is assembled at an end of the sealed cavity (8) to pre-tighten the throat bushing (7).

4. The floating throat bushing for increasing the pressure of a sealed cavity according to claim 3, characterized in that: a positioning ring (6) is fixedly installed in a groove of the sealed cavity (8) to fix the wave spring (5). ​ ​ ​ ​ ​ ​

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