An intake section assembly for a segmented multistage centrifugal pump

Abstract

The application discloses a suction section assembly of a sectional multistage centrifugal pump, and relates to the field of centrifugal pumps.The suction section assembly comprises a suction body, the suction body has opposite first and second ends along the axial direction thereof, and the center of the suction body is provided with a first cavity; a suction cavity body is fixedly connected to the first end of the suction body, and part of the suction cavity body extends into the first cavity; a suction partition plate is detachably fixedly connected to the second end of the suction body, and part of the suction partition plate extends into the first cavity; and the suction cavity body, the suction body and the suction partition plate jointly enclose a suction cavity in the first cavity.The suction section assembly of the sectional multistage centrifugal pump provided in the specification can solve the technical problems of serious material waste, great processing difficulty and high manufacturing cost caused by integral forging.

Description

Technical Field

[0001] This specification relates to the field of centrifugal pump technology, and in particular to a suction section assembly of a segmental multistage centrifugal pump. Background Technology

[0002] Segmental multistage centrifugal pumps are widely used in petroleum, chemical, power, and boiler feedwater industries due to their relatively simple structure, high interchangeability of parts, ease of maintenance, and wide applicable pressure range. The suction section, as one of the main casing components of a segmental multistage centrifugal pump, has a relatively complex structure, with an internal suction chamber for guiding liquid into the first-stage impeller.

[0003] In existing technologies, suction section components are typically made by casting. However, when conveying high-temperature and high-pressure media such as boiler water and hydrocarbons, the industry trend is to require the casing to be made of forged parts in order to ensure higher reliability and pressure resistance of the pump body.

[0004] However, due to the complex shape of the internal flow channel of the suction section component, if it is forged directly as a whole, there are the following shortcomings: (1) The size of the integral forging is large and the shape is complex, the forging process is difficult, and a large machining allowance is required, resulting in low material utilization and high processing cost; (2) The internal suction cavity area is narrow, the machining tool is difficult to enter, the surface finish is difficult to guarantee, the flow loss is large, and the hydraulic performance of the pump is affected; (3) Once a forging defect occurs in a local area, the entire forging is scrapped, and the manufacturing cost risk is high.

[0005] Therefore, how to reduce material waste and processing difficulty while ensuring the high reliability brought by the forging structure of the intake section component is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0006] In view of the shortcomings of the prior art, one object of this specification is to provide a suction section assembly for a segmental multistage centrifugal pump that can solve the technical problems of serious material waste, high processing difficulty and high manufacturing cost caused by integral forging.

[0007] To achieve the above objectives, this specification provides an inlet section assembly for a segmental multistage centrifugal pump, comprising: An inhalation body having a first end and a second end opposite to each other along its axial direction; a first cavity is provided at the center of the inhalation body; An inhalation box is fixedly connected to the first end of the inhalation body, and a portion of the inhalation box extends into the first cavity; An inhalation baffle is detachably and fixedly connected to the second end of the inhalation body, and a portion of the inhalation baffle extends into the first cavity; the inhalation body, the inhalation body, and the inhalation baffle together enclose an inhalation cavity located within the first cavity.

[0008] In a preferred embodiment, the suction box is welded to the inner wall of the first end of the suction body, and the first weld is located on one side of the suction cavity, and the first weld is annular.

[0009] In a preferred embodiment, an O-ring is provided between the inhalation baffle and the inner wall surface of the second end of the inhalation body for sealing.

[0010] In a preferred embodiment, an anti-rotation pin is provided between the inhalation baffle and the inner wall surface of the second end of the inhalation body. The anti-rotation pin cooperates with the inhalation baffle and the inhalation body respectively to fix the inhalation baffle and the inhalation body.

[0011] In a preferred embodiment, the inhalation box has a second cavity at its center, and the inhalation box and the inhalation body are coaxially arranged.

[0012] In a preferred embodiment, the inhalation baffle has a third cavity at its center, and the inhalation baffle and the inhalation body are coaxially arranged.

[0013] In a preferred embodiment, the second cavity, the suction cavity, and the third cavity are sequentially connected in the axial direction.

[0014] In a preferred embodiment, the wall of the inhalation body is provided with a first through hole that communicates with the first cavity for connecting the inhalation channel.

[0015] In a preferred embodiment, the suction body is fixedly connected to a suction flange, and the suction flange has a second through hole at its center, the second through hole and the first through hole being aligned and connected.

[0016] In a preferred embodiment, the suction flange is welded to the outer wall surface of the suction body where the first through hole is located, and the second weld is located at the junction of the first through hole and the second through hole, and the second weld is annular.

[0017] Beneficial effects

[0018] The segmental multistage centrifugal pump suction section assembly provided in this embodiment separates the originally integrally forged suction section component into three independent parts: the suction body, the suction plenum, and the suction baffle. These three parts are combined to form the suction cavity. Compared to the existing integral forging scheme, the shape of each part is greatly simplified, the forging difficulty of a single part is significantly reduced, and there is no need to reserve a large machining allowance for the complex internal cavity during the forging process. This greatly improves material utilization and significantly reduces processing costs. At the same time, the split structure exposes the previously difficult-to-machine inner wall surface of the suction cavity, and the inner wall surface of each part can achieve a high surface finish through conventional machining, effectively reducing flow loss and improving the pump's hydraulic efficiency. In addition, since the three parts are forged independently, if any one part has a forging defect, only that single part needs to be scrapped, which greatly reduces manufacturing costs and significantly improves the yield. This segmental multistage centrifugal pump suction section assembly has minimal material requirements, is easy to process and assemble, and can greatly reduce costs, thereby solving the technical problems of serious material waste, high processing difficulty, and high manufacturing costs caused by integral forging.

[0019] Specific embodiments of the present invention are disclosed in detail with reference to the following description and accompanying drawings, indicating how the principles of the present invention can be adopted. It should be understood that the scope of the embodiments of the present invention is not limited thereto.

[0020] Features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0021] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, or components. Attached Figure Description

[0022] 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 only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a cross-sectional structural diagram of the suction section assembly of a segmental multistage centrifugal pump provided in this embodiment. Figure 2 This is a three-dimensional structural diagram of the suction section assembly of a segmental multistage centrifugal pump provided in this embodiment; Figure 3 for Figure 2 A three-dimensional structural diagram of the inhalation baffle from a visual perspective; Figure 4 for Figure 2 The front view; Figure 5 for Figure 2 A schematic diagram of the three-dimensional structure from another perspective; Figure 6 for Figure 5 A three-dimensional structural diagram of the inhalation baffle from a visual perspective.

[0024] Explanation of reference numerals in the attached figures: 1. Suction body; 11. First end; 12. Second end; 13. First cavity; 14. First through hole; 2. Suction box; 21. Second cavity; 3. Suction baffle; 31. Third cavity; 4. Suction chamber; 5. First weld; 6. O-ring seal; 7. Anti-rotation pin; 8. Suction flange; 81. Second through hole; 9. Second weld; 101. First axis; 102. Second axis; X, Axial direction. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions of this utility model, 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. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0026] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or may be interposed with another element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or may be interposed with another element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0028] Please see Figures 1 to 6This application provides a suction section assembly for a segmental multistage centrifugal pump, comprising: a suction body 1, a suction gland 2, and a suction baffle 3.

[0029] Among them, such as Figure 1 As shown, the suction body 1 has a first end 11 and a second end 12 opposite to each other along its axial direction X. A first cavity 13 is provided at the center of the suction body 1. Figure 2 As shown, the suction box 2 is fixedly connected to the first end 11 of the suction body 1, and a portion of the suction box 2 extends into the first cavity 13. Figure 5 As shown, the suction baffle 3 is detachably fixed to the second end 12 of the suction body 1, and part of the suction baffle 3 extends into the first cavity 13. The suction box 2, the suction body 1, and the suction baffle 3 together enclose the suction cavity 4 located within the first cavity 13. The capacity of the suction cavity 4 is less than the capacity of the first cavity 13, that is, the first cavity 13 is partially occupied by the partially extended suction box 2 and the partially extended suction baffle 3, and the remaining unoccupied space forms the suction cavity 4.

[0030] The sectional multistage centrifugal pump suction section assembly provided in this embodiment separates the originally integrally forged suction section component into three independent parts: suction body 1, suction chamber 2, and suction baffle 3. These three parts are combined to form the suction cavity 4. Compared with the existing integral forging scheme, the shape of each part is greatly simplified, the forging difficulty of a single part is significantly reduced, and there is no need to reserve a large machining allowance for the complex internal cavity during the forging process. This greatly improves material utilization and significantly reduces processing costs. At the same time, the split structure exposes the inner wall surface of the suction cavity 4, which was originally difficult to machine. The inner wall surface of each part can achieve a high surface finish through conventional machining, effectively reducing flow loss and improving the hydraulic efficiency of the pump. In addition, since the three parts are forged independently, if any one part has a forging defect, only that single part needs to be scrapped, which greatly reduces manufacturing costs and significantly improves the yield. This sectional multistage centrifugal pump suction section assembly has minimal material requirements, is easy to process and assemble, and can greatly reduce costs, thereby solving the technical problems of serious material waste, high processing difficulty, and high manufacturing costs caused by integral forging.

[0031] In this embodiment, the suction body 1, suction box 2, and suction baffle 3 are all made of forgings. Compared with castings, forgings have a denser and more uniform microstructure and better mechanical properties. Furthermore, because they are forgings, the internal flow-through parts can be machined to ensure better surface finish and reduce flow loss. Through a reasonable structural design, the components of the suction section assembly are easy to forge during the forging process, while maximizing material savings and subsequent processing costs.

[0032] In this embodiment, the suction box 2 is welded to the inner wall of the first end 11 of the suction body 1, and the first weld 5 is located on one side of the suction cavity 4. This provides sufficient space for welding operations and facilitates implementation, avoiding interference with the smoothness of the internal flow channel of the suction cavity 4 due to improper weld placement, and ensuring the integrity of the flow channel of the suction cavity 4. The first weld 5 is annular, ensuring the uniformity of the welded connection and the reliability of the seal, ensuring that the connection strength between the suction box 2 and the suction body 1 is sufficient to withstand the fluid pressure and vibration impact during pump operation, and extending the service life of the components.

[0033] In this embodiment, the suction box 2 is integrated with the suction body 1 by welding. To make welding feasible, the first weld 5 is designed on one side of the suction cavity 4 (i.e., the first end 11 of the suction body 1). The suction baffle 3 adopts an assembly structure to make the welding of the suction box 2 easy to operate.

[0034] Specifically, an O-ring 6 is provided between the suction baffle 3 and the inner wall of the second end 12 of the suction body 1 for sealing. The elastic deformation characteristics of the O-ring 6 are used to achieve a reliable seal, effectively preventing fluid leakage between the suction chamber 4 and the external environment, and ensuring the sealing performance of the suction section assembly. At the same time, the O-ring 6 is a standard part, which is easy to install, low in cost, and easy to replace and maintain, further reducing the maintenance cost of the assembly.

[0035] Furthermore, an anti-rotation pin 7 is provided between the suction baffle 3 and the inner wall surface of the second end 12 of the suction body 1. The anti-rotation pin 7 cooperates with the suction baffle 3 and the suction body 1 respectively to fix the suction baffle 3 and the suction body 1, effectively restricting the circumferential rotation of the suction baffle 3 relative to the suction body 1, ensuring the positional stability of the suction baffle 3 during pump operation, preventing problems such as wear of the O-ring seal 6, seal failure or flow channel misalignment caused by the rotation of the suction baffle 3, and further improving the operational reliability and sealing durability of the suction section assembly.

[0036] In this embodiment, the suction baffle 3 and the suction body 1 are assembled with a small gap. The O-ring seal 6 seals any possible gap leakage, and the anti-rotation pin 7 is installed for limiting, so that the suction baffle 3 and the rest of the parts become one, which is easy to assemble and disassemble.

[0037] In this embodiment, a second cavity 21 is provided at the center of the suction box 2. The suction box 2 and the suction body 1 are coaxially arranged. The second cavity 21 can accommodate the mechanical seal element of the centrifugal pump. The pump shaft passes through the second cavity 21, which is used to install the mechanical seal to prevent fluid leakage along the pump shaft.

[0038] Specifically, such as Figure 3 and Figure 6As shown, the suction baffle 3 has a third cavity 31 at its center. The suction baffle 3 and the suction body 1 are coaxially arranged, which allows the fluid flowing in through the suction chamber 4 to smoothly enter the third cavity 31 of the suction baffle 3 along the axial direction X, and then be guided to the first stage impeller. This avoids flow turbulence and local eddies caused by the eccentricity of the flow channel, reduces flow losses, and improves the hydraulic efficiency of the pump. At the same time, the coaxial arrangement ensures the symmetry and force balance of the overall structure of the suction section assembly, which is conducive to improving the structural stability of the assembly.

[0039] In this embodiment, the second cavity 21, the suction cavity 4, and the third cavity 31 are sequentially connected in the axial direction X. This allows the fluid to enter the suction cavity 4 from the suction channel. Since the second cavity 21 is a chamber with a mechanical seal, the fluid naturally enters the third cavity 31 and is then guided to the first-stage impeller, forming a smooth and continuous flow path. This avoids energy loss caused by sudden changes in direction or cross-section when the fluid flows through different cavities, further reducing flow resistance and improving the overall hydraulic efficiency of the pump.

[0040] Specifically, the wall of the suction body 1 is provided with a first through hole 14 that communicates with the first cavity 13, for connecting the suction channel (i.e., the external liquid inlet pipe), so that the fluid in the external pipe can smoothly enter the first cavity 13 through the first through hole 14. This design is simple in structure, has a short flow path, and reduces the flow resistance of the fluid before it enters the pump body. At the same time, the first through hole 14 is located on the wall of the suction body 1 and does not occupy the axial X space of the suction body 1, which helps to maintain the axial X compactness of the suction section assembly. The axial direction of the suction channel is perpendicular to the axial X direction of the suction body 1.

[0041] In this embodiment, such as Figure 2 and Figure 4 As shown, the suction body 1 is fixedly connected to a suction flange 8. The suction flange 8 has a second through hole 81 at its center, which is aligned with and connected to the first through hole 14. The suction flange 8 enables standard flange connection to the external suction pipeline, facilitating the installation and disassembly of the pump body and pipeline, and improving on-site assembly efficiency and sealing reliability. The alignment of the second through hole 81 with the first through hole 14 ensures unobstructed flow, avoiding throttling effects and flow losses caused by hole misalignment.

[0042] Specifically, such as Figure 1As shown, the suction flange 8 is welded to the outer wall surface of the suction body 1 where the first through hole 14 is located, and the second weld 9 is located at the junction of the first through hole 14 and the second through hole 81, making the welding operation easy to perform at this position and ensuring the weld quality. The second weld 9 is annular, ensuring the uniformity of the flange connection and the reliability of the seal, and ensuring that the connection strength between the suction flange 8 and the suction body 1 is sufficient to withstand the tension of the pipeline system and the vibration during pump operation, thereby improving the overall structural strength and long-term operational reliability of the assembly.

[0043] like Figure 1 As shown, the axes of the suction body 1, the suction chamber 2, and the suction baffle 3 are all the first axis 101, which extends along the axial direction X. The axes of the first through hole 14 and the second through hole 81 are both the second axis 102, which extends in a direction perpendicular to the axial direction X.

[0044] It should be noted that in the description of this specification, the terms "first," "second," etc., are used only for descriptive purposes and to distinguish similar objects; there is no order between them, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this specification, unless otherwise stated, "a plurality of" means two or more.

[0045] Any numerical values ​​cited herein include all values ​​ranging from a lower limit to an upper limit, increasing by one unit, with at least two units between any lower and any higher value. For example, if the quantity of a component or the value of a process variable (e.g., temperature, pressure, time, etc.) is described as being from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, the purpose is to illustrate that values ​​such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 are also explicitly listed in this specification. For values ​​less than 1, a unit is appropriately considered to be 0.0001, 0.001, 0.01, 0.1, etc. These are merely examples intended for explicit expression, and it can be assumed that all possible combinations of values ​​listed between the minimum and maximum values ​​are explicitly described in this specification in a similar manner.

[0046] Unless otherwise stated, all ranges include the endpoints and all numbers between them. The terms "approximately" or "about" used with ranges apply to both endpoints of the range. Thus, "approximately 20 to 30" is intended to cover "approximately 20 to approximately 30," including at least the specified endpoints.

[0047] All articles and references disclosed herein, including patent applications and publications, are incorporated herein by reference for various purposes. The term “substantially constitutes…” used to describe a combination should include the identified elements, components, parts, or steps, as well as other elements, components, parts, or steps that do not substantially affect the essential novelty of the combination. The use of the terms “comprising” or “including” to describe combinations of elements, components, parts, or steps herein also contemplates embodiments substantially constituted by such elements, components, parts, or steps. The use of the term “may” herein is intended to indicate that any described attribute included by “may” is optional.

[0048] Multiple elements, components, parts, or steps can be provided by a single integrated element, component, part, or step. Alternatively, a single integrated element, component, part, or step can be divided into multiple separate elements, components, parts, or steps. The use of "a" or "an" to describe an element, component, part, or step does not imply the exclusion of other elements, components, parts, or steps.

[0049] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the appended claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference.

Claims

1. A suction section assembly for a segmental multistage centrifugal pump, characterized in that, include: An inhalation body having a first end and a second end opposite to each other along its axial direction; a first cavity is provided at the center of the inhalation body; An inhalation box is fixedly connected to the first end of the inhalation body, and a portion of the inhalation box extends into the first cavity; An inhalation baffle is detachably and fixedly connected to the second end of the inhalation body, and a portion of the inhalation baffle extends into the first cavity; the inhalation chamber, the inhalation body, and the inhalation baffle together enclose an inhalation cavity located within the first cavity; an O-ring seal is provided between the inhalation baffle and the inner wall surface of the second end of the inhalation body for sealing; an anti-rotation pin is also provided between the inhalation baffle and the inner wall surface of the second end of the inhalation body, the anti-rotation pin cooperating with the inhalation baffle and the inhalation body respectively to fix the inhalation baffle and the inhalation body.

2. The suction section assembly of the segmental multistage centrifugal pump according to claim 1, characterized in that, The suction box is welded to the inner wall of the first end of the suction body, and the first weld is located on one side of the suction cavity, and the first weld is annular.

3. The suction section assembly of the segmental multistage centrifugal pump according to claim 1, characterized in that, The inhalation box has a second cavity at its center, and the inhalation box and the inhalation body are coaxially arranged.

4. The suction section assembly of the segmental multistage centrifugal pump according to claim 3, characterized in that, The inhalation baffle has a third cavity in the center, and the inhalation baffle and the inhalation body are coaxially arranged.

5. The suction section assembly of the segmental multistage centrifugal pump according to claim 4, characterized in that, The second cavity, the suction cavity, and the third cavity are sequentially connected in the axial direction.

6. The suction section assembly of the segmental multistage centrifugal pump according to claim 1, characterized in that, The wall of the inhalation body is provided with a first through hole that communicates with the first cavity for connecting the inhalation channel.

7. The suction section assembly of the segmental multistage centrifugal pump according to claim 6, characterized in that, The suction body is fixedly connected to a suction flange, and the suction flange has a second through hole at its center. The second through hole and the first through hole are aligned and connected.

8. The suction section assembly of the segmental multistage centrifugal pump according to claim 7, characterized in that, The suction flange is welded to the outer wall surface of the suction body where the first through hole is located, and the second weld is located at the junction of the first through hole and the second through hole, and the second weld is annular.

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