Single stage centrifugal pump

Abstract

This utility model provides a single-stage centrifugal pump, belonging to the field of centrifugal pump technology. It solves the problems of insufficient sealing and unstable structure in existing centrifugal pumps. This utility model includes a pump volute, a closed impeller, a pump casing cover, a mechanical seal, a pump shaft, a self-flushing pipeline assembly, a constant-position oil cup, and a bearing housing. The pump casing cover is stepped and has a sealing protrusion on one side. The pump casing cover is fitted to the connecting ring and fixed by bolts, with the sealing protrusion extending into the pump volute. A sealing cavity is formed at the center of the pump casing cover, and a sealing seat is formed on the outer periphery of the sealing cavity. The mechanical seal includes a sealing cover and a sealing body. The sealing body is installed inside the sealing cavity and sleeved onto the outside of the pump shaft. Several reinforcing ribs are formed on the outer side of the sealing seat, arranged in a circular array along the circumference of the sealing seat. Several connecting protrusions are formed at the outer ends of the reinforcing ribs. A connecting flange is formed at the end of the bearing housing. This utility model has the advantages of strong sealing performance and high structural strength.

Description

Technical Field

[0001] This utility model belongs to the field of centrifugal pump technology and relates to a single-stage centrifugal pump. Background Technology

[0002] Single-stage centrifugal pumps rely on the high-speed rotation of the impeller to generate centrifugal force, converting mechanical energy into fluid kinetic energy to achieve liquid transportation. They are suitable for transporting low-viscosity clean media such as clean water and light oil, and are widely used in municipal water supply, industrial circulation, agricultural irrigation and other scenarios.

[0003] Chinese patent publication number CN214837373U discloses a single-stage centrifugal pump, including a pump casing. The pump casing has an inlet channel, a flow chamber, and an outlet channel connected in sequence. One end of the pump casing is connected to a power housing. The power housing is connected to a pump shaft. The pump shaft extends through the power housing and passes through the pump casing, and rotates synchronously to connect to an impeller located in the flow chamber. The pump casing has a structure that is radially split from the flow chamber and is divided into a pump body and a pump cover. The flow chamber is machined in half on the mating surfaces of the pump body and the pump cover to form a flow chamber when the pump body and the pump cover are mated. The pump body and the pump cover are detachably connected. The power housing is connected to the end face of the pump cover away from the pump body. The pump shaft passes through the pump cover and is connected to the impeller.

[0004] In the single-stage centrifugal pump provided by this patent, the pump casing adopts a radially split structure, and the flow chamber is spliced ​​by the interlocking surfaces of the pump body and the pump cover. High-pressure media may leak along the splicing gap, and the misalignment of the two halves of the casing will cause local stress concentration on the sealing surface, accelerating the seal failure. Utility Model Content

[0005] The purpose of this invention is to address the aforementioned problems in the existing technology by providing a single-stage centrifugal pump.

[0006] The objective of this utility model can be achieved through the following technical solution: A single-stage centrifugal pump includes a pump volute, a closed impeller, a pump casing cover, a mechanical seal, a pump shaft, a self-flushing pipeline assembly, a constant-position oil cup, and a bearing housing. The pump volute has an internal mounting cavity in which the closed impeller is installed. A connecting ring is formed on one side of the pump volute. The pump casing cover is stepped and has a sealing protrusion on one side. The pump casing cover is fitted to the connecting ring and fixed with bolts, and the sealing protrusion extends into the pump volute. A sealing cavity is formed at the center of the pump casing cover. A sealing seat is formed on the outer periphery. The pump shaft passes through the sealing cavity and the mechanical seal. The mechanical seal includes a sealing cover and a sealing body. The sealing cover is attached to the outer end of the sealing seat and fixed by bolts. The sealing body is installed inside the sealing cavity and sleeved and connected to the outside of the pump shaft. Several reinforcing ribs are formed on the outer side of the sealing seat in a circular array. Several connecting protrusions are formed at the outer ends of the reinforcing ribs. A connecting flange is formed at the end of the bearing housing. The connecting flange is attached to the outer periphery of the connecting protrusions and fixed by bolts. The pump shaft passes through the bearing housing.

[0007] In the aforementioned single-stage centrifugal pump, the front side of the mounting cavity is a sloping structure, the front end of the closed impeller is an arc-shaped structure, an annular groove is formed on the front side of the sloping structure of the mounting cavity, and a wear-resistant ring is sleeved and connected to the outer periphery of the front end of the closed impeller, with the wear-resistant ring fitting into the annular groove.

[0008] In the aforementioned single-stage centrifugal pump, a cleaning hole is provided in the sealing cover of the mechanical seal, and a connecting groove is provided on the outside of the cleaning hole. One end of the self-flushing pipeline assembly is fixedly connected to the connecting groove, and the other end of the self-flushing pipeline assembly is connected to the pump volute.

[0009] In the aforementioned single-stage centrifugal pump, a connecting seat is formed on one side of the bearing housing, and the constant-position oil cup is connected to the connecting seat and the inside of the bearing housing.

[0010] In the aforementioned single-stage centrifugal pump, a sealing end cap is installed at the connection between the pump shaft and the bearing housing.

[0011] Compared with the prior art, the single-stage centrifugal pump provided by this utility model has the following beneficial effects: 1. The stepped design of the pump casing cover, combined with the sealing protrusion extending into the pump volute, increases the sealing contact area and improves the sealing performance; 2. The reinforcing ribs of the outer circumferential array of the sealing seat enhance the structural rigidity and have strong resistance to deformation. Moreover, the connecting protrusion and the bearing housing flange fit evenly, resulting in balanced force and reduced vibration; 3. One end of the self-flushing pipeline assembly is fixedly connected to the connecting groove through a connector, and the other end is connected to the high-pressure area of ​​the pump volute. It can draw some of the transported liquid to flush and cool the mechanical seal, prevent impurities from accumulating and the sealing surface from overheating, and ensure stable sealing performance. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the exploded structure of this utility model; Figure 3 This is a schematic diagram of the pump casing cover structure; Figure 4 This is a schematic diagram of a mechanical seal structure; Figure 5 This is a schematic diagram of the internal structure of the pump volute.

[0013] In the diagram: 1. Pump volute; 11. Mounting cavity; 12. Connecting ring; 13. Inclined structure; 14. Annular groove; 2. Closed impeller; 3. Pump casing cover; 31. Sealing protrusion; 32. Sealing cavity; 33. Sealing seat; 34. Reinforcing rib; 35. Connecting protrusion; 4. Mechanical seal; 41. Sealing cover; 42. Sealing body; 43. Cleaning hole; 44. Connecting groove; 5. Pump shaft; 6. Self-flushing pipeline assembly; 7. Constant position oil cup; 8. Bearing housing; 81. Connecting flange; 82. Connecting seat; 9. Wear-resistant ring; 10. Sealing end cover. Detailed Implementation

[0014] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0015] like Figures 1 to 5 As shown, this embodiment includes a pump volute 1, a closed impeller 2, a pump housing cover 3, a mechanical seal 4, a pump shaft 5, a self-flushing pipeline assembly 6, a constant-position oil cup 7, and a bearing housing 8. The pump volute 1 has an internal mounting cavity 11, in which the closed impeller 2 is precisely installed, providing the core power for liquid pressurization. A connecting ring 12 is integrally formed on one side of the pump volute 1, serving as the connection base with the pump housing cover 3. The pump housing cover 3 has a stepped structure and an integrally formed sealing protrusion 31 on one side. During assembly, the pump housing cover 3 and the connecting ring 12 fit tightly together and are fixedly connected by circumferentially evenly distributed bolts. The sealing protrusion 31 simultaneously extends into the pump volute 1, forming a double-sealed fit to effectively prevent liquid leakage.

[0016] like Figure 3 As shown, a sealing cavity 32 is provided at the center of the pump casing cover 3, and a sealing seat 33 is integrally formed on the outer circumference of the sealing cavity 32, which provides an installation reference for the mechanical seal 4. The pump shaft 5 passes through the sealing cavity 32 and the mechanical seal 4 in sequence, realizing the dual functions of power transmission and sealing protection.

[0017] like Figures 2 to 4As shown, the mechanical seal 4 includes a sealing cover 41 and a sealing body 42. The sealing cover 41 is fitted to the outer end of the sealing seat 33 and then fastened with bolts. The sealing body 42 is installed inside the sealing cavity 32 and coaxially sleeved to the outside of the pump shaft 5 to form a dynamic sealing structure, which can effectively block the leakage of liquid in the installation cavity 11 along the pump shaft 5. The outer side of the sealing seat 33 is integrally formed with several reinforcing ribs 34 evenly distributed along its circumference. The reinforcing ribs 34 not only improve the structural rigidity of the sealing seat 33, but also disperse the stress transmission during operation. The outer end of the reinforcing ribs 34 is integrally formed with several connecting protrusions 35. The end of the bearing housing 8 is integrally formed with a connecting flange 81. The connecting flange 81 is tightly fitted to the outer circumference of the connecting protrusions 35 and then fixedly connected with bolts. The assembly is convenient and the connection is stable. The end of the pump shaft 5 away from the impeller passes through the bearing housing 8 and is provided with rotational support by the bearing assembly in the bearing housing 8.

[0018] To elaborate further, such as Figure 5 As shown, the front side of the mounting cavity 11 is designed as a sloping structure 13, and the front end of the closed impeller 2 adopts an arc-shaped structure. This structural design can optimize the liquid flow channel, reduce fluid resistance, and improve the pump's conveying efficiency. An annular groove 14 is provided on the front side of the sloping structure 13 of the mounting cavity 11. A wear-resistant ring 9 is connected to the outer periphery of the front end of the closed impeller 2 by an interference fit. The wear-resistant ring 9 fits tightly with the annular groove 14, which can reduce the wear between the closed impeller 2 and the pump volute 1, improve the flow channel sealing, and extend the service life of the equipment.

[0019] To elaborate further, such as Figure 4 As shown, the mechanical seal 4 has a cleaning hole 43 in the sealing cover 41, and a connecting groove 44 is provided around the outside of the cleaning hole 43. One end of the self-flushing pipeline assembly 6 is fixedly connected to the connecting groove 44 through a connector, and the other end is connected to the high-pressure area of ​​the pump volute 1.

[0020] To elaborate further, such as Figure 1 and Figure 2 As shown, a connecting seat 82 is integrally formed on one side of the bearing housing 8. The constant position oil cup 7 is detachably connected to the connecting seat 82 by means of threads. The constant position oil cup 7 is connected to the inside of the bearing housing 8, which can continuously replenish the bearing assembly with lubricating oil, maintain a constant oil level, and reduce friction loss. A sealing end cover 10 is installed at the connection between the pump shaft 5 and the bearing housing 8 to prevent the lubricating oil in the bearing housing 8 from leaking, and at the same time block external dust and impurities from entering, protecting the bearing assembly to work normally.

[0021] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

[0022] Although this document uses a variety of terms, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of this invention; interpreting them as any additional limitation would contradict the spirit of this invention.

Claims

1. A single-stage centrifugal pump, comprising a pump volute (1), a closed impeller (2), a pump casing cover (3), a mechanical seal (4), a pump shaft (5), a self-flushing piping assembly (6), a constant-position oil cup (7), and a bearing housing (8), characterized in that: The pump volute (1) has an installation cavity (11) inside, and the closed impeller (2) is installed in the installation cavity (11). A connecting ring (12) is formed on one side of the pump volute (1). The pump cover (3) is stepped and has a sealing protrusion (31) on one side. The pump cover (3) is attached to the connecting ring (12) and fixed by bolts, and the sealing protrusion (31) extends into the pump volute (1). A sealing cavity (32) is formed at the center of the pump cover (3), and a sealing seat (33) is formed on the outer periphery of the sealing cavity (32). The pump shaft (5) passes through the sealing cavity (32) and the mechanical seal (4). The mechanical seal (4) includes A sealing cover (41) and a sealing body (42) are provided. The sealing cover (41) is attached to the outer end of the sealing seat (33) and fixed by bolts. The sealing body (42) is installed inside the sealing cavity (32) and sleeved and connected to the outside of the pump shaft (5). A number of reinforcing ribs (34) are formed on the outer side of the sealing seat (33) in a circular array. A number of connecting protrusions (35) are formed at the outer end of the reinforcing ribs (34). A connecting flange (81) is formed at the end of the bearing housing (8). The connecting flange (81) is attached to the outer periphery of the connecting protrusions (35) and fixed by bolts. The pump shaft (5) passes through the bearing housing (8).

2. A single-stage centrifugal pump according to claim 1, characterized in that: The front side of the mounting cavity (11) is a sloping structure (13), the front end of the closed impeller (2) is an arc-shaped structure, an annular groove (14) is formed on the front side of the sloping structure (13) of the mounting cavity (11), and a wear-resistant ring (9) is sleeved and connected to the outer periphery of the front end of the closed impeller (2), and the wear-resistant ring (9) fits into the annular groove (14).

3. A single-stage centrifugal pump according to claim 1, characterized in that: The mechanical seal (4) has a cleaning hole (43) in the sealing cover (41), and a connecting groove (44) is provided on the outside of the cleaning hole (43). One end of the self-flushing pipeline assembly (6) is fixedly connected to the connecting groove (44), and the other end of the self-flushing pipeline assembly (6) is connected to the pump volute (1).

4. A single-stage centrifugal pump according to claim 1, characterized in that: A connecting seat (82) is formed on one side of the bearing housing (8), and the constant position oil cup (7) is connected to the connecting seat (82) and the constant position oil cup (7) is connected to the inside of the bearing housing (8).

5. A single-stage centrifugal pump according to claim 1, characterized in that: A sealing end cap (10) is installed at the connection between the pump shaft (5) and the bearing housing (8).

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