Guide vane structure for hot disassembly and assembly of segmental self-balancing multi-stage pump impeller

Abstract

The utility model relates to a guide vane structure for the hot disassembly and assembly of a segmental self-balancing multistage pump impeller, the structure comprises a reverse guide vane, a reverse impeller, an impeller snap ring and a reverse middle section, the reverse impeller is in interference fit with a pump shaft, during installation, the reverse impeller is sleeved on the pump shaft after being heated, and the reverse guide vane is pressed down, so that a rear cover plate of the reverse impeller is in contact with the reverse guide vane, and the reverse guide vane is pressed down; an impeller clamping ring is installed, then the reverse impeller is pulled upwards to the positioning position of the impeller clamping ring, and hot sleeving of the reverse impeller is completed; and then the reverse middle section is installed, the reverse guide vane is tightly held through a step spigot on the reverse middle section, and the reverse middle section and the reverse guide vane are in micro interference fit. When the impeller of the pump needs to be maintained and replaced, the guide vane can be disassembled in the radial direction after the reverse middle section is removed, the reverse impeller hub is exposed in an operable range, then the reverse impeller hub is rapidly and circumferentially heated through an air gun, the reverse impeller hub is rapidly heated and expanded, and the thermal disassembly and assembly performance of the impeller and a shaft in the self-balancing type multi-stage pump is achieved; and the stability and reliability of water pump operation are ensured.

Description

Technical Field

[0001] This utility model relates to a guide vane structure, specifically a guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump, which ensures the stability and reliability of pump operation. Background Technology

[0002] Among segmental multistage centrifugal pumps, the symmetrical impeller self-balancing multistage centrifugal pump is gradually being recognized by customers for its advantages in service life and volumetric efficiency compared with traditional balance disc and balance drum multistage centrifugal pumps. At the same time, it is gradually becoming an irreplaceable structural form due to its absolute advantages in variable frequency operation, frequent start-stop or changing working conditions.

[0003] The general assembly sequence of a segmental self-balancing multistage centrifugal pump is: positive impeller—positive guide vane—central section—…—discharge section—reverse guide vane—reverse impeller—reverse central section—… The disassembly process is exactly the reverse of the assembly sequence. In the design of high-pressure, high-temperature, and high-speed multistage pumps, due to the pump's resistance to vibration and thermal shock, the impeller and shaft are often designed for hot disassembly (i.e., the impeller and shaft use an interference fit; during installation, the impeller is first placed in a heating box and heated to about 200°C, then quickly removed and fitted onto the pump shaft and positioned; during disassembly, the impeller hub must be rapidly circumferentially heated, and heating is stopped when the impeller becomes loose, while the impeller is quickly pulled out along the shaft). In this disassembly method, when disassembling the reverse impeller, because the hub of the reverse impeller is hidden inside the reverse guide vane, it is impossible to rapidly circumferentially heat the hub of the reverse impeller, so the disassembly process of the reverse impeller cannot be carried out normally. Utility Model Content

[0004] To address the aforementioned problems, the main objective of this utility model is to provide a guide vane structure for hot disassembly and assembly of the impeller in a segmental self-balancing multistage pump, which ensures the stability and reliability of pump operation.

[0005] This utility model solves the above-mentioned technical problems through the following technical solution: a guide vane structure for hot disassembly and assembly of a segmental self-balancing multistage pump impeller, the guide vane structure for hot disassembly and assembly of a segmental self-balancing multistage pump impeller includes: a reverse guide vane, a reverse impeller, an impeller retaining ring, and a reverse middle section. The reverse guide vane includes two halves of the reverse guide vane body integrated along the split surface; the reverse guide vane is installed inside the pump casing, and the reverse impeller and the pump shaft are fitted with an interference fit. During installation, the reverse impeller is heated and then fitted onto the pump shaft, and the reverse guide vane is pressed down so that the rear cover plate of the reverse impeller contacts the reverse guide vane. The impeller retaining ring is then inserted, and the reverse impeller is pulled up to the positioning position of the impeller retaining ring to complete the hot fitting of the reverse impeller; then the reverse middle section is inserted, and the reverse guide vane is held tightly by the stepped stop on the reverse middle section. The reverse middle section and the reverse guide vane are fitted with a slight interference fit.

[0006] In a specific embodiment of this utility model, the anti-guide vane is a radial guide vane, and the flow channel of the positive blade of the anti-guide vane is either closed or open.

[0007] In a specific embodiment of this utility model, both halves of the anti-missile blade are integrally formed.

[0008] In a specific embodiment of this utility model, the reverse impeller is a closed impeller, and the reverse impeller and the pump shaft are fitted with an interference fit. During installation, the reverse impeller is heated and then fitted onto the pump shaft.

[0009] In a specific embodiment of this utility model, the entire anti-impeller is integrally formed.

[0010] In a specific embodiment of this utility model, the impeller retaining ring is an open retaining ring, and the impeller retaining ring is made of high-strength stainless steel and has undergone heat treatment.

[0011] In a specific embodiment of this utility model, the entire impeller retaining ring is integrally formed.

[0012] In a specific embodiment of this utility model, the entire anti-middle section is integrally formed.

[0013] In a specific embodiment of this utility model, the installation process of the structure is as follows: A vertical installation is adopted, with the guide vane placed on the pump casing at a predetermined position. Then, the heated impeller is quickly fitted onto the pump shaft and pressed down until the impeller rear cover plate contacts the guide vane. The impeller retaining ring is quickly installed, and the impeller is pulled up to the retaining ring positioning position to complete the heat fitting of the impeller. Finally, the intermediate section is installed, and the stepped stop on the intermediate section is used to hold the guide vane tightly, completing the installation of the first stage of the reverse section of the segmental self-balancing multistage centrifugal pump.

[0014] In a specific embodiment of this utility model, the disassembly process of the structure is as follows: a vertical disassembly is adopted. After the reverse middle section is removed, the reverse guide vane is removed radially in half. The impeller hub is heated quickly in a circular motion using an air gun, so that the impeller hub heats up and expands rapidly. When the reverse impeller can slide along the shaft, the reverse impeller is pressed down to expose the impeller retaining ring and is quickly moved out. Then the reverse impeller is pulled out along the shaft to complete the disassembly of the first-stage impeller.

[0015] The positive and progressive effects of this utility model are as follows: Compared with common technologies, the guide vane structure provided by this utility model for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump has the following advantages: This utility model is a split guide vane, which is installed in the reverse section of the self-balancing multistage pump where the impeller and shaft are thermally fitted. When the pump needs to be repaired or the impeller replaced, this guide vane can be radially removed after the reverse section is removed, exposing the impeller hub to the operable range. Then, the impeller hub is rapidly heated circumferentially with an air gun, causing the impeller hub to heat up and expand rapidly, thus achieving hot disassembly and assembly of the impeller and shaft in the self-balancing multistage pump; ensuring the stability and reliability of the pump operation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram (sectional view) of the impeller arrangement of the segmental self-balancing multistage pump of this utility model.

[0017] Figure 2 This is a schematic diagram of the anti-guide vane in this utility model.

[0018] Figure 3 This is a schematic diagram of the reverse impeller in this utility model.

[0019] Figure 4 This is a schematic diagram of the impeller retaining ring in this utility model.

[0020] Figure 5 This is a schematic diagram of the reverse middle section in this utility model.

[0021] Figure 6-1 This is a schematic diagram of the installation of this utility model.

[0022] Figure 6-2 This is a disassembly diagram of the present invention.

[0023] The following are the names corresponding to the reference numerals in this utility model:

[0024] Anti-guide blade (1), anti-impeller (2), impeller retainer (3), anti-middle section (4) Detailed Implementation

[0025] The preferred embodiments of this utility model are given below with reference to the accompanying drawings to illustrate the technical solution of this utility model in detail.

[0026] Figure 1 This is a schematic diagram (sectional view) of the impeller arrangement of the segmental self-balancing multistage pump of this utility model. Figure 1 As shown: This utility model proposes a guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump includes: a reverse guide vane 1, a reverse impeller 2, an impeller retaining ring 3, and a reverse intermediate section 4. The reverse guide vane 1 includes two halves of the reverse guide vane body that are integrally joined along the split surface. The reverse guide vane 1 is installed inside the pump casing. The reverse impeller 2 is pressurized with the pump shaft. During installation, the reverse impeller 2 is heated and then fitted onto the pump shaft. The reverse guide vane 1 is then pressed down so that the rear cover plate of the reverse impeller 2 contacts the reverse guide vane 1. The impeller retaining ring 3 is then inserted, and the reverse impeller 2 is pulled up to the positioning position of the impeller retaining ring 3 to complete the hot fitting of the reverse impeller 2. Then the reverse intermediate section 4 is inserted, and the reverse guide vane 2 is held in place by the stepped stop on the reverse intermediate section, completing the installation of the first stage of the reverse section of the segmental self-balancing multistage centrifugal pump. The anti-mid section 4 and the anti-guide vane 1 are fitted with a slight interference fit, which allows the anti-guide vane's split surfaces to fit together more tightly, preventing water from flowing between the front and back of the guide vane.

[0027] Figure 2 This is a schematic diagram of the anti-missile blade in this utility model, as shown below. Figure 2 As shown: In this utility model, the anti-guide vane 1 is a radial guide vane, and the flow channel of the positive blade of the anti-guide vane is either closed or open. Figure 1 The given form is an open form.

[0028] In this invention, both halves of the anti-missile blade 1 are integrally formed.

[0029] Figure 3 This is a schematic diagram of the reverse impeller in this utility model, as shown below. Figure 3 As shown: In this utility model, the reverse impeller 2 is a closed impeller. The reverse impeller 2 and the pump shaft are fitted with an interference fit. During installation, the reverse impeller is heated and then fitted onto the pump shaft. The entire reverse impeller 2 is integrally formed.

[0030] Figure 4 This is a schematic diagram of the impeller retaining ring in this utility model, as shown below. Figure 4 As shown: Impeller retaining ring 3 is an open retaining ring, made of high-strength stainless steel and heat-treated. The entire impeller retaining ring 3 is integrally formed; the entire reverse section 4 (participating) Figure 5 It is molded in one piece.

[0031] The general manufacturing scheme of the anti-missile blade in this utility model is as follows: after rough machining, the anti-missile blade is cut open along the cross-section through the center, the cut cross-section is polished and ground, then the two halves of the anti-missile blade are joined together along the split surface, and then the anti-missile blade is precision machined using special tooling.

[0032] Reference Figure 1 and 6-1 The installation process of this utility model is as follows: A vertical installation is adopted. The guide vane is placed on the pump casing (reverse section) at a predetermined position. Then, the heated reverse impeller is quickly fitted onto the pump shaft and pressed down until the impeller rear cover plate contacts the guide vane. The impeller retaining ring is quickly installed, and then the impeller is pulled up to the retaining ring positioning position to complete the heat fitting of the impeller. Finally, the reverse section is installed, and the stepped stop on the reverse section is used to hold the guide vane tightly, completing the installation of the first stage of the reverse section of the segmental self-balancing multistage centrifugal pump.

[0033] Reference Figure 1 and 6-2 The disassembly process of this utility model is as follows: Vertical disassembly is adopted. After removing the reverse middle section 4, the reverse guide vane 1 is removed radially in half. The impeller hub is heated quickly in a circular motion using an air gun, so that the impeller hub heats up and expands rapidly. When the reverse impeller 2 can slide along the shaft, the reverse impeller 2 is pressed down to expose the impeller retaining ring 3 and quickly moved out. Then, the reverse impeller 2 is pulled out along the shaft to complete the disassembly of the first-stage impeller.

[0034] This invention improves the stability of segmental self-balancing multistage centrifugal pumps under cold operating conditions and their feasibility under hot operating conditions.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection of this utility model as defined by the appended claims and their equivalents.

Claims

1. A guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump, characterized in that: The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump includes: a reverse guide vane, a reverse impeller, an impeller retaining ring, and a reverse intermediate section. The reverse guide vane comprises two halves of the reverse guide vane body integrated along the split surface. The reverse guide vane is installed inside the pump casing. The reverse impeller and the pump shaft are fitted with an interference fit. During installation, the reverse impeller is heated and then fitted onto the pump shaft. The reverse guide vane is then pressed down so that the rear cover plate of the reverse impeller contacts the reverse guide vane. The impeller retaining ring is then inserted, and the reverse impeller is pulled up to the positioning position of the impeller retaining ring to complete the hot fitting of the reverse impeller. The reverse intermediate section is then inserted, and the stepped stop on the reverse intermediate section is used to hold the reverse guide vane tightly. The reverse intermediate section and the reverse guide vane are fitted with a slight interference fit.

2. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 1, characterized in that: The anti-guide vane is a radial guide vane, and the flow channel of the positive blade of the anti-guide vane is either closed or open.

3. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 2, characterized in that: Both halves of the anti-missile blade are integrally formed.

4. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 1, characterized in that: The reverse impeller is a closed impeller.

5. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 1 or 4, characterized in that: The entire reverse impeller is molded as a single piece.

6. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 1, characterized in that: The impeller retainer is an open retainer made of high-strength stainless steel and heat-treated.

7. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 6, characterized in that: The entire impeller retaining ring is molded as a single piece.

8. The guide vane structure for hot disassembly and assembly of the impeller of a segmental self-balancing multistage pump according to claim 1, characterized in that: The entire anti-mid section is molded as a single piece.

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