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

Abstract

The invention relates to a guide vane structure for thermal 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 fixed on the reverse impeller; 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 the 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] The invention relates to a guide vane structure, in particular to a guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller, which ensures the stability and reliability of a water pump operation. Background Art

[0002] Among segmental multistage centrifugal pumps, symmetrically arranged impeller self-balancing multistage centrifugal pumps are gradually recognized by customers due to their advantages in service life and volumetric efficiency compared with traditional balancing disc and balancing drum multistage centrifugal pumps. At the same time, they are also gradually becoming an irreplaceable structural form due to their absolute advantages in variable frequency operation, frequent start and stop or changing operating conditions.

[0003] The general assembly sequence of the segmented self-balancing multistage centrifugal pump is: positive impeller - positive guide vane - positive middle section - ... - discharge section - reverse guide vane - reverse impeller - reverse middle section - ..., and the disassembly process is exactly the opposite of the assembly sequence; in the design of high-pressure, high-temperature, and high-speed multistage pumps, due to the influence of the pump on vibration resistance and thermal shock, the installation method of the impeller and the shaft is mostly designed for thermal disassembly (that is: an interference fit is adopted between the impeller and the shaft. When installing, the impeller is first placed in a heating box and heated to about 200°C, then quickly taken out and put on the pump shaft and positioned; when disassembling, the impeller hub must be quickly heated circumferentially, and the heating is stopped when the impeller becomes loose, and the impeller is quickly pulled out along the shaft). When disassembling the reverse impeller in this disassembly method, since the hub of the reverse impeller is hidden in the reverse guide vane, the hub of the reverse impeller cannot be quickly heated circumferentially, so the disassembly process of the reverse impeller cannot be carried out normally. Summary of the invention

[0004] In view of the above problems, the main purpose of the present invention is to provide a guide vane structure for thermal removal and installation of a segmented self-balancing multi-stage pump impeller, which ensures the stability and reliability of the water pump operation.

[0005] The present invention solves the above-mentioned technical problems through the following technical scheme: a guide vane structure for thermal disassembly and installation of a segmented self-balancing multi-stage pump impeller, the guide vane structure for thermal disassembly and installation of a segmented self-balancing multi-stage pump impeller comprises: an anti-guide vane, an anti-impeller, an impeller retaining ring, and an anti-center section, the anti-guide vane comprises two halves of an anti-guide vane body integrated along a split surface; the anti-guide vane is installed in a pump casing, and an interference fit is adopted between the anti-impeller and the pump shaft. During installation, the anti-impeller is heated and then sleeved on the pump shaft, and the anti-guide vane is pressed down so that the rear cover plate of the anti-impeller contacts the anti-guide vane, the impeller retaining ring is installed, and then the anti-impeller is pulled up to the positioning position of the impeller retaining ring to complete the thermal sleeve of the anti-impeller; then the anti-center section is installed, and the step stop on the anti-center section is used to hold the anti-guide vane tightly, and a micro-interference fit is adopted between the anti-center section and the anti-guide vane.

[0006] In a specific implementation example of the present invention, the reverse guide vane is a radial guide vane, and the reverse guide vane positive blade flow channel is a closed type or an open type.

[0007] In a specific implementation example of the present invention, the two halves of the reverse guide vane body in the entire reverse guide vane are integrally formed.

[0008] In a specific implementation example of the present invention, the counter-impeller is a closed impeller, and an interference fit is adopted between the counter-impeller and the pump shaft. During installation, the counter-impeller is heated and then sleeved on the pump shaft.

[0009] In a specific implementation example of the present invention, the entire counter-impeller is formed in one piece.

[0010] In a specific implementation example of the present invention, the impeller clamping ring is an open clamping ring, and the impeller clamping ring is made of high-strength stainless steel and is a heat-treated impeller clamping ring.

[0011] In a specific implementation example of the present invention, the entire impeller clamping ring is integrally formed.

[0012] In a specific implementation example of the present invention, the entire anti-center section is formed in one piece.

[0013] In a specific implementation example of the present invention, the installation process of the structure is as follows: adopt vertical installation, place the reverse guide vane on the pump casing at a predetermined position, then quickly insert the heated reverse impeller into the pump shaft and press it down until the impeller rear cover plate contacts the reverse guide vane, quickly install the impeller retaining ring, and then pull the impeller up to the retaining ring positioning position to complete the hot fitting of the impeller; finally, install the reverse center section, use the step stop on the reverse center section to hold the reverse guide vane tightly, and complete the installation of the first stage of the reverse section of the segmented self-balancing multi-stage centrifugal pump.

[0014] In a specific implementation example of the present invention, the disassembly process of the structure is as follows: adopt vertical disassembly, after removing the anti-middle section, take out the anti-guide vane radially in half, use an air gun to quickly heat the impeller hub circumferentially, so that the impeller hub quickly heats up and expands, and when the anti-impeller can slide along the shaft, press down the anti-impeller, leak out the impeller retaining ring and quickly move it out, and then pull out the anti-impeller along the shaft to complete the removal of the first-stage impeller.

[0015] The positive progressive effect of the present invention is that the guide vane structure for thermal disassembly and installation of the impeller of a segmented self-balancing multistage pump provided by the present invention has the following advantages compared with the common technology: the present invention is a split guide vane, which is installed in the reverse section of the self-balancing multistage pump where the impeller and the shaft are thermally fitted. When the pump needs to repair and replace the impeller, the guide vane can be radially removed after removing the reverse middle section, so that the reverse impeller hub is exposed within the operable range, and then the reverse impeller hub is quickly heated circumferentially with an air gun to quickly heat and expand the reverse impeller hub, thereby realizing the thermal disassembly and installation of the impeller and the shaft in the self-balancing multistage pump; the stability and reliability of the water pump operation are guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a schematic diagram (cross-sectional view) of the impeller arrangement of a segmented self-balancing multi-stage pump in the present invention.

[0017] Figure 2 It is a schematic diagram of the structure of the reverse guide vane in the present invention.

[0018] Figure 3 It is a schematic diagram of the structure of the counter impeller in the present invention.

[0019] Figure 4 It is a schematic structural diagram of the impeller retaining ring in the present invention.

[0020] Figure 5 It is a schematic structural diagram of the anti-middle section in the present invention.

[0021] Figure 6-1 It is the installation schematic diagram of the present invention.

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

[0023] The following are the names corresponding to the labels in the present invention:

[0024] Reverse guide vane (1), reverse impeller (2), impeller retaining ring (3), reverse middle section (4) DETAILED DESCRIPTION

[0025] Preferred embodiments of the present invention are given below in conjunction with the accompanying drawings to illustrate the technical solutions of the present invention in detail.

[0026] Figure 1 FIG. 1 is a schematic diagram (sectional view) of the impeller arrangement of the segmented self-balancing multi-stage pump in the present invention. Figure 1 As shown: the present invention proposes a guide vane structure for hot removal and installation of a segmented self-balancing multistage pump impeller, the guide vane structure for hot removal and installation of a segmented self-balancing multistage pump impeller comprises: an anti-guide vane 1, an anti-impeller 2, an impeller retaining ring 3, and an anti-center section 4, the anti-guide vane 1 comprises two halves of an anti-guide vane body integrated along a split surface; the anti-guide vane 1 is installed in a pump casing, and an interference fit is adopted between the anti-impeller 2 and the pump shaft. During installation, the anti-impeller 2 is heated and then sleeved on the pump shaft, and the anti-guide vane 1 is pressed down so that the rear cover plate of the anti-impeller 2 contacts the anti-guide vane 1, the impeller retaining ring 3 is installed, and then the anti-impeller 2 is pulled up to the positioning position of the impeller retaining ring 3 to complete the hot sleeve of the anti-impeller 2; then the anti-center section 4 is installed, and the anti-guide vane 2 is tightly held by the step stop on the anti-center section to complete the installation of the first stage of the reverse section of the segmented self-balancing multistage centrifugal pump. A slight interference fit is adopted between the anti-middle section 4 and the anti-guide vane 1, so that the anti-guide vane split surfaces can be more closely fitted together, thereby preventing water from flowing forward and backward of the guide vane.

[0027] Figure 2 Schematic diagram of the structure of the reverse guide vane in the present invention, as shown in Figure 2As shown: the reverse guide vane 1 in the present invention is a radial guide vane, and the reverse guide vane positive blade flow channel is closed or open ( Figure 1 The one shown is an open type). In the present invention, the two halves of the reverse guide vane body in the entire reverse guide vane 1 are integrally formed.

[0028] Figure 3 Schematic diagram of the structure of the counter impeller in the present invention, as shown in Figure 3 As shown: the counter-impeller 2 in the present invention is a closed impeller, and an interference fit is adopted between the counter-impeller 2 and the pump shaft. When installing, the counter-impeller is heated and then sleeved on the pump shaft. The entire counter-impeller 2 is integrally formed.

[0029] Figure 4 Schematic diagram of the structure of the impeller retaining ring in the present invention, as shown in Figure 4 As shown: the impeller clamp ring 3 is an open clamp ring, which is made of high-strength stainless steel and heat-treated. The entire impeller clamp ring 3 is integrally formed; the entire anti-center section 4 (participate in Figure 5 )One-piece molding.

[0030] The general manufacturing scheme of the anti-guide vane in the present invention is as follows: the anti-guide vane is roughly processed and then cut along the center section, the cut section is polished and ground, and then the two halves of the cut anti-guide vane are combined along the split surface, and then the anti-guide vane is finely processed using special tooling.

[0031] Reference Figure 1 and 6-1 The installation process of the present invention is as follows: adopt vertical installation, place the reverse guide vane on the pump housing (reverse middle section) at a predetermined position, then quickly insert the heated reverse impeller into the pump shaft and press it down until the impeller rear cover plate contacts the reverse guide vane, quickly install the impeller clamping ring, and then pull the impeller up to the clamping ring positioning position to complete the hot-fitting of the impeller; finally, install the reverse middle section, use the step stop on the reverse middle section to hold the reverse guide vane tightly, and complete the installation of the first stage of the reverse section of the segmental self-balancing multi-stage centrifugal pump.

[0032] Reference Figure 1 and 6-2 The disassembly process of the present invention is as follows: adopt vertical disassembly, after removing the anti-middle section 4, take out the anti-guide vane 1 radially in half, use an air gun to quickly heat the impeller hub circumferentially, so that the impeller hub quickly heats up and expands, and when the anti-impeller 2 can slide along the axis, press down the anti-impeller 2, leak out the impeller retaining ring 3 and quickly move it out, and then pull out the anti-impeller 2 along the axis to complete the removal of the first-stage impeller.

[0033] The invention improves the stability of the segmental self-balancing multi-stage centrifugal pump under cold operating conditions and the feasibility under hot operating conditions.

[0034] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected, and the scope of the present invention to be protected is defined by the attached claims and their equivalents.

Claims

1. A guide vane structure for thermal removal and installation of a segmental self-balancing multi-stage pump impeller, characterized in that: The guide vane structure used for thermal disassembly and installation of the impeller of a segmented self-balancing multi-stage pump comprises: an anti-guide vane, an anti-impeller, an impeller retaining ring, and an anti-center section. The anti-guide vane comprises two anti-guide vane halves that are integrated along a split surface. The anti-guide vane is installed in a pump casing, and an interference fit is adopted between the anti-impeller and the pump shaft. During installation, the anti-impeller is heated and then sleeved on the pump shaft, and the anti-guide vane is pressed down so that the rear cover plate of the anti-impeller contacts the anti-guide vane, the impeller retaining ring is installed, and then the anti-impeller is pulled up to the positioning position of the impeller retaining ring to complete the thermal sleeve of the anti-impeller. Then, the anti-center section is installed, and the anti-guide vane is tightly held by the step stop on the anti-center section, and a micro-interference fit is adopted between the anti-center section and the anti-guide vane.

2. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The reverse guide vane is a radial guide vane, and the reverse guide vane positive blade flow channel is closed or open.

3. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 2, characterized in that: The two halves of the anti-guide vane body in the entire anti-guide vane are formed in one piece.

4. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The counter impeller is a closed impeller, and an interference fit is adopted between the counter impeller and the pump shaft. During installation, the counter impeller is heated and then put on the pump shaft.

5. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1 or 4, characterized in that: The entire counter-impeller is formed in one piece.

6. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The impeller retaining ring is an open retaining ring, which is made of high-strength stainless steel and is heat-treated.

7. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 6, characterized in that: The entire impeller retaining ring is formed in one piece.

8. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The entire anti-center section is molded in one piece.

9. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The installation process of the structure is as follows: adopt vertical installation, place the reverse guide vane on the pump casing at a predetermined position, then quickly insert the heated reverse impeller into the pump shaft and press it down until the impeller rear cover plate contacts the reverse guide vane, quickly install the impeller retaining ring, and then pull the impeller up to the retaining ring positioning position to complete the hot fitting of the impeller; finally, install the reverse middle section, use the step stop on the reverse middle section to hold the reverse guide vane tightly, and complete the installation of the first stage of the reverse section of the segmental self-balancing multi-stage centrifugal pump.

10. The guide vane structure for thermal disassembly and assembly of a segmented self-balancing multi-stage pump impeller according to claim 1, characterized in that: The disassembly process of the structure is as follows: adopt vertical disassembly, after removing the anti-middle section, take out the anti-guide vane radially in half, use an air gun to quickly heat the impeller hub circumferentially to make the impeller hub quickly heat up and expand, and when the anti-impeller can slide along the shaft, press down the anti-impeller, leak out the impeller retaining ring and quickly move it out, and then pull out the anti-impeller along the shaft to complete the removal of the first-stage impeller.

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