Centrifugal pump impeller and wear ring sealing device and centrifugal pump

Abstract

The utility model belongs to the technical field of centrifugal pumps, and provides a centrifugal pump impeller and wear ring sealing device and a centrifugal pump, and the centrifugal pump impeller and wear ring sealing device comprises an impeller wear ring which is fixedly arranged on an impeller of the centrifugal pump; the corrugated pipe and a pump body of the centrifugal pump are coaxially arranged, one end of the corrugated pipe and the inner wall of the pump body are fixedly installed in a sealed mode, the pump body wear ring is installed at the end, close to the impeller wear ring, of the corrugated pipe, and the end face of the impeller wear ring can be attached to the end face of the pump body wear ring. The spring seat is fixedly arranged at one end, close to the impeller wear ring, of the corrugated pipe; the spring is arranged in the pump body and arranged on the periphery of the corrugated pipe in a sleeving mode, one end of the spring is connected to the spring base, and the other end of the spring abuts against the pump body.

Description

Technical Field

[0001] The utility model belongs to the technical field of centrifugal pumps, in particular to a centrifugal pump impeller and mouth ring sealing device and a centrifugal pump. Background Art

[0002] Water pumps play a vital role in the circulation systems of various living and production facilities, and are also a significant source of power loss. The leakage between the pump body and impeller of a centrifugal pump is one of the factors that affect the pump's operating efficiency.

[0003] like Figure 1 As shown, in existing centrifugal pump designs, a large gap is intentionally created to ensure frictionless and smooth operation between the pump body and impeller. This measure effectively avoids wear that could result from direct contact between the two and ensures the free rotation of the impeller. However, due to the low pressure at the centrifugal pump's impeller inlet, this design creates a high-pressure area at the outlet due to dynamic forces. This pressure differential causes some liquid to flow back through the gap between the impeller and the pump body ring. Especially when the gap is large, the backflow rate increases significantly, resulting in large hydraulic volume losses, which directly reduces the efficiency of the pump and becomes a major obstacle to performance improvement. Therefore, it is important to design an appropriate gap for the centrifugal pump to ensure frictionless operation between the pump body and impeller during operation. At the same time, it can also ensure that leakage between the pump body ring and the impeller is reduced or even eliminated during operation. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of the utility model is to provide a centrifugal pump impeller and mouth ring sealing device and a centrifugal pump, a pump body mouth ring is provided at the pump body, and an impeller mouth ring is provided at the impeller. When the centrifugal pump is working, the pump body mouth ring and the impeller mouth ring are in operation, and the two end faces fit together to isolate the inlet and outlet, and no liquid flows back from the outlet to the inlet, thereby ensuring zero leakage of the centrifugal pump during operation.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] A centrifugal pump impeller and ring sealing device includes an impeller ring fixedly mounted on the impeller of the centrifugal pump;

[0007] A bellows and a pump body ring, wherein the bellows is coaxially arranged with the pump body of the centrifugal pump, and one end of the bellows is sealed and fixedly installed with the inner wall of the pump body, and the pump body ring is installed at one end of the bellows close to the impeller ring, and the end face of the impeller ring can be in contact with the end face of the pump body ring;

[0008] A spring seat, fixedly arranged at one end of the bellows close to the impeller ring;

[0009] A spring is arranged in the pump body and sleeved on the outer periphery of the bellows. One end of the spring is connected to the spring seat, and the other end presses against the pump body.

[0010] Preferably, the pump body mouth ring is made of impregnated graphite, and the impeller mouth ring is made of modified nylon.

[0011] Preferably, the spring and the spring seat are made of the same material, and the spring and the spring seat are both made of austenitic stainless steel, or both are made of duplex stainless steel.

[0012] Preferably, the spring and the spring seat are made of one of 304 stainless steel, 316 stainless steel or 2205 stainless steel.

[0013] Preferably, the compression amount of the spring subjected to the axial force is L, L=F / k; wherein F is the axial force applied to the spring, and k is the elastic coefficient of the spring;

[0014] G is the shear elastic modulus of the material;

[0015] d is the spring wire diameter;

[0016] Dm is the center diameter of the spring;

[0017] Nc is the effective number of turns.

[0018] Preferably, the bellows is a rubber bellows.

[0019] Preferably, the rubber bellows includes a first fixing portion and a first corrugated portion connected to each other, and a first circular hole and a second circular hole are provided on the inner wall of the pump body, wherein the diameter of the first circular hole is larger than the inner diameter of the pump body, and the diameter of the first circular hole is larger than the diameter of the second circular hole;

[0020] The spring is located in the space between the first corrugated portion and the first circular hole, one end of the spring is connected to the spring seat, and the other end is pressed against the bottom of the first circular hole;

[0021] The first fixing portion is located in the second circular hole, and an end portion thereof is pressed against the bottom of the groove of the second circular hole;

[0022] The pump body mouth ring is installed at the end of the first corrugated part.

[0023] Preferably, the first fixing portion and the second circular hole are interference fitted.

[0024] Preferably, the impeller ring is fastened to the impeller by screws.

[0025] A centrifugal pump comprises the centrifugal pump impeller and the mouth ring sealing device.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] In the present invention, an impeller ring is mounted on the impeller, a bellows is mounted within the pump body, and a spring is positioned within the space between the bellows and the inner wall of the pump body. One end of the spring presses against the bottom of the first circular hole, and the other end is connected to the spring seat. When the centrifugal pump is stopped, the pump ring and the impeller ring are separated, and the spring is also relaxed. When the centrifugal pump is operating, an axial force is generated under the action of hydraulic pressure due to the asymmetric areas of the front and rear covers of the impeller. This axial force is directed toward the pump inlet. Under the action of this axial force, the rotor structure consisting of the impeller, impeller ring, etc. moves toward the inlet of the centrifugal pump, and the impeller ring is fixed to the impeller and rotates synchronously with the impeller. At this time, the end faces of the pump ring and the impeller ring fit together, and the spring is compressed and deformed by the axial force. At this time, the spring can balance the axial force of the above-mentioned rotor structure, and the remaining axial force is balanced by the thrust bearing. Because the pressure of the liquid at the outlet of the impeller is higher than the pressure of the liquid at the inlet, if a conventional mouth ring method is used, there will be a certain gap between the impeller mouth ring and the pump body mouth ring. The pressure difference between the inlet and the outlet causes part of the liquid passing through the impeller to flow back to the inlet from this gap, which is bound to increase the volume loss and reduce the efficiency, flow rate and head of the pump. One end of the bellows in the utility model is sealed and fixedly connected to the inner wall of the pump body, and the end face of the pump body mouth ring is in contact with the end face of the impeller mouth ring to separate the inlet and the extrusion chamber. The extrusion chamber forms an independent sealed cavity, and no liquid will flow back from the outlet to the inlet, thereby greatly improving the efficiency of the water pump.

[0028] The compression force generated by the spring fixed at the inlet of the pump body balances part of the axial force, thereby reducing the load of the thrust bearing and extending the service life of the thrust bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a cross-sectional view of a centrifugal pump in the prior art;

[0030] Figure 2 This is a cross-sectional view of the centrifugal pump in the present utility model (the end face of the pump body ring contacts the end face of the impeller ring);

[0031] Figure 3 This is a cross-sectional view of the centrifugal pump in the present utility model (the end face of the pump body mouth ring and the end face of the impeller mouth ring are separated);

[0032] Figure 4 This is a structural cross-sectional view of the centrifugal pump impeller and mouth ring sealing device in the utility model.

[0033] Among them, 1. impeller; 11. front cover; 12. rear cover; 2. impeller mouth ring; 3. pump body; 4. pump body mouth ring; 5. bellows; 51. first fixing part; 52. first corrugated part; 6. spring; 7. spring seat; 8. first circular hole; 9. second circular hole; 10. screw; 11. outlet; 15. thrust bearing. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0037] In the description of the present utility model, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the utility model product is usually placed when in use. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0038] It should also be noted that, in the description of this utility model, unless otherwise specified or limited, the terms "disposed" and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0039] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0040] The following describes in detail embodiments of the present invention. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0041] like Figure 2-Figure 4 As shown, this embodiment provides a centrifugal pump impeller and ring sealing device, comprising an impeller ring 2, a bellows 5, a pump body ring 4, a spring seat 7, and a spring 6. The impeller ring 2 is fixedly mounted on the impeller 1 of the centrifugal pump. The bellows 5 is coaxially arranged with the pump body 3 of the centrifugal pump, with one end of the bellows 5 sealed and fixed to the inner wall of the pump body 3. The pump body ring 4 is mounted on the end of the bellows 5 near the impeller ring 2. The spring seat 7 is fixedly mounted on the end of the bellows 5 near the impeller ring 2. The spring 6 is sleeved around the outer circumference of the bellows 5, with one end connected to the spring seat 7 and the other end pressing against the pump body 3. Specifically, a first circular hole 8 is provided on the inner wall of the pump body 3. The diameter of the first circular hole 8 is larger than the inner diameter of the pump body, and the other end of the spring 6 can press against the bottom of the groove of the first circular hole 8. Alternatively, a pressure ring can be provided inside the pump body 3, with the other end of the spring pressing against the pressure ring. When the centrifugal pump is working, the impeller mouth ring 2 moves axially toward the pump body mouth ring 4 , and the end surface of the impeller mouth ring 2 fits with the end surface of the pump body mouth ring 4 .

[0042] In this embodiment, an impeller ring 2 is mounted on the impeller 1, and a bellows 5 is installed within the pump body 3. A spring 6 is located in the space between the bellows 5 and the inner wall of the pump body 3. One end of the spring 6 presses against the bottom of the first circular hole 8, and the other end is connected to the spring seat 7. When the centrifugal pump is stopped, the pump ring 4 and the impeller ring 2 are separated, and the spring 6 is also in a relaxed state. When the centrifugal pump is operating, the asymmetric areas of the front cover 11 and rear cover 12 of the impeller 1 generate an axial force under the action of hydraulic pressure. This axial force is directed toward the pump inlet. Under the action of this axial force, the rotor structure composed of the impeller 1 and the impeller ring 2 moves toward the centrifugal pump inlet. The impeller ring 2 is fixed to the impeller 1 and rotates synchronously with the impeller 1. At this time, the end faces of the pump ring 4 and the impeller ring 2 are in contact, and the spring 6 is compressed and deformed by the axial force. At this time, the spring 6 can balance the axial force of the above-mentioned rotor structure, and the remaining axial force is balanced by the thrust bearing 15. Because the pressure of the liquid at the outlet 11 of the impeller 1 is higher than the pressure of the liquid at the inlet, if a conventional ring method is used, there will be a certain gap between the impeller ring 2 and the pump body ring 4. The pressure difference between the outlet 11 and the inlet causes a part of the liquid passing through the impeller 1 to flow back to the inlet from this gap, which is bound to increase the volume loss and reduce the efficiency, process and head of the pump. In this embodiment, one end of the bellows 5 is sealed and fixedly connected to the inner wall of the pump body 3, and the end face of the pump body ring 4 contacts the end face of the impeller ring 2 to separate the inlet and the extrusion chamber. The extrusion chamber is as shown in FIG. Figure 2 The area A shown by the red frame forms an independent sealed cavity, and no liquid will flow back from the outlet 11 to the inlet, thereby greatly improving the efficiency of the water pump.

[0043] The compression force generated by the spring 6 fixed at the inlet of the pump body 3 balances part of the axial force, thereby reducing the load of the thrust bearing 15 and extending the service life of the thrust bearing 15.

[0044] Preferably, the impeller ring 2 and the pump body ring 4 are made of different materials, or the impeller ring 2 and the pump body ring 4 are made of the same material but with different hardnesses, with the pump body ring 4 being made of impregnated graphite and the impeller ring 2 being made of modified nylon. Modified nylon is a granular product formed by modifying the physical properties of nylon raw materials, such as reinforced nylon, toughened nylon, wear-resistant nylon, halogen-free flame-retardant nylon, conductive nylon, and flame-retardant nylon. Optionally, the modified nylon material in this embodiment is a nylon material with at least one filler selected from graphite, molybdenum disulfide, and glass fiber added thereto. Modified nylon materials are known in the art, and the specific composition is not described in detail here.

[0045] The impeller ring 2 and the pump body ring 4 are made of different materials. When the impeller 1 rotates at high speed, it drives the impeller ring 2 to rotate synchronously at high speed. When the impeller ring 2 and the pump body ring 4 come into contact, they must be prevented from seizing and becoming unable to open. While the impeller ring 2 and the pump body ring 4 are made of the same material, their hardness differs. Conventional ring systems can cause ring seizures due to insufficient clearance or excessive rotor runout. This zero-leakage ring design also avoids this problem, reducing part processing difficulty.

[0046] Preferably, the spring 6 and spring seat 7 are made of the same material, maintaining consistency. Both the spring 6 and spring seat 7 are made of austenitic stainless steel or duplex stainless steel. The spring 6 and spring seat 7 are welded and fixedly connected. The same material facilitates welding. Further preferably, both the spring 6 and spring seat 7 are made of one of 304 stainless steel, 316 stainless steel, and 2205 stainless steel.

[0047] Preferably, the compression amount of the spring 6 subjected to the axial force is L, L=F / k, wherein F is the axial force applied to the spring 6, and k is the elastic coefficient of the spring 6;

[0048]

[0049] G is the shear elastic modulus of the material;

[0050] d is the spring wire diameter;

[0051] Dm is the center diameter of spring 6;

[0052] Nc is the effective number of turns;

[0053] Specifically, the spring 6 can balance 20%-50% of the axial force of the rotor component, reduce the friction loss of the thrust bearing 15, and extend the service life of the pump.

[0054] Preferably, the bellows 5 is a rubber bellows.

[0055] Preferably, the rubber bellows includes a first fixed portion 51 and a first corrugated portion 52 connected to each other, a second circular hole 9 is provided on the inner wall of the pump body 3, the first fixed portion 51 is provided in the first circular hole 8, the diameter of the second circular hole 9 is smaller than the diameter of the first circular hole 8, and larger than the inner diameter of the pump body, the spring 6 is located in the space between the first corrugated portion 52 and the first circular hole 8, one end of the spring 6 is connected to the spring seat 7, and the other end is pressed against the bottom of the groove of the first circular hole 8.

[0056] The first fixing portion 51 of the rubber bellows is fixedly installed at the bottom of the groove of the second circular hole 9 to prevent the bellows 5 from moving axially. At the same time, the spring 6 is located in the space between the first corrugated portion 52 and the first circular hole 8. When the spring 6 expands and contracts, the first corrugated portion 52 expands and contracts synchronously with the spring 6.

[0057] Preferably, the first fixing portion 51 and the second circular hole 9 are interference fitted to ensure that no leakage occurs therebetween.

[0058] Preferably, glue is applied between the first fixing portion 51 and the second circular hole 9 to ensure a tight connection between the two.

[0059] Preferably, the impeller ring 2 is fastened to the impeller 1 by screws 10 , and the impeller 1 and the impeller ring 2 are transitionally fitted to facilitate the removal and replacement of the impeller ring 2 .

[0060] Preferably, the impeller ring 2 is fastened to the impeller 1 by two screws 10 , and the two screws 10 are evenly distributed along the circumference of the impeller 1 .

[0061] In other optional embodiments, the bellows 5 may be a metal bellows, with an O-ring seal disposed between the metal bellows and the inner wall of the pump body 3. Specifically, the metal bellows includes a second fixed portion and a second corrugated portion that are connected to each other. The second fixed portion is mounted within the second circular hole 9, with its end abutting against the bottom of the groove of the second circular hole 9. The spring 6 is located in the space between the second corrugated portion and the first circular hole 8, and the pump body mouth ring 4 is mounted at the end of the second corrugated portion.

[0062] In this embodiment, a centrifugal pump is also provided, including the centrifugal pump impeller and the mouth ring sealing device. The centrifugal pump impeller and the mouth ring sealing device are used to improve the efficiency and head of the water pump, and the rated flow rate is less than 10m 3 / h or multi-stage centrifugal pumps have a particularly significant effect in improving efficiency.

[0063] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. A person skilled in the art will be able to make other variations or modifications based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A centrifugal pump impeller and ring sealing device, characterized in that: It comprises an impeller mouth ring (2) which is fixedly mounted on an impeller (1) of a centrifugal pump; A bellows (5) and a pump body mouth ring (4), wherein the bellows (5) is coaxially arranged with the pump body (3) of the centrifugal pump, and one end of the bellows (5) is fixedly and sealedly mounted on the inner wall of the pump body (3); the pump body mouth ring (4) is mounted on one end of the bellows (5) close to the impeller mouth ring (2), and the end face of the impeller mouth ring (2) can be fitted with the end face of the pump body mouth ring (4); A spring seat (7) is fixedly arranged on one end of the bellows (5) close to the impeller ring (2); A spring (6) is arranged in the pump body (3) and sleeved on the outer periphery of the bellows (5); one end of the spring (6) is connected to the spring seat (7), and the other end presses against the pump body (3).

2. The centrifugal pump impeller and mouth ring sealing device according to claim 1, characterized in that: The pump body mouth ring (4) is made of impregnated graphite, and the impeller mouth ring (2) is made of modified nylon.

3. The centrifugal pump impeller and mouth ring sealing device according to claim 2, characterized in that: The spring (6) and the spring seat (7) are made of the same material, and the spring (6) and the spring seat (7) are both made of austenitic stainless steel, or both of duplex stainless steel.

4. The centrifugal pump impeller and mouth ring sealing device according to claim 3, characterized in that: The material of the spring (6) and the spring seat (7) is one of 304 stainless steel, 316 stainless steel or 2205 stainless steel.

5. The centrifugal pump impeller and mouth ring sealing device according to claim 4, characterized in that: The compression amount of the spring (6) subjected to the axial force is L, L=F / k; wherein F is the axial force applied to the spring (6), k is the elastic coefficient of the spring (6), G is the shear elastic modulus of the material; d is the wire diameter of the spring (6); Dm is the center diameter of the spring (6); Nc is the effective number of turns.

6. The centrifugal pump impeller and mouth ring sealing device according to any one of claims 1 to 5, characterized in that: The bellows (5) is a rubber bellows.

7. The centrifugal pump impeller and ring sealing device according to claim 6, characterized in that: The rubber bellows comprises a first fixing portion (51) and a first corrugated portion (52) connected to each other, a first circular hole (8) and a second circular hole (9) are provided on the inner wall of the pump body (3), the diameter of the first circular hole (8) being larger than the inner diameter of the pump body, and the diameter of the first circular hole being larger than the diameter of the second circular hole (9); The spring (6) is located in the space between the first corrugated portion (52) and the first circular hole (8), one end of the spring (6) is connected to the spring seat (7), and the other end is pressed against the bottom of the groove of the first circular hole (8); The first fixing portion (51) is located in the second circular hole (9), and its end portion is pressed against the bottom of the groove of the second circular hole (9); The pump body mouth ring (4) is installed at the end of the first corrugated portion (52).

8. The centrifugal pump impeller and ring sealing device according to claim 7, characterized in that: The first fixing portion (51) and the second circular hole (9) are interference fitted.

9. The centrifugal pump impeller and ring sealing device according to claim 8, characterized in that: The impeller mouth ring (2) is fastened to the impeller (1) via screws (10).

10. A centrifugal pump, characterized in that: The invention comprises a centrifugal pump impeller and a mouth ring sealing device according to any one of claims 1 to 9.

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