Centrifugal pump impeller capable of wide-range operation

Abstract

The application provides a centrifugal pump impeller capable of wide-range operation, comprising a front cover plate and a rear cover plate, and a plurality of blades are arranged between the front cover plate and the rear cover plate; characterized in that at least one blade is a rotatable blade, the rotatable blade is provided with index plates at two ends respectively, the index plates at the two ends are respectively clamped on the front cover plate and the rear cover plate through fixing clamps, and the index plates at different positions are clamped through the fixing clamps, so as to change the angle of the rotatable blade. The application changes the angle of the rotatable blade, improves the operation range of the centrifugal pump, and reduces the cost of replacing the impeller.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fluid machinery, in particular to a centrifugal pump impeller capable of wide-range operation. BACKGROUND

[0002] A pump is a machine that transports fluid or pressurizes fluid. It transmits mechanical energy or other external energy to the liquid, so that the liquid energy increases. Pumps are mainly used to transport liquids such as water, oil, acid and alkali liquid, emulsion, suspension emulsion and liquid metal, and can also transport liquid-gas mixtures and liquids containing suspended solid objects. According to the size of the specific speed, the pump is divided into centrifugal pumps, mixed flow pumps and axial (through) flow pumps. The hydraulic performance of the centrifugal pump impeller is determined after design. The blades are damaged after a short time of operation due to cavitation and other reasons, and the cost of replacing the new impeller is high, and the disassembly is complicated. In view of this problem, the present application provides a wide-range operation centrifugal pump impeller, which has the functions of quick disassembly and adjustable angle of the blades, greatly expanding the operating condition range of the centrifugal pump.

[0003] Two patents in the prior art are: ZL201710354187.9 blade-adjustable centrifugal pump or fan impeller, and ZL202110369048.X centrifugal pump impeller with adjustable blade outlet angle. Both of the two patents use deformed blades, the former fixes the position of the blade near the outlet edge, and the latter fixes the position of the blade near the inlet edge, and realizes the change of the blade angle by bending and twisting the blade. The problems of the two are:

[0004] (1) only small-angle adjustment of local blades, the range of centrifugal pump operating conditions is limited;

[0005] (2) the blades are usually made of metal, and frequent bending and twisting of the blades can easily lead to fatigue fracture;

[0006] (3) the blade adjustment method is complicated, and the blade cannot be quickly adjusted and replaced. SUMMARY

[0007] In view of the deficiencies in the prior art, the present application provides a centrifugal pump impeller capable of wide-range operation, which changes the angle of the rotatable blades, improves the operating range of the centrifugal pump, and reduces the cost of replacing the impeller.

[0008] The present application achieves the above technical purposes through the following technical means.

[0009] The centrifugal pump impeller with wide operation range comprises a front cover plate and a rear cover plate, and a plurality of blades are arranged between the front cover plate and the rear cover plate; at least one blade is a rotatable blade, and a dividing disc is arranged at each end of the rotatable blade and is fixed on the front cover plate and the rear cover plate; the dividing discs at the two ends are clamped on the front cover plate and the rear cover plate through fixing clamps; the dividing discs at different positions are clamped through the fixing clamps, so as to change the angle of the rotatable blade.

[0010] Further, the front cover plate and the rear cover plate are provided with open T-shaped stepped clamping grooves, and the dividing discs are clamped on the stepped clamping grooves through the fixing clamps.

[0011] Further, the rotatable blade is provided with a rotating shaft at each end, and a dividing disc is arranged on the rotating shaft; a plurality of dividing grooves are uniformly arranged on the dividing disc, and one of the dividing grooves is connected with a fixing clamp.

[0012] Further, the fixing clamp comprises an upper clamp plate and a lower clamp plate; a first arc-shaped groove is arranged at one end of the upper clamp plate, and a convex arc-shaped dividing positioning key is arranged in the first arc-shaped groove, so as to position the dividing disc; the lower clamp plate is arranged below the upper clamp plate, one end of the lower clamp plate protrudes from the first arc-shaped groove, and the upper clamp plate and the lower clamp plate form a T-shaped clamp, which is matched with the stepped clamping groove.

[0013] Further, one end of the lower clamp plate protruding from the first arc-shaped groove is provided with a second arc-shaped groove, and the second arc-shaped groove is used for supporting the rotating shaft.

[0014] Further, the blade types of the plurality of rotatable blades are the same or different, and the blade types of the rotatable blades are straight blades, forward-curved blades or backward-curved blades.

[0015] Further, a trajectory formed by one rotation of the rotatable blade does not exceed the intersection of a straight line and an arc on the rear cover plate, and does not exceed the outlet edge of the impeller; the inlet edge and the outlet edge of the rotatable blade are both chamfered.

[0016] Further, the contour size of the T-shaped clamp is matched with the contour size of the stepped clamping groove, so that the T-shaped clamp is completely embedded in the front cover plate or the rear cover plate.

[0017] A centrifugal pump comprises the centrifugal pump impeller with wide operation range.

[0018] The centrifugal pump impeller with wide operation range has the following advantages:

[0019] 1. The centrifugal pump impeller with wide operation range can adjust the blades by rotating the dividing disc, so that the angle of the blades can be adjusted at will, the water pump hydraulic performance and operation condition are adjusted, and the operation range of the centrifugal pump is greatly widened.

[0020] 2. The centrifugal pump impeller capable of wide-range operation according to the present application can improve local loss and pressure pulsation of the centrifugal pump, improve operation stability, and realize stability adjustment of the centrifugal pump by adjusting the angle of the single or multiple rotatable blades.

[0021] 3. The centrifugal pump impeller capable of wide-range operation according to the present application is convenient for blade replacement. After the pump is operated for a certain period of time, the blade is abraded and cavitation erosion occurs, which causes the performance of the water pump to be greatly reduced. Only the pump cover and the fixed card are disassembled, and the new rotatable blade is replaced, which reduces the maintenance cost and improves the maintenance efficiency.

[0022] 4. The centrifugal pump impeller capable of wide-range operation according to the present application has a number of rotatable blades, which is usually 3-9. One or more of the rotatable blades can be straight blades, forward-curved blades or backward-curved blades, which widens the limitation of the single-form blade impeller and further widens the application occasion in the actual engineering application to meet the demand of various working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. The drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0024] Figure 1 FIG. 1 is a schematic diagram of the centrifugal pump impeller capable of wide-range operation according to the present application.

[0025] Figure 2 FIG. 2 is an A-A sectional view of the centrifugal pump impeller capable of wide-range operation according to the present application. Figure 1

[0026] Figure 3 FIG. 4 is a three-dimensional view of the front cover plate and the rear cover plate according to the present application.

[0027] Figure 4 FIG. 5 is an assembly view of the rotatable blade and the index plate according to the present application.

[0028] Figure 5 FIG. 6 is an axial view of the fixed card according to the present application.

[0029] Figure 6 FIG. 7 is a front view and a top view of the fixed card according to the present application.

[0030] Figure 7 FIG. 8 is a schematic diagram of blade angle transformation provided by the embodiment of the present application.

[0031] In the drawings:

[0032] ​1 - front cover plate; 11 - stepped clamping groove; 2 - fixed clamping plate; 21 - mounting hole; 22 - index positioning key; 23 - lower clamping plate; 24 - upper clamping plate; 3 - index disc; 4 - rotatable blade; 5 - rear cover plate; 6 - rotating shaft; 7 - fixing screw. DETAILED DESCRIPTION

[0033] Embodiments of the present application are described in detail below with reference to examples illustrated in the accompanying drawings, in which the same or similar components have the same or similar designations throughout the various figures. The embodiments described below are examples for explaining the present application and are not intended to be limiting of the present application.

[0034] In the description of the present application, it is to be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "axial", "radial", "vertical", "horizontal", "inner", "outer", and the like are based on the orientations or positional relationships shown in the drawings, and are merely intended to facilitate the description of the present application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0035] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0036] As Figure 1 and Figure 2As shown, the wide-range operating centrifugal pump impeller of the present application comprises a front cover plate 1 and a rear cover plate 5, and a plurality of blades are arranged between the front cover plate 1 and the rear cover plate 5; at least one blade is a rotatable blade 4, and the rotatable blade 4 is provided with a dividing disc 3 at each end and the dividing disc 3 is installed on the front cover plate 1 and the rear cover plate 5; the dividing disc 3 at each end is clamped on the front cover plate 1 and the rear cover plate 5 through a fixed clamping piece 2; the fixed clamping piece 2 clamps the dividing disc 3 at different positions to change the angle of the rotatable blade 4. By disassembling the fixed clamping piece 2 and changing the angle of the dividing disc 3, the blade angle can be adjusted arbitrarily, and the purpose of adjusting the working condition of the water pump is achieved.

[0037] As shown in the drawings, Figure 3 The front cover plate 1 and the rear cover plate 5 are provided with an open T-shaped stepped clamping groove 11, and the dividing disc 3 is clamped on the stepped clamping groove 11 through the fixed clamping piece 2. The fixed clamping piece 2 is installed in the threaded hole of the T-shaped stepped clamping groove 11 through a fixing screw 7. The open T-shaped stepped clamping groove 11 can facilitate the quick disassembly of the fixed clamping piece 2 and the adjustment of the angle of the rotatable blade 4.

[0038] As shown in the drawings, Figure 4 The rotatable blade 4 is provided with a dividing disc 3 at each end through a rotating shaft 6, the dividing disc 3 is provided with a plurality of dividing grooves distributed along the circumferential direction, and one of the dividing grooves is connected with the fixed clamping piece 2. The outer diameter of the rotating shaft 6 is smaller than the root of the dividing groove to prevent mutual interference and meet the strength requirement. In the embodiment, in order to achieve the purpose of dividing the angle of the blade rotation, the angle is divided by 18° every time, and then 20 dividing groove positions are arranged at 18°, 36°, 54°, …, 342°. In actual engineering application, the angle can be divided according to the needs, that is, the angle adjustment accuracy is changed by increasing or reducing the number of dividing grooves, so as to realize the working condition adjustment accuracy.

[0039] As shown in the drawings, Figure 5 and Figure 6 The fixed clamping piece 2 comprises an upper clamping plate 24 and a lower clamping plate 23, one end of the upper clamping plate 24 is provided with a first arc-shaped groove, the first arc-shaped groove is provided with a convex arc surface dividing positioning key 22 for positioning the dividing disc 3, the lower clamping plate 23 is located below the upper clamping plate 24, one end of the lower clamping plate 23 protrudes out of the first arc-shaped groove, and the upper clamping plate 24 and the lower clamping plate 23 form a T-shaped clamping piece which is matched with the stepped clamping groove 11. The contour size of the T-shaped clamping piece is matched with the contour size of the stepped clamping groove 11, so that the T-shaped clamping piece is completely embedded in the front cover plate 1 or the rear cover plate 5. As can be seen from the drawings, the step height of the T-shaped clamping piece is consistent with the depth of the stepped clamping groove 11, so that the fixed clamping piece 2 does not protrude from the front cover plate or the rear cover plate, and the hydraulic loss is reduced. One end of the lower clamping plate 23 protruding out of the first arc-shaped groove is provided with a second arc-shaped groove, and the second arc-shaped groove is used to support the rotating shaft 6 together with the stepped clamping groove 11.

[0040] The rotatable blades 4 can be straight, forward-curved, or backward-curved, with 3-9 blades located between the front cover plate 1 and the rear cover plate 5. When multiple rotatable blades 4 are installed on the impeller, any one or all of them can be replaced with straight, forward-curved, or backward-curved blades to meet actual operating requirements. The trajectory formed by one rotation of the rotatable blade 4 must not exceed the intersection of the straight line and the arc on the rear cover plate 5, and must not exceed the impeller outlet edge. Both the inlet and outlet edges of the rotatable blade 4 are rounded to ensure a stable fluid transition and reduce hydraulic losses.

[0041] With multiple rotatable blades 4, the angle of any one or all of the rotatable blades 4 can be adjusted to meet actual needs. After a certain period of operation, when the impeller needs to be replaced due to wear, cavitation, etc., it is only necessary to remove the pump cover and fixing clip 2 and replace the new rotatable blades 4.

[0042] Rotatable blade 4 is installed between front cover plate 1 and rear cover plate 5. Stepped grooves 11 are provided on both front and rear cover plates 1 and 5, which cooperate with the indexing plate 3 to press the rotatable blade 4, limiting axial displacement. The height of the stepped groove 11 is consistent with that of the fixing card 2, achieving flow channel filling. Non-through mounting holes 21 are provided on the stepped groove 11. Fixing screws 7 install the fixing card 2 on the front cover plate 1 or rear cover plate 5, which can constrain the radial movement of the rotatable blade 4 and reduce hydraulic loss.

[0043] With multiple rotatable blades 4, the angle of any one or all of the rotatable blades 4 can be adjusted to meet actual needs. Alternatively, any one or all of the rotatable blades 4 can be replaced with one of the following forms: straight blades, forward-curved blades, backward-curved blades, etc., to meet the requirements of actual working conditions.

[0044] like Figure 7 As shown, taking a centrifugal pump impeller as an example, the calculation is performed for a flow rate of 400 m³ / h. 3 / h, rotational speed 1450rpm, outer diameter 268mm, blade outlet angle designed 20 degrees, volumetric loss, hydraulic loss, etc. estimated coefficients 0.9, assuming no pre-swirl at the inlet, calculate H = U²V according to the pump head formula. u2 / g, yielding a theoretical pump head of 24.8m. If the blades are rotated to achieve a 60-degree outlet angle, the theoretical pump head is 32.5m; if the blades are rotated to achieve a 10-degree outlet angle, the theoretical pump head is 12.5m. Furthermore, the blade rotation angle can be from 0 to 360 degrees, i.e., any circumferential rotation angle, achieving a wider operating range. Therefore, the centrifugal pump impeller of this invention, capable of wide-range operation, can change the head according to load requirements. For example, if a high head is required, the blades will be rotated to achieve a 60-degree outlet angle; if a low head is required, the blades will be rotated to achieve a 10-degree outlet angle.

[0045] The centrifugal pump comprises the wide-range operating centrifugal pump impeller.

[0046] It should be understood that, although the present specification is described in terms of various embodiments, not every embodiment contains only one independent technical solution, and the specification is described in this way only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

[0047] The series of detailed descriptions listed above are only specific descriptions of the feasible embodiments of the present application, and are not used to limit the protection scope of the present application, and equivalent embodiments or changes made without departing from the spirit of the present application should be included in the protection scope of the present application.

Claims

1. A centrifugal pump impeller capable of wide-range operation, comprising a front cover plate (1) and a rear cover plate (5), a plurality of blades being arranged between the front cover plate (1) and the rear cover plate (5); characterized in that, At least one of the blades is a rotatable blade (4), and the rotatable blade (4) is provided with a dividing disc (3) at each end, which is installed on a front cover plate (1) and a rear cover plate (5); the dividing disc (3) at each end is clamped on the front cover plate (1) and the rear cover plate (5) through a fixed card (2); the fixed card (2) clamps the dividing disc (3) at different positions to change the angle of the rotatable blade (4); The front cover plate (1) and the rear cover plate (5) are provided with an open T-shaped stepped clamping groove (11), and the dividing disc (3) is clamped on the stepped clamping groove (11) through the fixed card (2); The rotatable blade (4) is provided with a dividing disc (3) at each end through a rotating shaft (6), and the dividing disc (3) is uniformly provided with a plurality of dividing grooves, one of which is connected with the fixed card (2); The fixed card (2) comprises an upper clamping plate (24) and a lower clamping plate (23), one end of the upper clamping plate (24) is provided with a first arc-shaped groove, and the first arc-shaped groove is provided with a convex arc surface dividing positioning key (22) for positioning the dividing disc (3); the lower clamping plate (23) is located below the upper clamping plate (24), one end of the lower clamping plate (23) protrudes from the first arc-shaped groove, and the upper clamping plate (24) and the lower clamping plate (23) form a T-shaped card which is matched with the stepped clamping groove (11).

2. The wide-range operable centrifugal pump impeller according to claim 1, characterized in that, One end of the lower clamping plate (23) protruding from the first arc-shaped groove is provided with a second arc-shaped groove, and the second arc-shaped groove is used for supporting the rotating shaft (6).

3. The wide-range operable centrifugal pump impeller according to claim 1, characterized in that, The plurality of rotatable blades (4) have the same or different blade shapes, and the rotatable blades (4) are straight blades, forward-curved blades or backward-curved blades.

4. The wide-range operable centrifugal pump impeller according to claim 1, characterized in that, The trajectory formed by one rotation of the rotatable blade (4) does not exceed the outlet edge of the impeller, and the inlet edge and the outlet edge of the rotatable blade (4) are both rounded.

5. The wide-range operable centrifugal pump impeller according to claim 1, characterized in that, The contour size of the T-shaped card matches the contour size of the stepped clamping groove (11), so that the T-shaped card is completely embedded in the front cover plate (1) or the rear cover plate (5).

6. A centrifugal pump characterized by The centrifugal pump impeller capable of wide-range operation according to any one of claims 1-5.

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