CN116221128A - Closed impeller slurry pump with controllable flexible blades - Google Patents
Closed impeller slurry pump with controllable flexible blades Download PDFInfo
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- CN116221128A CN116221128A CN202310261346.6A CN202310261346A CN116221128A CN 116221128 A CN116221128 A CN 116221128A CN 202310261346 A CN202310261346 A CN 202310261346A CN 116221128 A CN116221128 A CN 116221128A
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- Prior art keywords
- impeller
- cover plate
- pump
- flexible blades
- pump shaft
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D7/00—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts
- F04D7/02—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts of centrifugal type
- F04D7/04—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts of centrifugal type the fluids being viscous or non-homogenous
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
- F04D15/0055—Rotors with adjustable blades
- F04D15/0061—Rotors with adjustable blades responsive to temperature
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/18—Rotors
- F04D29/22—Rotors specially for centrifugal pumps
- F04D29/2205—Conventional flow pattern
- F04D29/2222—Construction and assembly
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/18—Rotors
- F04D29/22—Rotors specially for centrifugal pumps
- F04D29/24—Vanes
- F04D29/247—Vanes elastic or self-adjusting
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/58—Cooling; Heating; Diminishing heat transfer
- F04D29/586—Cooling; Heating; Diminishing heat transfer specially adapted for liquid pumps
- F04D29/588—Cooling; Heating; Diminishing heat transfer specially adapted for liquid pumps cooling or heating the machine
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a closed impeller slurry pump with controllable flexible blades, which comprises: the pump body is internally provided with a pump shaft, the front end of the pump shaft is provided with a front cover plate, and the rear end of the pump shaft is provided with a rear cover plate; the impeller is an integrally cast metal piece, is arranged on the pump shaft through a hub and limited by a shaft end nut, and is matched with the front cover plate and the rear cover plate to form an overcurrent medium flow channel, a plurality of blades are uniformly distributed on the impeller, and each blade comprises front cast iron, rear flexible blades and a memory alloy strip. In the invention, the front half section of the blade is combined with the hub to ensure rigidity so as to facilitate acting on fluid entering the impeller, the rigidity of the rear half section of the blade can be adjusted through the memory alloy, impellers with different wrap angles and setting angles are formed for different concentrations of overcurrent media, and the operation efficiency of the slurry pump under different concentrations of overcurrent media is improved.
Description
Technical Field
The invention relates to the technical field of slurry pumps, in particular to a closed impeller slurry pump with controllable flexible blades.
Background
The slurry pump is an important industrial production fluid conveying device, has wide application in power plants, building material industry, metallurgy industry and paper industry, and particularly in the paper industry, the slurry pump is taken as a power device to account for more than 90% of the total number of pumps in the paper mill. The flowing medium of the slurry pump mainly comprises a solid-liquid two-phase flow medium and also comprises fiber suspension flow, and the size of solid phase particles is from nano level to macro level and the concentration is from extremely thin to high concentration, so that the flowing medium generates different rheological behaviors, wherein the non-Newtonian fluid mechanical property is a very representative property. The non-newtonian fluid mechanical property refers to that the viscosity of fluid and the change of the relative speed of flow motion are in a nonlinear relation, and the change is expressed on a slurry pump, so that the torque carried by an impeller of the slurry pump is different when the slurry pump conveys slurries with different concentrations.
In addition, in order to ensure the passing performance of the slurry, the existing slurry pump products often adopt an open impeller or a semi-open impeller, but the improvement of the pump efficiency is greatly limited due to the difference in the form of the blades compared with a closed impeller.
Disclosure of Invention
In order to solve the technical problems in the background technology, the invention designs the closed impeller slurry pump with the controllable flexible blades, and the rigidity of the closed impeller slurry pump can be actively regulated through temperature change according to the change of flow and fluid medium properties so as to adapt to the fluid flow state, realize the function of efficient transportation, improve the working efficiency of the slurry pump and reduce the starting load of a motor.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
a closed impeller slurry pump with controllable flexible blades, comprising:
the pump body is internally provided with a pump shaft, the front end of the pump shaft is provided with a front cover plate, and the rear end of the pump shaft is provided with a rear cover plate;
the impeller is an integrally cast metal piece, is arranged on the pump shaft through a hub and limited by a shaft end nut, and is matched with the front cover plate and the rear cover plate to form an overcurrent medium flow channel, a plurality of blades are uniformly distributed on the impeller, and the blades comprise cast iron, memory alloy strips and flexible blades;
and the heating device is used for heating the pump shaft, transmitting heat to the memory alloy strip through the pump shaft, and performing feedback adjustment according to the temperature of the memory alloy strip so as to control the rigidity of the blade.
In the invention, the front half section of the blade is combined with the hub to ensure rigidity so as to facilitate acting on fluid entering the impeller, the rigidity of the rear half section of the blade can be adjusted through the memory alloy, impellers with different wrap angles and setting angles are formed for different concentrations of overcurrent media, and the operation efficiency of the slurry pump under different concentrations of overcurrent media is improved.
As a further description of the above technical solution:
the heating device comprises an infrared thermal probe, an electromagnetic coil and a controller, wherein the electromagnetic coil is wound on the pump shaft, and the infrared thermal probe and the controller are arranged on the rear cover plate.
As a further description of the above technical solution:
the infrared thermal probe is used for detecting the temperature of the impeller and transmitting a temperature signal to the controller so as to adjust the heating temperature of the electromagnetic coil.
As a further description of the above technical solution:
the flexible blade is internally wrapped with a plurality of memory alloy strips, and the cast iron and the flexible blade are bonded through an adhesive. Considering that the manufacturing cost of the memory alloy is high and the fatigue failure risk exists, the flexible part of the impeller adopts a mode of wrapping the memory alloy by hard rubber, and is in bonding connection with the metal part of the impeller, so that the consumption of the memory alloy is obviously reduced while the performance is ensured, and meanwhile, the performance of the impeller can be ensured by only replacing the memory alloy when the performance of the memory alloy changes.
As a further description of the above technical solution:
the impeller is provided with a plurality of balance holes.
As a further description of the above technical solution:
a plurality of round holes are circumferentially distributed in the front cover plate, second magnets are placed in the round holes, and first magnets which form magnetic attraction with the second magnets are arranged at corresponding positions on the pump body. The impeller front cover plate adopts a magnetic attraction type fixing mode, the installation is convenient, the structure is simple, the back cover plate is provided with a labyrinth sealing structure, and the volume loss of the slurry pump is reduced.
As a further description of the above technical solution:
the matching position of the impeller and the rear cover plate is provided with a labyrinth seal groove, and the matching position of the rear cover plate, the pump body and the pump shaft is provided with a mechanical seal and is positioned through a seal cover. The mechanical seal is provided with a special mechanical seal cover, so that the mechanical seal replacement step is simplified.
In summary, due to the adoption of the technical scheme, the beneficial effects of the invention are as follows:
1. in the invention, the front half section of the blade is combined with the hub to ensure rigidity so as to facilitate acting on fluid entering the impeller, the rigidity of the rear half section of the blade can be adjusted through the memory alloy, impellers with different wrap angles and setting angles are formed for different concentrations of overcurrent media, and the operation efficiency of the slurry pump under different concentrations of overcurrent media is improved.
2. According to the invention, the pump shaft is heated by an electromagnetic induction principle, heat is transferred to the impeller along the pump shaft and finally transferred to the nickel-titanium memory alloy strip to control the rigidity of the impeller, the infrared thermal probe monitors the temperature of the impeller, so that the accurate control of the rigidity of the blade is realized, the temperature is accurately controlled by the infrared thermal probe and the temperature control algorithm which are equipped with the temperature-rising electromagnetic induction coil, and the rigidity of the blade is ensured to meet the expected requirement.
3. In the invention, the flexible part of the impeller is bonded and connected with the metal part of the impeller by adopting a mode of wrapping the memory alloy with hard rubber in consideration of high manufacturing cost and fatigue failure risk of the memory alloy, so that the consumption of the memory alloy is obviously reduced while the performance is ensured, and meanwhile, the performance of the impeller can be ensured by only replacing the memory alloy when the performance of the memory alloy is changed.
4. In the invention, the impeller, the front cover plate and the rear cover plate are combined together to form a runner similar to a closed impeller, so that the hydraulic performance of the slurry pump is improved.
Drawings
FIG. 1 illustrates a schematic cross-sectional view of a closed impeller slurry pump with controllable flexible blades provided in accordance with an embodiment of the present invention;
FIG. 2 illustrates a schematic impeller construction of a closed impeller slurry pump with controllable flexible blades according to an embodiment of the present invention;
FIG. 3 illustrates a schematic view of a vane configuration of a closed impeller slurry pump with controllable flexible vanes according to an embodiment of the present invention;
FIG. 4 illustrates a schematic cross-sectional view of a back cover plate of a closed impeller slurry pump with controllable flexible blades provided in accordance with an embodiment of the invention;
FIG. 5 illustrates a schematic structural view of a front cover plate of a closed impeller slurry pump with controllable flexible blades provided in accordance with an embodiment of the present invention;
fig. 6 shows a schematic perspective view of a closed impeller slurry pump with controllable flexible blades according to an embodiment of the invention.
Legend description:
1. a pump body; 11. a first magnet; 2. an impeller; 21. cast iron; 22. a memory alloy; 23. a flexible blade; 24. a hub; 25. a balance hole; 3. a pump shaft; 31. a shaft end nut; 4. a front cover plate; 41. a second magnet; 5. a back cover plate; 51. sealing cover; 52. labyrinth seal grooves; 6. mechanical sealing; 71. an infrared thermal probe; 72. an electromagnetic coil; 73. and a controller.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
Referring to fig. 1-6, the present invention provides a technical solution: a closed impeller slurry pump with controllable flexible blades, comprising:
the pump body 1, as shown in fig. 1, a pump shaft 3 is installed in the pump body, the pump shaft 3 is a main motor torque input part and is connected with a motor through a flat key, a front cover plate 4 is distributed at the front end of the pump shaft 3, a rear cover plate 5 is distributed at the rear end of the pump shaft 3, a plurality of round holes are circumferentially distributed on the front cover plate 4, a second magnet 41 is placed in the round holes, a first magnet 11 which forms magnetic attraction with the second magnet 41 is arranged at a corresponding position on the pump body 1, the front cover plate 4 is ensured to be axially fixed, a boss structure is arranged in the middle section of the front cover plate 4 and is used for installing and matching between the front cover plate 4 and the pump body 1, the radial position of the front cover plate 4 is ensured, the rear cover plate 5 and the pump body 1 are connected through bolts, matching is formed between the front cover plate and the impeller 2, the front cover plate is ensured to be close to a closed impeller, a labyrinth seal groove 52 is arranged at the matching position of the impeller 2 and the rear cover plate 5, the leakage amount of an overcurrent medium is reduced, the integral efficiency of pump equipment is improved, the rear cover plate 5 and the pump body 1 and the pump shaft 3 are matched position is provided with a mechanical seal 6, and the seal 51 is positioned through the seal cover 51, the seal 51 is installed on the rear cover plate 5 and used for positioning the mechanical seal 6, and the seal 51 is independently used for overhauling the mechanical seal 6 when the seal 51 is detached and can be independently overhauled;
the impeller 2, as shown in fig. 2 and 3, is an integrally cast metal piece, it is installed on pump shaft 3 through the hub 24 and limited through the axle end nut 31, form the flow medium runner of excess flow between the impeller 2 and front cover plate 4 and back cover plate 5, its form is consistent with closed impeller, seven blades are evenly distributed on the impeller 2, the blade includes front cast iron 21, nickel-titanium memory alloy strip 22 and back flexible blade 23, the rigidity of the front half of the blade is guaranteed to cast iron 21, offer energy for fluid just entering impeller 2, the flexible blade 23 is made of hard rubber, the rigidity of nickel-titanium memory alloy strip 22 has certain adjustability, flexible blade 23 is wrapped up with several memory alloy strips 22 inside, glue between the cast iron 21 and flexible blade 23 through the adhesive, there are multiple balancing holes 25 on the impeller 2, in order to reduce the axial force of impeller 2, concretely, the front half of the blade is combined with hub 24 to guarantee rigidity, in order to do work to fluid entering impeller 2, the back half of the blade can be adjusted through memory alloy strip 22, for the excess flow medium of different concentration, form different wrap angles and place the impeller 2 form different flow medium pump modes under different concentration;
the heating device, as shown in fig. 1, is used for heating the pump shaft 3, transmitting heat to the memory alloy strip 22 through the pump shaft 3, and performing feedback adjustment according to the temperature of the memory alloy strip 22 to control the rigidity of the blade, the heating device comprises an infrared heat sensing probe 71, an electromagnetic coil 72 and a controller 73, the electromagnetic coil 72 is wound on the pump shaft 3, the infrared heat sensing probe 71 and the controller 73 are installed on the back cover plate 5, the controller 73 controls the electromagnetic coil 72 to adjust the temperature thereof, the pump shaft 3 is heated by the electromagnetic induction principle, the heat is transmitted to the impeller 2 along the pump shaft 3, and finally transmitted to the nickel-titanium memory alloy strip 22 to control the rigidity thereof, the infrared heat sensing probe 71 monitors the temperature of the impeller 2, thereby realizing the accurate control of the rigidity of the blade, and particularly, the temperature rising electromagnetic induction coil is provided with an infrared sensor and a temperature control algorithm to realize the accurate control of the temperature, so as to ensure the rigidity of the blade to meet the expected requirement, wherein the electromagnetic induction heating control and the feedback control thereof are all known techniques of those skilled in the art, and the details are omitted.
In the invention, during installation, the position of the pump body 1 is fixed, the first magnet 11 is installed in a groove of the pump body, the second magnet 41 is installed in a round hole of the front cover plate 4, then the installed front cover plate 4 is installed on the pump body 1, and the installation of the front cover plate 4 is completed after the second magnet 41 is firmly absorbed. Next, the flexible blades 23 are mounted to the memory alloy strip 22 to form the complete impeller 2, the impeller 2 is secured to the pump shaft 3, and the shaft end nuts 31 are used for securing. Next, the seal cover 51 is bolted to the back cover plate 5 to form a combined pump body back cover plate 5, then the mechanical seal 6 is mounted to the pump shaft 3 from the other end of the pump shaft 3, and then the back cover plate 5 is mounted, and positioning is performed by the impeller 2 and the mechanical seal 6. And finally, the rear cover plate 5, the pump shaft 3 and the impeller 2 are mounted on the pump body 1 together, and are connected by bolts, so that the mounting is completed.
Working principle: when the slurry pump is used, in the working process of the slurry pump, the motor drives the impeller 2 to rotate through the pump shaft 3 to apply work to a conveying medium so as to push the conveying of the slurry, wherein the pump shaft 3 is heated through an electromagnetic induction principle, heat is transmitted to the impeller 2 along the pump shaft 3 and finally transmitted to the nickel-titanium memory alloy strip 22 so as to control the rigidity of the nickel-titanium memory alloy strip, the infrared thermal probe 71 monitors the temperature of the impeller 2, so that the precise control of the rigidity of blades is realized, and the impellers 2 in different wrap angles and placement angles are formed for the overcurrent media with different concentrations, so that the operation efficiency of the slurry pump under the overcurrent media with different concentrations is improved;
when the slurry concentration is lower, the stress of the blades is smaller under the same rotating speed and flow, the impeller 2 has smaller wrap angle and larger outlet setting angle, when the slurry concentration is higher, the stress of the blades is larger, the impeller 2 has larger wrap angle and smaller outlet setting angle, the performance range of the slurry pump is widened through the change of the shape of the blades, the slurry pump can be better adapted to conveying slurry media with different concentrations, and the working efficiency of the pump is improved.
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.
Claims (7)
1. A closed impeller slurry pump having controllable flexible blades, comprising:
the pump body (1) is internally provided with a pump shaft (3), the front end of the pump shaft (3) is provided with a front cover plate (4), and the rear end of the pump shaft (3) is provided with a rear cover plate (5);
the impeller (2) is an integrally cast metal piece, is arranged on the pump shaft (3) through a hub (24) and limited through a shaft end nut (31), the impeller (2) is matched with the front cover plate (4) and the rear cover plate (5) to form an overcurrent medium flow passage, a plurality of blades are uniformly distributed on the impeller (2), and the blades comprise cast iron (21), memory alloy strips (22) and flexible blades (23);
and the heating device is used for heating the pump shaft (3), transmitting heat to the memory alloy strip (22) through the pump shaft (3), and performing feedback adjustment according to the temperature of the memory alloy strip (22) so as to control the rigidity of the blade.
2. A closed impeller slurry pump with controllable flexible blades according to claim 1, characterized in that the heating means comprises an infrared heat sensing probe (71), a solenoid (72) and a controller (73), the solenoid (72) being wound on the pump shaft (3), the infrared heat sensing probe (71) and the controller (73) being mounted on the back cover plate (5).
3. A closed impeller slurry pump with controllable flexible blades according to claim 2, characterized in that the infrared heat sensing probe (71) is used to detect the impeller (2) temperature and to transmit a temperature signal to the controller (73) for adjusting the heating temperature of the electromagnetic coil (72).
4. A closed impeller slurry pump with controllable flexible blades according to claim 1, characterized in that the flexible blades (23) are internally wrapped with a number of memory alloy strips (22), the cast iron (21) and the flexible blades (23) being bonded by an adhesive.
5. A closed impeller slurry pump with controllable flexible blades according to claim 1, characterized in that the impeller (2) has a plurality of balancing holes (25).
6. The closed impeller slurry pump with the controllable flexible blades according to claim 1, wherein a plurality of round holes are circumferentially distributed on the front cover plate (4), second magnets (41) are placed in the round holes, and first magnets (11) forming magnetic attraction with the second magnets (41) are arranged at corresponding positions on the pump body (1).
7. A closed impeller slurry pump with controllable flexible blades according to claim 1, characterized in that the cooperation of the impeller (2) and the back cover plate (5) is provided with a labyrinth seal groove (52), and the cooperation of the back cover plate (5) with the pump body (1) and the pump shaft (3) is provided with a mechanical seal (6) and is positioned by a sealing cover (51).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN202310261346.6A CN116221128A (en) | 2023-03-17 | 2023-03-17 | Closed impeller slurry pump with controllable flexible blades |
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CN202310261346.6A CN116221128A (en) | 2023-03-17 | 2023-03-17 | Closed impeller slurry pump with controllable flexible blades |
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CN116221128A true CN116221128A (en) | 2023-06-06 |
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CN202310261346.6A Pending CN116221128A (en) | 2023-03-17 | 2023-03-17 | Closed impeller slurry pump with controllable flexible blades |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116892519A (en) * | 2023-09-07 | 2023-10-17 | 江苏新世界泵业有限公司 | Fluorine material axial flow pump with flexibly assembled components |
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2023
- 2023-03-17 CN CN202310261346.6A patent/CN116221128A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116892519A (en) * | 2023-09-07 | 2023-10-17 | 江苏新世界泵业有限公司 | Fluorine material axial flow pump with flexibly assembled components |
CN116892519B (en) * | 2023-09-07 | 2023-12-19 | 江苏新世界泵业有限公司 | Fluorine material axial flow pump with flexibly assembled components |
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