An adjustable anti-abrasion impeller of double-suction centrifugal pump

Abstract

The present invention belongs to the technical field of water conservancy engineering, and relates to an adjustable anti-wear impeller of a double-suction centrifugal pump; the impeller comprises a left impeller, a right impeller, an adjusting device and a fixed shaft device; a clamping connection is formed between the left cover plate and the right cover plate, and the left main shaft and the right main shaft rotate synchronously; the adjusting device comprises a left circular ring, a right circular ring and a telescopic device, the left circular ring is arranged on the inner side of the left cover plate, and the side wall of the left circular ring is evenly provided with left control holes along its circumferential direction; the right circular ring is arranged on the inner side of the right cover plate, and the side wall of the right circular ring is evenly provided with right control holes along its circumferential direction; the left control hole and the right control hole are arranged in a one-to-one correspondence; the telescopic device telescopes in the left control hole and the right control hole, the left impeller and the right impeller are relatively fixed or relatively rotated, and the left blades and the right blades are staggered; the present invention can adjust the staggered angle of the left and right impellers according to the sediment content, reduce the impeller wear, and improve the impeller abrasion characteristics.

Description

Technical Field

[0001] The invention belongs to the technical field of water conservancy engineering, and in particular relates to an adjustable anti-abrasion impeller of a double-suction centrifugal pump. Background Art

[0002] In the areas along the Yellow River in China, the pumping stations have large flow and high head, and most of them use double-suction centrifugal pumps. Nowadays, double-suction centrifugal pumps are widely used in pumping stations along the Yellow River. Due to the high sediment content in the middle reaches of the Yellow River, sand and other particles will be mixed into the water pumped by these pumps. These particles will impact the pump body and rotor components, which will cause wear of the pump body. At the same time, these particles will affect the flow field in the pump, thereby affecting the overall efficiency, head and service life of the pump. And because the impeller is a high-speed rotating component, its wear problem is more serious and has a more significant impact on performance. Different sediment particle sizes, sediment particle densities and sediment particle shapes will affect the wear characteristics of the flow components of the centrifugal pump. Therefore, at this stage, reducing the wear of the impeller in different concentrations of sandy water or in different sand contents is an important task to be dealt with by my country's water conservancy industry. Therefore, it is of great significance to improve the abrasive characteristics of the impeller of a double-suction centrifugal pump in different sand contents. Summary of the invention

[0003] The purpose of the present invention is to solve the deficiencies in the prior art and to provide an adjustable anti-abrasion impeller for a double-suction centrifugal pump.

[0004] In order to achieve the above-mentioned purpose, the present invention is realized through the following technical scheme: an adjustable anti-wear impeller of a double-suction centrifugal pump, comprising a left impeller, a right impeller, an adjusting device and a fixing shaft; the left impeller comprises a left cover plate, a left blade and a left main shaft, the outer surface of the left cover plate is provided with a left blade, and the left blade is evenly distributed along the circumferential direction of the left cover plate, the left main shaft is penetrated through the center of the left cover plate, and the fixing shaft is arranged at one end of the outer side of the left main shaft for adjusting the rotation of the left main shaft; the right impeller comprises a right cover plate, a right blade and a right main shaft, the outer surface of the right cover plate is provided with a right blade, and the right blade is evenly distributed along the circumferential direction of the right cover plate, the right main shaft is penetrated through the center of the right cover plate, and one end of the outer side of the right main shaft is connected to a motor; a clamping connection is formed between the left cover plate and the right cover plate, and the left main shaft rotates synchronously with the right main shaft;

[0005] The adjustment device includes a left circular ring, a right circular ring and a telescopic device. The left circular ring is arranged on the inner side of the left cover plate, and the side wall of the left circular ring is evenly provided with left control holes along its circumferential direction; the right circular ring is arranged on the inner side of the right cover plate, and the side wall of the right circular ring is evenly provided with right control holes along its circumferential direction; the left control holes and the right control holes are arranged one by one; the telescopic device telescopes in the left control holes and the right control holes, the left impeller and the right impeller are relatively fixed or relatively rotated, and the staggered angle of the left blade and the right blade can be adjusted. The staggered angle of the left and right impellers can be adjusted according to the sediment content to reduce the wear of the impeller and improve the abrasive characteristics of the impeller.

[0006] Furthermore, the staggered angle between the left impeller and the right impeller is adjusted according to the sediment concentration, and the adjustment angle satisfies:

[0007]

[0008] Among them, θ is the staggered angle between the left impeller and the right impeller; c is the actual sediment concentration; c′ is the maximum sediment concentration of the river; θ′ is the optimal staggered angle corresponding to the maximum sediment concentration in the simulation experiment; μ is the deviation value, ranging from 1.05 to 1.2.

[0009] Furthermore, six telescopic devices are provided, and the six telescopic devices are evenly distributed along the inner circumferential direction of the left cover plate.

[0010] Furthermore, the telescopic device is a hydraulic thruster.

[0011] Furthermore, the hydraulic thruster is provided with a wireless receiver, and the hydraulic thruster is electrically connected to the wireless receiver.

[0012] Furthermore, a probe is provided at one end of the hydraulic thruster, and the probe monitors the state of the hydraulic thruster.

[0013] Furthermore, a positioning hole is provided at one end of the outer side of the left main shaft; the axis fixing device is an electric push rod machine and a wireless receiver, and the electric push rod machine realizes upward or downward telescopic movement according to the signal of the wireless receiver.

[0014] Furthermore, a fixed axis rod is provided at the top end of the electric push rod machine; the fixed axis rod includes a fixed axis device A, a fixed axis device B and a spring, and the fixed axis device A and the fixed axis device B are connected by the spring.

[0015] Furthermore, the diameter of the left circular ring is smaller than the diameter of the right circular ring, and the telescopic mechanism passes through the left circular ring and the right circular ring in sequence.

[0016] Furthermore, the motor is a stepper motor, and the angular displacement of the relative rotation between the left ring and the right ring is controlled to be 10° by controlling the number of pulses of the stepper motor.

[0017] When the sediment concentration or the amount of sediment at the inlet changes, the wear characteristics of the flow components of the centrifugal pump caused by the sand-containing water flow change. The fixed double-suction centrifugal pump cannot adapt to all the flow states of sand-containing water flow, resulting in the deepening of the overall wear of the centrifugal pump impeller, especially the wear of the outlet of the blade working surface, which ultimately affects the overall efficiency, head and service life of the pump, causing a large amount of economic losses. When the present invention is in operation, the left and right cover plates will adjust the impeller staggered angle according to the sediment concentration or the amount of sediment at the inlet to reduce the degree of wear at the outlet of the blade working surface. As the sediment concentration increases, the impeller staggered angle will also increase to improve the impeller's anti-abrasion performance. When the sediment concentration at the inlet changes, the wireless receiver of the hydraulic thruster will receive a signal and retract the thrust rod. At this time, the fixed axis will fix the centrifugal pump impeller on one side, and the motor at the right main shaft will rotate. The rotation amplitude is 10° each time, and different rotation angles are adjusted according to different sediment concentrations. After turning the corresponding angle, the underwater probe can be used to observe whether the thrust rod is aligned with the corresponding hole. After receiving the corresponding signal, the hydraulic thruster will push the thrust rod out, fix the left and right rings to fix the impeller main shafts on both sides, and realize the synchronous rotation of the staggered impellers. Ultimately, the anti-abrasion characteristics of the staggered impellers in the corresponding sand-containing water flow are improved to ensure the efficient operation of the unit.

[0018] The invention has the following beneficial effects: it is suitable for pumping stations in areas along the Yellow River with high sand content, and solves the problem of impeller wear in sandy water with different concentrations. It can adapt to pump station projects with sandy water with different concentrations, significantly improve the abrasion resistance of the centrifugal pump impeller, improve the operating stability of the unit, and has a simple structure, reliable technology, low operating costs, and can also extend the service life of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of an adjustable anti-abrasion impeller of a double-suction centrifugal pump;

[0020] Figure 2 It is the structural schematic diagram of the left impeller;

[0021] Figure 3 It is the structural schematic diagram of the right impeller;

[0022] Figure 4 It is a structural schematic diagram of an axis fixing device;

[0023] Figure 5 It is a structural schematic diagram of another type of axis fixing device;

[0024] Figure 6 This is the wear distribution diagram of the double-suction centrifugal pump before the left and right impeller angles are adjusted;

[0025] Figure 7 This is the wear distribution diagram of the double-suction centrifugal pump after the left and right impeller angles are adjusted.

[0026] In the figure: 1. left impeller; 2. right impeller; 3. left cover plate; 4. left blade; 5. left main shaft; 6. right cover plate; 7. right blade; 8. right main shaft; 9. left ring; 10. left control hole; 11. right ring; 12. right control hole; 13. hydraulic thruster; 14. wireless receiver; 15. probe; 16. electric push rod machine; 17. fixed shaft rod; 18. spring; 19. fixing plate. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the embodiments, but they are not intended to limit the present invention.

[0028] like Figure 1-5 As shown, an adjustable anti-abrasion impeller of a double-suction centrifugal pump mainly includes a left impeller 1, a right impeller 2, an adjusting device and a shaft fixing device;

[0029] The left impeller 1 comprises a left cover plate 3, a left blade 4 and a left main shaft 5. The outer surface of the left cover plate 3 is provided with 7 left blades 4, and the 7 left blades 4 are evenly distributed along the circumference direction of the left cover plate 3. The left blades 4 are made of stainless steel. The left main shaft 5 is passed through the center of the left cover plate 3.

[0030] The right impeller 2 includes a right cover plate 6, a right blade 7 and a right main shaft 8. The outer surface of the right cover plate 6 is provided with 7 right blades 7, which are evenly distributed along the circumferential direction of the right cover plate 6, and the right blades 7 are made of stainless steel; the right main shaft 8 is passed through the center of the right cover plate 6; one end of the outer side of the right main shaft 8 is connected to a stepper motor; the stepper motor can be of NEMA17 (42mm×42mm) or NEMA23 (57mm×57mm), and any stepper motor that can control the rotation angle of the main shaft is within the protection scope of the present invention. The stepper motor is a prior art, and those skilled in the art can make a conventional selection according to their needs, which will not be described in detail here;

[0031] The left cover plate 3 and the right cover plate 6 are connected by staggered slots, and sealing measures are taken between the slots. One end of the left spindle 5 is attached to one end of the right spindle 8, and the left spindle 5 and the right spindle 8 rotate synchronously.

[0032] The axis fixer is arranged at the outer end of the left main shaft 5, and a positioning hole is provided at the outer end of the left main shaft 5. The axis fixer includes an electric push rod machine 16 and a wireless receiver. The axis fixer is fixed to the ground through a fixing plate 19. The bottom of the electric push rod machine 16 is connected to the fixing plate 19, and the wireless receiver is electrically connected to the electric push rod machine 16. When the wireless receiver receives the signal, the electric push rod machine 16 is controlled to move downward or upward; when the electric push rod machine 16 moves upward, the left main shaft 5 rotates slowly under the control of the stepper motor, and when the top of the electric push rod machine 16 is aligned with the positioning hole, the electric push rod machine 16 enters the positioning hole, and the left main shaft 5 is fixed; the electric push rod machine 16 is a prior art, and those skilled in the art can make a conventional selection according to their needs. The internal structure of the electric push rod machine is not described in detail here. In this embodiment, the electric push rod machine can adopt a DTZ type electric push rod machine;

[0033] The adjusting device comprises a left circular ring 9, a right circular ring 11 and a telescopic device; the left circular ring 9 is arranged on the inner side of the left cover plate 3, and the side wall of the left circular ring 9 is evenly provided with 36 left control holes 10 along its circumferential direction; the right circular ring 11 is arranged on the inner side of the right cover plate 6, and the side wall of the right circular ring 11 is evenly provided with 36 right control holes 12 along its circumferential direction; the telescopic device is a hydraulic thruster 13, and 6 hydraulic thrusters 13 are arranged in the left circular ring 9. The hydraulic thrusters can adopt the hydraulic thrusters of the DYTP series or the DYTZ series, and each The hydraulic thrusters are equipped with corresponding wireless receivers 14 and probes 15. A runoff sediment measuring instrument (such as RSMI series runoff sediment measuring instrument) is provided at the water inlet. The runoff sediment measuring instrument is provided with a sensor, which is connected to the control platform to transmit the measurement data to the control platform, and then the control platform sends a corresponding signal. After the wireless receiver 14 in the adjustment device receives the signal, the hydraulic thruster 13 is controlled to be retracted from the control hole. The right impeller is controlled by the stepper motor to adjust the staggered angle of the left and right impellers by 10°.

[0034] Adjustment angle meets:

[0035]

[0036] Among them, θ is the staggered angle between the left impeller 1 and the right impeller 2; c is the actual sediment concentration; c′ is the maximum sediment concentration of the river; θ′ is the optimal staggered angle corresponding to the maximum sediment concentration in the simulation experiment; μ is the deviation value, ranging from 1.05 to 1.2.

[0037] like Figure 6 As shown, in another embodiment, a fixed axis rod 17 is provided on the top of the electric push rod machine, and the fixed axis rod 17 includes a fixed axis rod A, a fixed axis rod B and a spring 18. The fixed axis rod A and the fixed axis rod B are connected by the spring 18. When the fixed axis rod is not aligned with the positioning hole, the spring 18 is compressed to prevent the upward force of the fixed axis rod 17 from causing damage to the left spindle.

[0038] Principle: Make the double-suction centrifugal pump impeller according to relevant standards, install the hydraulic thruster 13 on the inner side of the left impeller 1, and the left impeller 1 and the right impeller 2 are sealed by staggered slots to form a double-suction centrifugal pump impeller. The left ring 9 is located inside the right ring 11, and the right control hole 12 of the right ring 11 corresponds to the left control hole 10 of the left ring 9 one by one. The outer side of the right main shaft 8 is connected to a stepper motor. The water inlet and the water outlet are vertically distributed with the main shaft, and a runoff sediment measuring instrument is provided at the water inlet.

[0039] When in use, the left blade 4 corresponds to the right blade 7 one by one, and the hydraulic thruster 13 extends through the left control hole 10 and the right control hole 12 in turn to ensure that the left impeller 1 and the right impeller 2 are relatively fixed, and the stepper motor is started to drive the right main shaft 8 to rotate and synchronously drive the left main shaft 5 to rotate; the runoff sediment measuring instrument at the water inlet transmits data to the control platform. When the sediment content is large, the control platform sends a signal to the wireless receiver in the fixed axis device to control the electric push rod machine 16 to drive the fixed axis rod 17 to move upward, and at the same time, the stepper motor drives the main shaft to rotate slowly. When the fixed axis rod 1 7 is most accurate with the positioning hole, the fixed axis rod 17 enters the positioning hole, and the left main shaft 5 stops rotating; the wireless receiver 14 on the hydraulic thruster 13 receives the signal, and the hydraulic thruster 13 is retracted from the right control hole 12 and the left control hole 10, and the angular displacement of the right ring 11 and the left ring 9 is controlled to be 10° by controlling the number of pulses of the stepper motor, and then the hydraulic thruster 13 extends out and passes through the left control hole 10 and the right control hole 12 in turn; the probe on the hydraulic thruster 13 detects whether the left and right control holes correspond one to one and whether the hydraulic thruster passes through the left and right control holes.

[0040] Simulation experiment: Figure 6 and Figure 7 As shown, compared with the existing double-suction centrifugal pump, the device is equipped with a probe 15 and a wireless receiver 14, which can be controlled in real time. Fixed double-suction centrifugal pumps cannot adapt to all sand-containing water flow states, which will increase the wear degree of the blade working surface outlet. However, the present invention can adjust the staggered angle of the left and right impellers according to the amount of sediment at the inlet to reduce the wear degree of the blade working surface outlet, significantly improve the abrasion resistance of the centrifugal pump impeller, ensure the efficient operation of the unit, extend the service life of the unit, improve the engineering benefits, and have broad application prospects.

[0041] The above shows and describes the basic principles, main features and advantages of the present invention. However, the above is only a specific embodiment of the present invention, and the technical features of the present invention are not limited thereto. Any other implementation methods derived by any technician in the field without departing from the technical solution of the present invention should be included in the patent scope of the present invention.

Claims

1. An adjustable double-suction centrifugal pump anti-abrasion impeller, characterized in that: The invention comprises a left impeller (1), a right impeller (2), an adjusting device and a shaft fixing device; the left impeller (1) comprises a left cover plate (3), a left blade (4) and a left main shaft (5); the left blade (4) is arranged on the outer surface of the left cover plate (3); the left blade (4) is evenly distributed along the circumferential direction of the left cover plate (3); the left main shaft (5) is passed through the center of the left cover plate (3); the shaft fixing device is arranged at one end of the outer side of the left main shaft (5) and is used to adjust the rotation of the left main shaft (5); The right impeller (2) comprises a right cover plate (6), a right blade (7) and a right main shaft (8); the outer surface of the right cover plate (6) is provided with a right blade (7), and the right blades (7) are evenly distributed along the circumferential direction of the right cover plate (6); the right main shaft (8) is passed through the center of the right cover plate (6), and one outer end of the right main shaft (8) is connected to the motor; the left cover plate (3) and the right cover plate (6) are clamped together, and the left main shaft (5) and the right main shaft (8) rotate synchronously; The regulating device comprises a left circular ring (9), a right circular ring (11) and a telescopic device. The left circular ring (9) is arranged on the inner side of the left cover plate (3). The side wall of the left circular ring (9) is evenly provided with left control holes (10) along its circumferential direction. The right circular ring (11) is arranged on the inner side of the right cover plate (6). The side wall of the right circular ring (11) is evenly provided with right control holes (12) along its circumferential direction. The left control holes (10) and the right control holes (12) are arranged in a one-to-one correspondence. The telescopic device telescopes in the left control hole (10) and the right control hole (12). The left impeller (1) and the right impeller (2) are relatively fixed or relatively rotated. The staggered angle of the left blade (4) and the right blade (7) can be adjusted. The diameter of the left circular ring (9) is smaller than the diameter of the right circular ring (11). The telescopic mechanism passes through the left circular ring (9) and the right circular ring (11) in sequence. The staggered angle between the left impeller (1) and the right impeller (2) is adjusted according to the sediment concentration, and the adjustment angle satisfies: Wherein, θ is the staggered angle between the left impeller (1) and the right impeller (2); c is the actual sediment concentration; c′ is the maximum sediment concentration of the river; θ′ is the optimal staggered angle corresponding to the maximum sediment concentration in the simulation experiment; μ is the deviation value, ranging from 1.05 to 1.

2.

2. The adjustable double-suction centrifugal pump anti-abrasion impeller according to claim 1 is characterized in that: The telescopic devices are provided in six numbers, and the six telescopic devices are evenly distributed along the inner circumferential direction of the left cover plate (3).

3. The adjustable double-suction centrifugal pump anti-abrasion impeller according to claim 1 is characterized in that: The telescopic device is a hydraulic thruster (13).

4. The adjustable double-suction centrifugal pump anti-abrasion impeller according to claim 3 is characterized in that: The hydraulic thruster (13) is provided with a wireless receiver (14), and the hydraulic thruster (13) is electrically connected to the wireless receiver (14).

5. The adjustable double-suction centrifugal pump anti-abrasion impeller according to claim 3, characterized in that: A probe (15) is provided at one end of the hydraulic thruster (13), and the probe (15) monitors the state of the hydraulic thruster (13).

6. The adjustable anti-abrasion impeller of double-suction centrifugal pump according to claim 1, characterized in that: A positioning hole is provided at one outer end of the left main shaft (5); the axis fixing device is an electric push rod machine (16) and a wireless receiver, and the electric push rod machine (16) realizes upward or downward telescopic movement according to the signal of the wireless receiver.

7. The adjustable anti-abrasion impeller of double-suction centrifugal pump according to claim 6, characterized in that: A fixed axis rod (17) is provided at the top end of the electric push rod machine (16); the fixed axis rod (17) comprises a fixed axis device A, a fixed axis device B and a spring (18), and the fixed axis device A and the fixed axis device B are connected via the spring (18).

8. The adjustable anti-abrasion impeller of double-suction centrifugal pump according to claim 1, characterized in that: The motor is a stepping motor, and the angular displacement of the relative rotation of the left ring (9) and the right ring (11) is controlled to be 10° by controlling the number of pulses of the stepping motor.

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