Driving system of chemical volume charging pump

Abstract

The invention provides a chemical volume charging pump driving system which comprises a driving motor and a water turbine, the driving motor is provided with a driving shaft, and one end of the driving shaft is connected with a chemical volume charging pump; the water turbine is provided with a rotating shaft and a water bucket mounted on the rotating shaft; the rotating shaft is coaxially connected with the other end of the driving shaft; wherein the water turbine is provided with a nozzle, the nozzle is connected with a small-flow circulating pipeline of the chemical volume charging pump, and the nozzle is used for spraying the received high-energy liquid to the water bucket to drive the rotating shaft to rotate, so that the output of the driving motor is reduced. According to the chemical-volume charging pump driving system, the water turbine is arranged on one side of the driving motor, and the water turbine and the chemical-volume charging pump rotate in the same direction, so that a small-flow circulating high-energy medium originally wasted by the chemical-volume charging pump does work on the water turbine, shaft power output by the water turbine is fed back to the chemical-volume charging pump, and the shaft power consumed by the driving motor is reduced; the efficiency of the pump unit is improved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical volume charging pump drive design, and in particular to a chemical volume charging pump drive system. Background Art

[0002] In an integrated small reactor, the chemical volume charging pump is an important equipment in the RCS system (chemical and volume control system), which is used to realize the functional requirements of filling the reactor coolant system with water, maintaining the coolant water chemistry and the water loading amount of the reactor coolant system.

[0003] The chemical volume charging pump adopts the structure of a horizontal multi-stage centrifugal pump, with a design flow rate of 10m3 / h and a design head of 1289m~1459m. There is currently no mature pump type available for horizontal multi-stage centrifugal pumps with such performance parameters, and the development is difficult. According to the survey, the pump efficiency given by the pump manufacturer is about 30%, and the matching motor power is more than 315kW. Since the integrated small reactor relies on external power supply, the equipment power consumption is required to be as low as possible, and the chemical volume charging pump has a very low specific speed of the hydraulic model, so it is very difficult to improve the hydraulic efficiency.

[0004] Based on this, the inventor of the present application proposes a chemical volume charging pump driving system in order to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defect of low efficiency of chemical volume charging pump units in the prior art and to provide a chemical volume charging pump driving system.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] The present invention provides a chemical volume charging pump driving system, which is characterized in that it includes:

[0008] A driving motor having a driving shaft, one end of which is connected to a chemical volume charging pump;

[0009] The water turbine comprises a rotating shaft and a water bucket mounted on the rotating shaft, wherein the rotating shaft is coaxially connected to the other end of the driving shaft; wherein:

[0010] The water turbine is provided with a nozzle, which is connected to a small flow circulation pipeline of a chemical volume charging pump. The nozzle is used to spray the received high-energy liquid to the water bucket to drive the rotating shaft to rotate, thereby reducing the output of the driving motor.

[0011] According to one embodiment of the present invention, the water turbine includes a casing and a cover, the casing and the cover enclose an installation space, one end of the rotating shaft passes through the installation space and extends outside the installation space and is connected to the driving shaft through a coupling.

[0012] According to one embodiment of the present invention, one end of the nozzle is disposed through the machine cover and extends into the installation space;

[0013] The nozzle is provided with a regulating valve, and the regulating valve is used to adjust the flow rate of the nozzle.

[0014] According to one embodiment of the present invention, there are multiple water buckets, and the multiple water buckets are evenly spaced around the circumference of the rotating shaft.

[0015] According to one embodiment of the present invention, the rotating shaft includes an axis body and a runner hub axially arranged around the axis body, and the water bucket is installed on the runner hub.

[0016] According to one embodiment of the present invention, the wheel hub is provided with a plurality of matching holes along its circumference, and one end of the water bucket is inserted into the matching holes and matched with the thread of the wheel hub;

[0017] The wheel hub is also provided through the water bucket and the matching hole via a latch pin to limit the water bucket.

[0018] According to an embodiment of the present invention, a support bearing is respectively provided at both ends of the rotating shaft, and a mechanical seal is provided between the support bearing and the rotating shaft;

[0019] The machine cover is provided with a mechanical seal flushing pipe, one end of which extends into the installation space and faces the mechanical seal.

[0020] According to an embodiment of the present invention, a water return pipe is further provided at the bottom of the casing, and the water return pipe is used to discharge water in the installation space.

[0021] According to one embodiment of the present invention, a base is further included, and the driving motor and the water turbine are detachably mounted on the base.

[0022] According to one embodiment of the present invention, the driving motor, the water turbine and the chemical volume charging pump are coaxial and rotate in the same direction.

[0023] The positive and progressive effects of the present invention are:

[0024] The chemical capacity charging pump driving system of the present invention is provided with a water turbine on one side of the driving motor, and the water turbine and the chemical capacity charging pump are made to rotate in the same direction. Therefore, the small flow rate circulating high-energy medium originally wasted by the chemical capacity charging pump is used to do work for the water turbine, and the shaft power output by the water turbine is fed back to the chemical capacity charging pump, so as to reduce the shaft power consumed by the driving motor and improve the efficiency of the pump unit.

[0025] That is, the torque generated by the rotation of the turbine can be transmitted to the chemical capacity charging pump, which offsets part of the torque of the chemical capacity charging pump, thereby reducing the torque output of the drive motor, thereby reducing the motor power and ultimately improving the efficiency of the chemical capacity charging pump unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0027] Figure 1 It is a schematic diagram of the connection between the chemical volume charging pump driving system and the chemical volume charging pump of the present invention;

[0028] Figure 2 for Figure 1 A schematic diagram of the interior of a turbine;

[0029] Figure 3 for Figure 1 A cross-sectional view of a water turbine at one angle.

[0030] 1. Driving motor; 11. Driving shaft;

[0031] 2. Chemical volume charging pump;

[0032] 3. Turbine; 31. Rotating shaft; 311. Shaft body; 312. Wheel hub; 313. Matching hole; 314. Latch; 315. Support bearing; 316. Mechanical seal; 32. Water bucket; 33. Nozzle; 331. Regulating valve; 34. Casing; 341. Mechanical seal flushing pipe; 342. Return pipe; 35. Machine cover; 36. Installation space; 37. Coupling;

[0033] 4. Base. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0036] Please refer to Figures 1 to 3 The present invention proposes a chemical volume charging pump driving system, the system includes a driving motor 1 and a turbine 3, the driving motor 1 has a driving shaft 11, one end of the driving shaft 11 is connected to the chemical volume charging pump 2; the turbine 3 has a rotating shaft 31 and a water bucket 32 ​​installed on the rotating shaft 31, the rotating shaft 31 is coaxially connected to the other end of the driving shaft 11; wherein, a nozzle 33 is provided on the turbine 3, the nozzle 33 is connected to the small flow circulation pipeline of the chemical volume charging pump 2, and the nozzle 33 is used to spray the received high-energy liquid to the water bucket 32 ​​to drive the rotating shaft 31 to rotate, thereby reducing the output of the driving motor 1.

[0037] The present invention selects the Pelton turbine because the operating efficiency of the Pelton turbine is high and the efficiency varies slightly with the flow rate.

[0038] It can be seen that the chemical volume charging pump 2 is a small flow, high head multistage centrifugal pump. The operating point of the pump is in the low efficiency area of ​​the performance curve. Most of the work of the hydraulic components is used to generate heat. As the pump runs, the temperature of the medium in the pump continues to rise, which is not conducive to the safe operation of the pump unit.

[0039] In order to reduce the temperature of the medium in the pump and improve the operating reliability of the pump unit, it is necessary to increase the operating flow of the pump so that the pump operates in a higher efficiency area, and then release the unnecessary flow in a small flow cycle. Although this improves the operating reliability of the pump unit, it also causes energy waste.

[0040] Among them, since the medium of the small flow circulation is a high-energy liquid with a small flow and high head, the device for converting the potential energy of the high-energy liquid into mechanical energy is the turbine 3. Based on this, the present invention connects the rotor of the turbine 3 with the rotor of the pump unit to form a coaxial turbine 3 device, converts the mechanical energy of the turbine 3 into useful work, offsets the shaft power consumed by the pump, and will achieve the purpose of improving the efficiency of the pump unit.

[0041] That is, the present invention effectively utilizes the high-energy medium in the small-flow circulation pipeline wasted by the chemical volume charging pump 2, and drives the turbine 3 to do work. At the same time, through the coaxial design of the turbine 3 and the drive motor 1, the shaft power output by the turbine 3 is fed back to the drive motor 1 and the chemical volume charging pump 2, thereby reducing the shaft power consumed by the pump unit and improving the efficiency of the pump unit.

[0042] Specifically, the turbine 3 includes a casing 34 and a cover 35 , which enclose an installation space 36 , and one end of the rotating shaft 31 passes through the installation space 36 and extends outside the installation space 36 and is connected to the driving shaft 11 through a coupling 37 .

[0043] It can be known that the housing 34 and the cover 35 can be detachably connected through a plurality of threaded connectors, and the water bucket 32 ​​in the installation space 36 is used to receive the high-energy medium of the chemical volume charging pump 2 and drive the rotating shaft 31 to rotate.

[0044] Please refer to Figure 2 One end of the nozzle 33 is passed through the machine cover 35 and extends into the installation space 36 ; a regulating valve 331 is provided on the nozzle 33 , and the regulating valve 331 is used to adjust the flow rate of the nozzle 33 .

[0045] By arranging a regulating valve 331 at the front end of the nozzle 33 , the flow rate and pressure of the nozzle 33 can be adjusted as needed, and the shaft power output by the turbine 3 can be adjusted.

[0046] It should be noted that there are multiple water buckets 32 , and the multiple water buckets 32 are evenly spaced around the circumference of the rotating shaft 31 .

[0047] The number of the water buckets 32 may be, for example, 6, 8, or 12. Twelve water buckets are taken as an example for description herein, but are not limited thereto.

[0048] Please continue to refer to Figure 2 and Figure 3 The rotating shaft 31 includes an axis body 311 and a runner hub 312 axially arranged around the axis body 311 , and the water bucket 32 ​​is installed on the runner hub 312 .

[0049] Specifically, the wheel hub 312 is provided with a plurality of mating holes 313 along its circumference, one end of the water bucket 32 ​​is inserted into the mating hole 313 and is threadedly mated with the wheel hub 312; the wheel hub 312 is also provided with a pin 314 which penetrates the water bucket 32 ​​and the mating hole 313 to limit the water bucket 32.

[0050] That is, the water bucket 32 ​​and the wheel hub 312 are detachably connected via threads. For example, during installation, all the water buckets 32 are first rotated and installed to the target position and adjusted to the target angle, and then the water buckets 32 are limited by the pins 314 to prevent the water buckets 32 from deflecting relative to the wheel hub 312 under the impact of high-energy media.

[0051] In this way, by means of the threaded fitting of the latch pin 314, the installation stability of the water bucket 32 ​​is ensured, and at the same time, the water bucket 32 ​​and the impeller hub 312 are easily disassembled, which is convenient for inspection and replacement.

[0052] In one embodiment, a support bearing 315 is provided at each end of the rotating shaft 31 , and a mechanical seal 316 is provided between the support bearing 315 and the rotating shaft 31 ; a mechanical seal flushing pipe 341 is provided on the machine cover 35 , and one end of the mechanical seal flushing pipe 341 extends into the installation space 36 and faces the mechanical seal 316 .

[0053] It can be seen that the small flow circulation pipeline of the chemical volume charging pump 2 can be connected to the nozzle 33 and the mechanical seal flushing pipe 341 can be connected at the same time to flush the mechanical seal 316 with the medium connected to the pump end. At the same time, a return pipe 342 is also provided at the bottom of the casing 34, and one end of the return pipe 342 is connected to the system drain pipeline to discharge the medium to the outside of the turbine 3.

[0054] In one embodiment, a base 4 is further included, and the driving motor 1 and the water turbine 3 are detachably mounted on the base 4 .

[0055] During assembly, the chemical volume charging pump 2, the drive motor 1 and the turbine 3 are installed on the base 4 in sequence, and the coupling 37 is angularly and radially aligned. Then, the small flow circulation pipeline of the chemical volume charging pump 2 is connected to the nozzle 33 of the turbine 3, and the mechanical seal flushing pipe 341 is connected, and the return pipe 342 is connected to the drain pipeline.

[0056] When the system is started, after the chemical volume charging pump 2 is started, the rotating shaft 31 of the turbine 3 and the unit rotor of the chemical volume charging pump 2 run together. After the pump establishes flow and head, the high-energy liquid in the small flow circulation pipeline is sprayed to the bucket 32 ​​through the nozzle 33, so that the rotating shaft 31 of the turbine 3 generates torque and outputs shaft power to the unit of the chemical volume charging pump 2. This shaft power will offset part of the shaft power of the chemical volume charging pump 2, reduce the output of the drive motor 1, and improve the unit efficiency of the chemical volume charging pump 2. The medium after the work of the bucket 32 ​​of the turbine 3 is discharged from the return pipe 342. The regulating valve 331 set at the front end of the nozzle 33 can adjust the flow and pressure of the jet according to actual needs, thereby adjusting the shaft power output of the turbine 3.

[0057] The main parameters of turbine 3 are as follows:

[0058] Among them, the diameter of the runner of turbine 3 is calculated as:

[0059] To ensure the optimal unit speed of turbine 3, set:

[0060] Speed ​​ratio 0 =0.48, nozzle 33 efficiency

[0061] The speed of turbine 3 is the same as the pump speed, n = 2980 rpm.

[0062] The working water head of turbine 3 is the same as the head of the small flow circulation pipeline of chemical volume charging pump 2, H=1200m.

[0063] According to the formula Where g is the acceleration due to gravity.

[0064] Calculate the runner diameter D of turbine 3 1 =0.465m.

[0065] Then, the output of turbine 3 is calculated as:

[0066] N = 9.81HQη;

[0067] The flow rate Q of turbine 3 is the same as the flow rate of small flow rate circulation of chemical volume charging pump 2, Q = 11m 3 / h.

[0068] The working water head of turbine 3 is H=1200m.

[0069] The initial efficiency of turbine 3 is η=0.9.

[0070] Then the output of turbine 3 is N=32.373kW.

[0071] The nozzle 33 jet diameter is also calculated as:

[0072] According to the formula

[0073] Calculate the nozzle 33 jet diameter d 0 =0.005m.

[0074] That is, the flow rate, head and pump speed of the small flow circulation pipeline of the chemical volume charging pump 2 are used as the input parameters of the turbine 3, and the main technical parameters of the turbine 3 such as the turbine 3 runner diameter, turbine 3 output, nozzle 33 jet diameter are calculated, which can provide a reference for the turbine design.

[0075] In summary, the chemical volume charging pump driving system provided by the present invention effectively utilizes the small-flow circulating high-energy medium originally wasted by the chemical volume charging pump 2 to do work for the turbine 3. Through the coaxial design of the turbine 3 and the pump unit, the shaft power output by the turbine 3 is fed back to the pump unit to reduce the shaft power consumed by the pump unit. Since the torque is proportional to the power, the power of the driving motor 1 decreases, and the efficiency of the pump unit will increase, thereby improving the efficiency of the pump unit.

[0076] Moreover, the water turbine 3 and the volumetric charging pump 2, two mechanical devices with completely opposite functions, are combined together, and the advantages of the water turbine 3 are used to compensate for the disadvantages of the small-flow multi-stage centrifugal pump, thereby achieving the effect of energy saving and emission reduction.

[0077] Finally, the bucket 32 ​​of the water turbine 3 and the runner hub 312 are fastened by a combination of threads and latches 314, which ensures the reliability of installation and the convenience of disassembly and assembly of the bucket 32 ​​and the runner hub 312.

[0078] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "install", "connect", "connect", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can also be a mechanical connection. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0079] The present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0080] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A chemical volume charging pump driving system, characterized in that: include: A driving motor having a driving shaft, one end of which is connected to a chemical volume charging pump; The water turbine comprises a rotating shaft and a water bucket mounted on the rotating shaft, wherein the rotating shaft is coaxially connected to the other end of the driving shaft; wherein: The water turbine is provided with a nozzle, which is connected to a small flow circulation pipeline of a chemical volume charging pump. The nozzle is used to spray the received high-energy liquid to the water bucket to drive the rotating shaft to rotate, thereby reducing the output of the driving motor.

2. The chemical volume charging pump driving system according to claim 1, characterized in that: The water turbine comprises a casing and a cover, wherein the casing and the cover enclose an installation space, and one end of the rotating shaft passes through the installation space and extends outside the installation space and is connected to the driving shaft through a coupling.

3. The chemical volume charging pump driving system according to claim 2, characterized in that: One end of the nozzle is disposed through the machine cover and extends into the installation space; The nozzle is provided with a regulating valve, and the regulating valve is used to adjust the flow rate of the nozzle.

4. The chemical volume charging pump driving system according to claim 2, characterized in that: There are multiple water buckets, and the multiple water buckets are evenly spaced around the circumference of the rotating shaft.

5. The chemical volume charging pump driving system according to claim 4, characterized in that: The rotating shaft comprises an axis body and a runner hub axially arranged around the axis body, and the water bucket is installed on the runner hub.

6. The chemical volume charging pump driving system according to claim 5, characterized in that: The wheel hub is provided with a plurality of matching holes along its circumference, and one end of the water bucket is inserted into the matching hole and matched with the thread of the wheel hub; The wheel hub is also provided through the water bucket and the matching hole via a latch pin to limit the water bucket.

7. The chemical volume charging pump driving system according to claim 2, characterized in that: A support bearing is respectively arranged at both ends of the rotating shaft, and a mechanical seal is arranged between the support bearing and the rotating shaft; A mechanical seal flushing pipe is provided on the machine cover, and one end of the mechanical seal flushing pipe extends into the installation space and faces the mechanical seal.

8. The chemical volume charging pump driving system according to claim 2, characterized in that: A water return pipe is also provided at the bottom of the casing, and the water return pipe is used to discharge water in the installation space.

9. The chemical volume charging pump driving system according to claim 1, characterized in that: It also includes a base, and the driving motor and the water turbine are detachably mounted on the base.

10. The chemical volume charging pump driving system according to claim 1, characterized in that: The driving motor, the water turbine and the chemical volume charging pump rotate coaxially and in the same direction.

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