Nuclear reactor shield pump

Abstract

The invention relates to a nuclear reactor shield pump, and the nuclear reactor shield pump comprises a cavity assembly which forms a motion cavity; one end of the driving shaft is used for being connected with a rotor of the nuclear reactor shield pump, the other end of the driving shaft extends into the movement cavity, and a main shaft exhaust hole is formed in the driving shaft; the impeller is arranged in the movement cavity and connected with the driving shaft, the impeller is provided with a plurality of fan blades arranged in the circumferential direction of the driving shaft, the surface of at least one fan blade is provided with blade exhaust holes, and the blade exhaust holes communicate with the main shaft exhaust holes. Therefore, timely discharge and treatment of nitrogen can be realized through the fan blade exhaust hole, the main shaft exhaust hole and the exhaust pipe, the stability of depressurization operation of the nuclear reactor shield pump is improved to a great extent, and safe operation of the nuclear reactor shield pump can be ensured.

Description

Technical Field

[0001] The present application relates to the technical field of nuclear reactor shielding pumps, and in particular to a nuclear reactor shielding pump. Background Art

[0002] Nuclear reactor canned motor pumps are critical equipment in nuclear reactors. Their primary function is to ensure the circulation of coolant within the reactor system. Their unique shielding design effectively prevents the leakage of radioactive materials into the environment, thereby ensuring the safe operation of nuclear power plants. They utilize electromagnetic induction to directly convert electrical energy into mechanical energy, driving the pump's impeller for efficient fluid transport. The core advantage of these pumps is that they eliminate the need for mechanical seals. Their non-contact design, comprised of a shield sleeve and ring, effectively isolates the pumped medium from direct contact with the motor, preventing leakage and contamination.

[0003] During operation, when a nuclear reactor canned motor pump contains or releases a large amount of gas in the fluid, this gas is rapidly released in the low-pressure area, forming bubbles. These bubbles follow the flow of the fluid and quickly burst upon entering the high-pressure area, generating a strong shock wave that causes mechanical damage to the pump body and impeller surface. This phenomenon of gas-induced damage to the pump body and impeller surface is called cavitation. Summary of the Invention

[0004] Based on this, it is necessary to provide a nuclear reactor shield pump to address the problem of cavitation in the nuclear reactor shield pump.

[0005] A nuclear reactor shield pump, comprising an exhaust structure, wherein the exhaust structure comprises:

[0006] a cavity assembly, forming a motion chamber;

[0007] A drive shaft, one end of which is connected to the rotor of the nuclear reactor shield pump and the other end of which extends into the motion chamber, and a main shaft exhaust hole is provided on the drive shaft;

[0008] an impeller disposed in the motion chamber and connected to the drive shaft, the impeller having a plurality of blades circumferentially arranged around the drive shaft, at least one of the blades having a blade exhaust hole formed on its surface, the blade exhaust hole being in communication with the main shaft exhaust hole;

[0009] An exhaust pipe has one end extending out of the motion chamber and the other end communicating with the main shaft exhaust hole.

[0010] In one embodiment, the exhaust structure further includes a fastener, which is provided at one end of the drive shaft where the impeller is provided, and is used to fix the impeller to the drive shaft;

[0011] A central exhaust hole is provided on one end of the fastener away from the driving shaft, and the central exhaust hole is communicated with the main shaft exhaust hole.

[0012] In one embodiment, the blade exhaust hole is located on a surface of the impeller facing the fastener.

[0013] In one embodiment, the drive shaft is provided with a threaded hole on one end surface located in the motion chamber, and the threaded hole is communicated with the main shaft exhaust hole;

[0014] The fastener is a bolt, the bolt is threadedly connected to the threaded hole, and the central exhaust hole passes through the bolt along the axial direction of the threaded hole.

[0015] In one embodiment, the impeller is provided with a mounting hole and a keyway located on the inner wall of the mounting hole, the exhaust structure further includes a flat key provided on the drive shaft, and the extension direction of the flat key is parallel to the axis of the drive shaft, the drive shaft is passed through the mounting hole, and the flat key is provided in the keyway;

[0016] The drive shaft further includes a position-limiting step portion, the position-limiting step portion and the bolt are arranged at intervals along the axial direction of the drive shaft, and the impeller is arranged between the position-limiting step portion and the bolt.

[0017] In one embodiment, the blade exhaust hole on the fan blade passes through the inner wall of the mounting hole, and a connecting hole is opened on the circumferential side wall of the drive shaft, and the connecting holes are connected to the blade exhaust hole and the main shaft exhaust hole.

[0018] In one embodiment, the exhaust structure further includes a sleeve, the sleeve includes a sliding hole, the drive shaft is passed through the sliding hole, an air collecting cavity is formed inside the sleeve, and the exhaust pipe is connected to the air collecting cavity;

[0019] An annular hole is provided on the inner wall of the sliding hole, the annular hole is connected to the air collecting chamber, and is arranged circumferentially around the drive shaft. An air outlet hole is provided on the circumferential side wall of the drive shaft, the air outlet hole is connected to the annular hole, and when the drive shaft rotates around its own axis, the air outlet hole moves along the annular hole.

[0020] In one embodiment, a movable protrusion is provided on the driving shaft, the movable protrusion is passed through the annular hole, and part of the movable protrusion is located in the air collecting cavity, and the air outlet is located on the part of the movable protrusion located in the air collecting cavity.

[0021] In one embodiment, the motion chamber includes a flywheel sub-chamber and an impeller sub-chamber, the impeller is disposed in the impeller sub-chamber, the drive shaft passes through the flywheel sub-chamber and the impeller sub-chamber, and the shaft sleeve and the exhaust pipe are both disposed in the flywheel sub-chamber;

[0022] The exhaust structure further includes a flywheel, which is arranged on the drive shaft and located in the flywheel sub-cavity.

[0023] In one embodiment, the exhaust structure further includes an exhaust valve, which is provided in the cavity assembly and located outside the motion chamber, and the exhaust valve is connected to the exhaust pipe.

[0024] With the aforementioned exhaust structure, when the drive shaft drives the impeller to rotate, nitrogen precipitates at the impeller and enters the blade exhaust holes on the surface of the fan blades. The nitrogen then enters the main shaft exhaust hole through the blade exhaust holes. Centrifugal force generated by the drive shaft during rotation drives the nitrogen in the exhaust holes into the exhaust pipe, where it is discharged into the atmosphere. This allows for the timely discharge and treatment of nitrogen through the fan blade exhaust holes, the main shaft exhaust holes, and the exhaust pipe, significantly improving the stability of the depressurized operation of the nuclear reactor canned motor pump and ensuring its safe operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a nuclear reactor shielding pump in some embodiments of the present application.

[0026] Figure 2 for Figure 1 Enlarged view of point A in the middle.

[0027] Figure 3 for Figure 2 Enlarged view of point B in the middle.

[0028] Description of reference numerals:

[0029] Rotor 100; Stator 200;

[0030] Cavity assembly 10; motion chamber 11; flywheel chamber 12; impeller chamber 13;

[0031] Drive shaft 20; spindle exhaust hole 21; threaded hole 22; flat key 23; limit step 24; connecting hole 25; exhaust hole 26; movable protrusion 27;

[0032] Impeller 30; fan blade 31; blade exhaust hole 32; fastener 33; center exhaust hole 34; mounting hole 35; bolt 36;

[0033] Exhaust pipe 40; exhaust valve 41;

[0034] Sleeve 50; sliding hole 51; air collecting cavity 52; annular hole 53;

[0035] Flywheel 60. DETAILED DESCRIPTION

[0036] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0037] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0038] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0039] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0040] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0041] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0042] See Figure 1 、 Figure 2 and Figure 3 To address the cavitation problem of a nuclear reactor canned motor pump, one embodiment of the present application provides a nuclear reactor canned motor pump. The nuclear reactor canned motor pump includes an exhaust structure, which includes: a cavity assembly 10, a drive shaft 20, an impeller 30, and an exhaust pipe 40. A motion chamber 11 is formed within the cavity assembly 10. One end of the drive shaft 20 is used to connect to the rotor of the nuclear reactor canned motor pump, and the other end is located in the motion chamber 11. The impeller 30 is disposed in the motion chamber 11 and is connected to the end of the drive shaft 20 located in the motion chamber 11. The impeller 30 has a plurality of blades 31 arranged circumferentially around the drive shaft 20.

[0043] During actual use, the motion chamber 11 is filled with fluid material and is connected to external working parts. When the rotor in the nuclear reactor shield pump drives the drive shaft 20 to rotate, the drive shaft 20 drives the impeller 30 to rotate, and drives the fluid material to move through the blades 31 of the impeller 30, thereby pumping the fluid material into the external working parts to complete the transportation of the liquid.

[0044] Alternatively, the fluid material transported by the nuclear reactor shield pump can be a coolant. When the nuclear reactor shield pump is used in a nuclear reactor system, it is necessary to cooperate with a nitrogen pressure stabilization system to pressurize the coolant so that the coolant is transported under a stable pressure environment. However, the nitrogen pressure stabilization system can cause nitrogen to be supersaturated in the coolant. As a result, when the coolant passes through the impeller 30, due to the effect of the impeller 30 on the coolant, some nitrogen will precipitate and accumulate in the impeller 30 area, thereby accumulating to form air masses. The air masses not only hinder the normal flow of the fluid, affect the fluid flow pattern, and reduce the efficiency of the nuclear reactor shield pump, but also generate shock waves when the air masses rupture, forming cavitation.

[0045] To this end, the exhaust structure also includes an exhaust pipe 40, and a main shaft exhaust hole 21 is formed on the drive shaft 20. One end of the exhaust pipe 40 extends out of the motion chamber 11, and the other end is connected to the main shaft exhaust hole 21. Blade exhaust holes 32 are formed on the surface of the blades 31 of at least one impeller 30, and the blade exhaust holes 32 are connected to the main shaft exhaust hole 21. That is, the blade exhaust holes 32 are connected to the exhaust pipe 40 through the main shaft exhaust hole 21.

[0046] Beneficial effect: When the drive shaft 20 drives the impeller 30 to rotate, when nitrogen is precipitated at the impeller 30, the nitrogen will enter the blade exhaust holes 32 on the surface of the fan blade 31. The nitrogen then enters the main shaft exhaust hole 21 through the blade exhaust hole 32. Since the drive shaft 20 generates a centrifugal force during rotation, the centrifugal force drives the nitrogen in the blade exhaust hole 32 into the exhaust pipe 40 and is discharged from the exhaust pipe 40 to the outside atmosphere. In this way, the timely discharge and treatment of nitrogen can be achieved through the exhaust holes of the fan blade 31, the main shaft exhaust hole 21, and the exhaust pipe 40, which greatly improves the stability of the depressurization operation of the nuclear reactor shield pump and ensures the safe operation of the nuclear reactor shield pump.

[0047] It should be noted that, depending on the actual situation, it can be selected that only one of the fan blades 31 is provided with a blade exhaust hole 32, and the other fan blades 31 are not provided with a blade exhaust hole 32, or each fan blade 31 can be provided with a blade exhaust hole 32, which is not limited here.

[0048] In some embodiments of the present application, the exhaust structure further includes a fastener 33, which is provided at one end of the drive shaft 20 where the impeller 30 is provided, and is used to secure the impeller 30 to the drive shaft 20. Specifically, the fastener 33 is fixed to the center of the blades 31, and during actual use, in addition to nitrogen precipitated at the blades 31, some nitrogen will also precipitate at the center of the impeller 30. To this end, a central exhaust hole 34 is provided on the end of the fastener 33 away from the drive shaft 20, and the central exhaust hole 34 is connected to the main shaft exhaust hole 21.

[0049] Beneficial effect: the nitrogen precipitated at the center of the impeller 30 will enter the main shaft exhaust hole 21 through the central exhaust hole 34, and finally enter the exhaust pipe 40 through the main shaft exhaust hole 21 and be discharged from the motion chamber 11, so that the nitrogen precipitated at the center of the impeller 30 can be quickly discharged through the exhaust pipe 40, thereby avoiding the precipitation of nitrogen in the center of the impeller 30 to affect the normal operation of the nuclear reactor shield pump.

[0050] In some embodiments, the blade exhaust holes 32 are located on the side of the impeller 30 facing the fastener 33. During actual use, since the side of the impeller 30 facing the fastener 33 is primarily used to stir the coolant, nitrogen will primarily precipitate on the side of the impeller 30 facing the fastener 33. Thus, locating the impeller exhaust holes 32 on the side of the impeller 30 facing the fastener 33 facilitates the entry of nitrogen into the impeller exhaust pipe 32 and ultimately discharge from the exhaust pipe 40.

[0051] In some embodiments, the drive shaft 20 has a threaded hole 22 defined on one end surface located within the motion chamber 11. The threaded hole 22 communicates with the spindle exhaust hole 21. The fastener 33 is a bolt 36 threadedly engaged with the threaded hole 22, and a central exhaust hole 34 extends through the bolt 36 along the axis of the threaded hole 22. Thus, when the bolt 36 is installed in the threaded hole 22, the central exhaust hole 34 communicates with the spindle exhaust hole 21 through the threaded hole 22, allowing nitrogen gas at the center of the impeller 30 to enter the threaded hole 22 from the central exhaust hole 34, then into the central exhaust hole 34, and finally be discharged through the exhaust pipe 40.

[0052] Beneficial effect: by setting the threaded hole 22 on the end face of the drive shaft 20, the processing difficulty of the threaded hole 22 can be reduced, and the bolt 36 can also be used to process the center exhaust hole 34 separately. When the bolt 36 is threadedly connected to the threaded hole 22, the center exhaust hole 34 will be connected to the threaded hole 22, further reducing the difficulty of installation and processing.

[0053] Specifically, in one embodiment, the impeller 30 is provided with a mounting hole 35 and a keyway located on the inner wall of the mounting hole 35. The exhaust structure further includes a flat key 23 provided on the drive shaft 20, and the flat key 23 extends in a direction parallel to the axis of the drive shaft 20. The drive shaft 20 is passed through the mounting hole 35, and the flat key 23 is disposed in the keyway. The drive shaft 20 further includes a limiting step 24. The limiting step 24 and the bolt 36 are spaced apart along the axis of the drive shaft 20, and the impeller 30 is disposed between the limiting step 24 and the bolt 36. In this manner, the bolt 36 and the limiting step 24 limit and secure the impeller 30 in the axial direction of the drive shaft 20. When the drive shaft 20 rotates, the flat key 23 drives the impeller 30 to rotate together, thereby achieving the fixation and drive of the impeller 30.

[0054] Beneficial effect: the impeller 30 is fixed and driven by means of the flat key 23 and the bolt 36, which reduces the difficulty of installing the impeller 30 while ensuring the transmission efficiency. At the same time, components such as the flat key 23 and the bolt 36 are common and universal parts, which is beneficial to the later maintenance and replacement of the nuclear reactor shield pump.

[0055] Furthermore, the blade exhaust holes 32 on the fan blades 31 extend through the inner wall of the mounting hole 35. A connecting hole 25 is formed on the circumferential sidewall of the drive shaft 20. These connecting holes 25 connect the blade exhaust holes 32 and the spindle exhaust hole 21. In this way, nitrogen released near the fan blades 31 can pass through the blade exhaust holes 32 into the corresponding connecting holes 25, and finally enter the spindle exhaust hole 21 through the connecting opening and be discharged from the exhaust pipe 40.

[0056] It should be noted that the number of communication holes 25 can be determined based on the number of blade exhaust holes 32. That is, when only one blade 31 is provided with a blade exhaust hole 32, there is also only one communication hole 25. When multiple blades 31 are provided with blade exhaust holes 32, that is, there are multiple blade exhaust holes 32, there are also multiple communication holes 25. Each communication hole 25 corresponds to one of the blade exhaust holes 32 and is interconnected. All communication holes 25 are interconnected with the main shaft exhaust hole 21.

[0057] Advantageously, when the impeller 30 is mounted on the drive shaft 20 using the flat key 23 and bolts 36, the flat key 23 and keyway limit the impeller 30, allowing it to be accurately mounted in a fixed position on the drive shaft 20, thereby aligning and connecting the communication port with the corresponding blade exhaust hole 32. This allows the communication port to communicate with the corresponding blade exhaust hole 32 as soon as the impeller 30 is installed, eliminating the need to separately align the communication port and blade exhaust hole 32, thus saving installation steps.

[0058] In some embodiments of the present application, the exhaust structure further includes a sleeve 50, which includes a sliding hole 51. The drive shaft 20 is inserted into the sliding hole 51 so that the sleeve 50 is sleeved on the drive shaft 20. A gas collecting chamber 52 is formed inside the sleeve 50, and the exhaust pipe 40 is connected to the gas collecting chamber 52. An annular hole 53 is formed on the inner wall of the sliding hole 51. The annular hole 53 is connected to the gas collecting chamber 52 and is arranged around the circumference of the drive shaft 20. An air outlet 26 is provided on the circumferential side wall of the drive shaft 20. The air outlet 26 is connected to the annular hole 53, and when the drive shaft 20 rotates around its own axis, the air outlet 26 moves along the annular hole 53.

[0059] As a result, when the drive shaft 20 drives the impeller 30 to rotate, the air outlet 26 moves along the annular hole 53, thereby maintaining communication with the annular hole 53 during the rotation of the drive shaft 20. Specifically, the annular holes 53 are connected end to end. When the drive shaft 20 rotates one circle, the air outlet 26 moves along the annular hole 53 one circle. This ensures that the air outlet 26 always maintains communication with the annular hole 53 during the continuous rotation of the drive shaft 20, thereby ensuring that the nitrogen in the main shaft exhaust hole 21 can be stably discharged into the gas collecting chamber 52 through the air outlet 26.

[0060] Beneficial effect: By providing the gas collecting chamber 52 on the shaft sleeve 50, the nitrogen entering the main shaft exhaust hole 21 is discharged into the gas collecting chamber 52 under the centrifugal force generated by the rotation of the drive shaft 20, and then discharged through the gas collecting chamber 52 and the external exhaust pipe 40. The gas collecting chamber 52 meets the need for collecting gas after it is discharged from the impeller 30, preventing the gas from continuing to enter the subsequent motor cavity and affecting the operation of the pump.

[0061] In some embodiments, a movable protrusion 27 is provided on the drive shaft 20. The movable protrusion 27 is disposed through the annular hole 53, and a portion of the movable protrusion 27 is located in the gas collecting chamber 52. The air outlet is located on the portion of the movable protrusion 27 located in the gas collecting chamber 52. Thus, when the drive shaft 20 rotates, the movable protrusion 27 moves along the annular hole 53. Because the air outlet is located on the portion of the movable protrusion 27 that extends into the gas collecting chamber 52, the air outlet can be stably connected to the gas collecting chamber 52.

[0062] Beneficial effect: by arranging the air outlet at the part of the movable protrusion 27 extending into the air collecting chamber 52, the air outlet can be stably connected to the air collecting chamber 52, ensuring that the nitrogen in the spindle exhaust hole 21 can be stably discharged into the air collecting chamber 52 through the air outlet 26.

[0063] In some embodiments of the present application, the motion chamber 11 includes a flywheel sub-chamber 12 and an impeller sub-chamber 13, the impeller 30 is disposed in the impeller sub-chamber 13, the drive shaft 20 is passed through the flywheel sub-chamber 12 and the impeller sub-chamber 13, and the shaft sleeve 50 and the exhaust pipe 40 are both disposed in the flywheel sub-chamber 12. Furthermore, the exhaust structure also includes a flywheel 60, which is disposed on the drive shaft 20 and is located in the flywheel sub-chamber 12. The flywheel 60 is used to provide an inertial force for the rotation of the drive shaft 20. When the shield pump of the nuclear reactor suddenly loses power, the rotational kinetic energy stored in the flywheel 60 will continue to drive the drive shaft 20 and the impeller 30 to rotate for a period of time, which is called "idling". This inertial operation can maintain coolant circulation, gain valuable shutdown buffer time for the system, and prevent the nuclear reactor from causing danger due to instantaneous loss of cooling.

[0064] Beneficial effect: by arranging the shaft sleeve 50 and the exhaust pipe 40 in the flywheel sub-cavity 12, the shaft sleeve 50 and the exhaust pipe 40 can be separated from the space where the impeller 30 is located, thereby reducing the influence of the shaft sleeve 50 and the exhaust pipe 40 on the rotation of the impeller 30 and ensuring the driving efficiency of the impeller 30 on the coolant.

[0065] In some embodiments of the present application, the exhaust structure further includes an exhaust valve 41, which is provided in the cavity assembly 10 and is located outside the motion chamber 11. The exhaust valve 41 is connected to the exhaust pipe 40. The exhaust valve 41 is used to open only when the gas-liquid pressure in the exhaust pipe 40 reaches a certain level, so that the exhaust pipe 40 is connected to the atmosphere. Specifically, the exhaust valve 41 is provided at the highest point of the exhaust pipe 40, and after the nitrogen in the coolant is precipitated and enters the gas collecting chamber 52, it will continue to gather toward the highest point of the exhaust pipe 40 under the action of the centrifugal force of the drive shaft 20 until the gas pressure gathered at the highest point of the exhaust pipe 40 reaches a certain level, and then the exhaust valve 41 will open to discharge the gas.

[0066] Beneficial effect: Since the motion chamber 11 is filled with coolant, if nitrogen is discharged directly through the exhaust pipe 40, it will carry a portion of coolant with it and overflow from the exhaust pipe 40 each time it is discharged, resulting in coolant waste. However, by providing the exhaust valve 41, the gas will first accumulate at the exhaust valve 41, and the exhaust valve 41 will not be opened until the gas accumulates to a certain level, thereby reducing the number of gas discharges and further reducing the coolant carried out when the gas is discharged, thereby reducing coolant waste.

[0067] The following combination Figure 2 and Figure 3 The working process of the exhaust structure of the nuclear reactor shield pump of this application is described as follows:

[0068] A central exhaust hole 34 is machined into bolt 36, allowing nitrogen gas near the center of impeller 30 to escape through this hole and enter the main shaft center hole. A blade 31 exhaust hole is also machined at the inlet of impeller 30, allowing nitrogen gas at the impeller 30 entrance to escape through the blade 31 exhaust hole, into the connecting hole, and ultimately into the main shaft center hole. The gas in the main shaft center hole eventually enters nitrogen gas collection chamber 52 due to the centrifugal force generated by the rotation of drive shaft 20, and then exits the system through exhaust pipe 40 connected to gas collection chamber 52.

[0069] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A nuclear reactor shield pump, characterized in that: The nuclear reactor shield pump includes an exhaust structure, and the exhaust structure includes: A cavity assembly (10) forming a motion chamber (11); A drive shaft (20), one end of which is connected to the rotor of the nuclear reactor shield pump, and the other end of which extends into the motion chamber (11), and a main shaft exhaust hole (21) is formed on the drive shaft (20); an impeller (30) disposed in the motion chamber (11) and connected to the drive shaft (20), the impeller (30) having a plurality of blades (31) circumferentially arranged around the drive shaft (20), at least one of the blades (31) having a blade exhaust hole (32) formed on its surface, the blade exhaust hole (32) being in communication with the main shaft exhaust hole (21); An exhaust pipe (40) has one end extending out of the motion chamber (11) and the other end communicating with the main shaft exhaust hole (21).

2. The nuclear reactor shield pump according to claim 1, characterized in that: The exhaust structure further includes a fastener (33), the fastener (33) being provided at one end of the drive shaft (20) where the impeller (30) is provided, and being used to fix the impeller (30) to the drive shaft (20); A central exhaust hole (34) is provided on one end of the fastener (33) away from the drive shaft (20), and the central exhaust hole (34) is connected to the main shaft exhaust hole (21).

3. The nuclear reactor shield pump according to claim 2, characterized in that: The blade exhaust hole (32) is located on a side surface of the impeller (30) facing the fastener (33).

4. The nuclear reactor shield pump according to claim 2, characterized in that: The drive shaft (20) is provided with a threaded hole (22) on one end surface located in the motion chamber (11), and the threaded hole (22) is communicated with the main shaft exhaust hole (21); The fastener (33) is a bolt (36), the bolt (36) is threadedly connected to the threaded hole (22), and the central exhaust hole (34) passes through the bolt (36) along the axial direction of the threaded hole (22).

5. The nuclear reactor shield pump according to claim 4, characterized in that: The impeller (30) is provided with a mounting hole (35) and a keyway located on the inner wall of the mounting hole (35); the exhaust structure further comprises a flat key (23) provided on the drive shaft (20); the extension direction of the flat key (23) is parallel to the axis of the drive shaft (20); the drive shaft (20) is passed through the mounting hole (35), and the flat key (23) is provided in the keyway; The drive shaft (20) further includes a position-limiting step portion (24), wherein the position-limiting step portion (24) and the bolt (36) are arranged at intervals along the axial direction of the drive shaft (20), and the impeller (30) is arranged between the position-limiting step portion (24) and the bolt (36).

6. The nuclear reactor shield pump according to claim 5, characterized in that: The blade exhaust hole (32) on the fan blade (31) extends through the inner wall of the mounting hole (35), and a connecting hole (25) is provided on the circumferential side wall of the drive shaft (20), wherein the connecting hole (25) is connected to the blade exhaust hole (32) and the main shaft exhaust hole (21).

7. The nuclear reactor shield pump according to claim 1, characterized in that: The exhaust structure further comprises a shaft sleeve (50), the shaft sleeve (50) comprising a sliding hole (51), the drive shaft (20) passing through the sliding hole (51), an air collecting cavity (52) formed inside the shaft sleeve (50), and the exhaust pipe (40) being in communication with the air collecting cavity (52); An annular hole (53) is provided on the inner wall of the sliding hole (51), the annular hole (53) is connected to the gas collecting chamber (52), and is arranged around the circumference of the driving shaft (20). An air outlet hole (26) is provided on the circumferential side wall of the driving shaft (20), the air outlet hole (26) is connected to the annular hole (53), and when the driving shaft (20) rotates around its own axis, the air outlet hole (26) moves along the annular hole (53).

8. The nuclear reactor shield pump according to claim 7, characterized in that: A movable protrusion (27) is provided on the driving shaft (20), the movable protrusion (27) is passed through the annular hole (53), and a portion of the movable protrusion (27) is located in the gas collecting cavity (52), and the air outlet hole (26) is located on the portion of the movable protrusion (27) located in the gas collecting cavity (52).

9. The nuclear reactor shield pump according to claim 8, characterized in that: The motion chamber (11) includes a flywheel sub-chamber (12) and an impeller sub-chamber (13), the impeller (30) is arranged in the impeller sub-chamber (13), the drive shaft (20) passes through the flywheel sub-chamber (12) and the impeller sub-chamber (13), and the shaft sleeve (50) and the exhaust pipe (40) are both arranged in the flywheel sub-chamber (12); The exhaust structure further comprises a flywheel (60), wherein the flywheel (60) is provided on the drive shaft (20) and is located in the flywheel sub-cavity (12).

10. The nuclear reactor shield pump according to claim 1, characterized in that: The exhaust structure further comprises an exhaust valve (41), wherein the exhaust valve (41) is provided on the cavity assembly (10) and is located outside the motion chamber (11), and the exhaust valve (41) is connected to the exhaust pipe (40).

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