Shielded reactor coolant pump

Abstract

The invention relates to the technical field of nuclear reactor coolant pumps, and particularly provides a shielding type reactor coolant pump which comprises a pump shell, a pump body, a pump cover, a pump cover and a pump cover, and the pump shell is internally provided with a containing cavity, an inlet and an outlet; the suction guide pipe is located at an inlet of the pump shell; the pump core bag is detachably installed in the containing cavity, and a hydraulic channel is formed between the pump shell and the pump core bag; the two ends of the hydraulic channel are connected to the suction guide pipe and the outlet respectively. The pump core package is used for pressurizing cooling water in the hydraulic channel and then discharging the cooling water through the outlet. The invention aims to solve the problem that a pump shell of an existing coolant pump cannot be matched with pump core packages of different models for installation, the pump core packages and the pump shell can be detachably installed, the pump core packages of different models can be matched with the structure of the same pump shell, and the production requirements of a nuclear reactor at different stages are met; meanwhile, the pump shell can be reused, the use cost of the coolant pump is effectively reduced, and the use experience of a user is improved.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear reactor coolant pumps, and in particular provides a shielded reactor coolant pump. Background Art

[0002] Reactor coolant pump is one of the key equipment of nuclear island. At present, the reactor coolant pump used in domestic CAP series reactors is mainly shielded electric pump. The existing shielded electric pump casing is made of austenitic stainless steel integrated casting, with an annular chamber inside. The suction duct is directly connected by bolts at the pump casing inlet. The pump casing, suction duct and pump core hydraulic components (impeller and guide vane) cooperate to form the hydraulic flow channel in the pump casing cavity.

[0003] However, since one type of reactor coolant pump cannot meet the production requirements of different stages, in order to meet different production needs and save costs at the same time, a coolant pump that can detachably install the pump core package and the pump casing is needed. However, due to the limitations of the fixed structural dimensions of the pump casing, the interface dimensions of different types of shielded electric pump core packages and pump casings are inconsistent, resulting in the inability of existing pump core packages to be adapted to different units. At the same time, the existing pump body is equipped with an external heat exchanger to provide cooling water for the motor, which makes the on-site installation of the main pump more difficult and severely limits the possibility of using shielded electric pumps on different units. Therefore, a coolant pump is needed to solve the above problems. Summary of the invention

[0004] An object of the present invention is to provide a reactor coolant pump in which a pump casing and a pump core package are detachably mounted.

[0005] Another object of the present invention is to provide a cooling system in which a coolant pump and a heat exchanger are separately arranged to improve the environmental adaptability of the equipment.

[0006] To achieve the above object, the present invention provides a shielded reactor coolant pump, comprising:

[0007] A pump housing, which includes a receiving cavity, an annular outer flow channel located outside the receiving cavity, and a hydraulic flow channel located inside the receiving cavity;

[0008] A suction conduit, which is located at the opening of the pump housing, and whose two ends are respectively connected with the annular outer flow channel and the hydraulic flow channel to guide the cooling water of the annular outer flow channel to the hydraulic flow channel;

[0009] A pump core package is detachably mounted in the accommodating cavity so as to be cooled by cooling water in the hydraulic flow channel.

[0010] Furthermore, the shielded reactor coolant pump also includes: a fixing ring, which is sleeved on the inner wall of the pump casing and fixedly connected to the pump casing; a first fastener, used to fasten the fixing ring to the suction duct; and the pump casing is configured to adapt to different models of the pump core package by adjusting the size of the fixing ring and the tightness of the first fastener.

[0011] Furthermore, the fixing ring is fixedly connected to the pump casing by welding.

[0012] Furthermore, a mounting groove is provided on the inner side wall of the pump housing, and the fixing ring can be fixedly installed in the mounting groove.

[0013] Furthermore, the pump core package includes an impeller, a locking bolt, an impeller shaft, a guide vane and a shielded motor connected in sequence, and the hydraulic flow channel is formed between the impeller, the locking bolt and the guide vane; the pump core package also includes a mouth ring and a second fastener, the mouth ring is sleeved on the outside of the impeller and fixedly connected to the guide vane, and the second fastener is used to fasten the impeller to the hydraulic flow channel; and a hydraulic seal is formed between the mouth ring and the impeller; the pump casing is configured to adapt to different models of the pump core packages by adjusting the size of the mouth ring and the tightness of the second fastener.

[0014] Further, either or both of the first fastener and the second fastener are configured as screws; or, either or both of the first fastener and the second fastener are configured as bolts.

[0015] Furthermore, the fixing ring and the mouth ring are both made of nickel-based material in one piece.

[0016] Furthermore, the shielded reactor coolant pump is suitable for pressure vessels of CPA series reactor types.

[0017] Furthermore, a shielded reactor cooling system comprises a heat exchanger and the shielded reactor coolant pump as described above; the heat exchanger is connected to the shielded reactor coolant pump via a pipeline to perform heat exchange on the water flow after circulating therein.

[0018] Furthermore, the pump casing includes a cooling water inlet and a circulating water outlet, the cooling water inlet is connected to the cooling water source and / or the outlet fluid of the cooling water heat exchanger through a pipe to guide the cooling water to the annular outer flow channel; the cooling water outlet is connected to the water inlet of the cooling water heat exchanger to exchange heat with the circulated water flow.

[0019] Based on the foregoing description, those skilled in the art will understand that, in the aforementioned technical solution of the present invention, by arranging the suction duct at the inlet of the pump casing, the two ends of the hydraulic flow channel are respectively connected to the suction duct and the pump casing outlet, and the pump core package and the pump casing are made detachable and installable, so that pump core packages of different models can be adapted to the structure of the same pump casing to meet the production requirements of different stages of the nuclear reactor; at the same time, the pump casing can be reused, which effectively reduces the use cost of the coolant pump and improves the user experience.

[0020] Furthermore, by installing the heat exchanger and the shielded reactor coolant pump separately, the coolant pump can be flexible in the spatial environment, reducing the difficulty of on-site installation of the pump casing and the pump core package, and further improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, some embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood by those skilled in the art that the same reference numerals indicate the same or similar components or parts in different drawings; the drawings of the present invention are not necessarily drawn to scale.

[0022] In the attached figure:

[0023] Figure 1 is a schematic diagram of the structure of a shielded reactor coolant pump in some embodiments of the present invention;

[0024] Figure 2 It is a schematic diagram of the structure of a shielded reactor coolant pump in other embodiments of the present invention.

[0025] Reference numerals:

[0026] 100. Shielded reactor coolant pump;

[0027] 1. Pump casing; 2. Fixing ring; 3. First fastener; 4. Suction duct; 5. Second fastener; 6. Mouth ring; 7. Locking bolt; 8. Impeller shaft; 9. Impeller; 10. Guide vane; 11. Shielded motor. DETAILED DESCRIPTION

[0028] It should be understood by those skilled in the art that the embodiments described below are only some embodiments of the present invention, rather than all embodiments of the present invention, and these embodiments are intended to explain the technical principles of the present invention, rather than to limit the protection scope of the present invention. Based on the embodiments provided by the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should still fall within the protection scope of the present invention.

[0029] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "top", "bottom", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0030] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Refer to the following Figure 1 to Figure 2 The shielded reactor coolant pump in some embodiments of the present invention is described in detail. Figure 1 is a schematic diagram of the structure of a shielded reactor coolant pump in some embodiments of the present invention; Figure 2 It is a schematic diagram of the structure of a shielded reactor coolant pump in other embodiments of the present invention.

[0032] It should be noted that, for the convenience of description and to enable those skilled in the art to quickly understand the technical solution of the present invention, the following text only describes the technical features that are strongly related (directly or indirectly related) to the technical problem and / or technical concept to be solved by the present invention, and will not describe the technical features that are weakly related to the technical problem and / or technical concept to be solved by the invention. Since the technical features with a weaker degree of correlation belong to the common knowledge in the field, even if the present invention does not describe the features with a weaker degree of correlation, it will not lead to insufficient disclosure of the present invention.

[0033] like Figure 1As shown, in some embodiments of the present invention, a shielded reactor coolant pump 100 is provided. The shielded reactor coolant pump 100 in the present invention is suitable for pressure vessels of the CPA series reactor type. The pump core pack of the shielded reactor coolant pump can be detachably installed in the pump housing 1, so that the operator can replace the pump core packs of different models according to the scene requirements, which is highly practical; at the same time, when the pump core pack needs to be replaced, the operator can quickly disassemble it, reduce the maintenance cost of the equipment and improve the reuse rate of the equipment, which can reduce the use cost of the operator to a certain extent and improve the user experience.

[0034] It should be noted that the pump casing 1 and the pump core package together form a hydraulic flow channel, and the two ends of the hydraulic flow channel are respectively connected to the inlet and outlet of the pump casing 1. The pump core package is arranged in the pump casing 1, and is used to pressurize the cooling water in the hydraulic flow channel and then guide it out through the outlet of the pump casing 1. Specifically, due to the complex internal structure of the pump core package, the hydraulic flow channel is limited by its structure and cannot be adapted to pump core packages of different models. This leads to the problem that the structural stability of the pump casing 1 and the pump core package of the coolant pump of different models of nuclear reactors cannot be guaranteed after installation. Since the coolant pump core package runs at high speed in the working state, structural incompatibility can easily cause equipment damage and reduce the service life of the equipment. Therefore, in order to realize the detachable installation of the pump casing 1 and the pump core package and improve its adaptability and practicality, it is necessary to consider the structural adaptation of the connection between the water flow channel of the pump casing 1 and the pump core package.

[0035] The shielded reactor coolant pump 100 includes a pump housing 1, a suction conduit 4 and a pump core package, wherein the pump housing 1 includes a receiving chamber, an inlet and an outlet. The suction conduit 4 is located at the opening of the pump housing 1, and the two ends of the suction conduit 4 are respectively connected to the annular outer flow channel and the hydraulic flow channel to guide the cooling water of the annular outer flow channel to the hydraulic flow channel. The pump core package is detachably installed in the receiving chamber to pressurize the cooling water of the hydraulic flow channel and then throw the cooling water out through the outlet on the pump housing 1.

[0036] Optionally, the pump housing 1 is configured as a worm gear structure as a whole, and the guide directions of the inlet and the outlet are arranged vertically as a whole.

[0037] like Figure 1As shown, in order to make the connection between the suction duct 4 and the pump casing 1 match with different types of pump core packages, in other embodiments of the present invention, a fixing ring 2 and a first fastener 3 are added to the shielded reactor coolant pump 100, and the fixing ring 2 is sleeved on the inner wall of the pump casing 1 and fixedly connected to the pump casing 1. The first fastener 3 is used to fasten the fixing ring 2 to the suction duct 4. The pump casing 1 is configured to adapt to different types of pump core packages by adjusting the size of the fixing ring 2 and the tightness of the first fastener 3. Specifically, the operator can select fixing rings 2 of different sizes according to different types of pump core packages, and then adjust the tightness between the fixing ring 2 and the suction duct 4 through the first fastener 3 to adjust the tightness between the impeller 9 and the suction pipe.

[0038] In some examples of this embodiment, the fixing ring 2 is fixedly connected to the pump casing 1 by welding.

[0039] In other examples of this embodiment, a mounting groove is provided on the inner side wall of the pump housing 1, and the fixing ring 2 can be fixedly installed in the mounting groove. Specifically, the width of the mounting groove is greater than the width of the fixing ring 2, and the fixing ring 2 can be installed in the mounting groove by screws or bolts. When the pump core pack needs to be replaced, the operator can loosen the screws or bolts to remove the fixing ring 2, so as to select fixing rings 2 of different sizes according to different models of pump core packs.

[0040] The pump core package includes an impeller 9, a locking bolt 7, an impeller shaft 8, a guide vane 10 and a shielded motor 11 connected in sequence, and a hydraulic flow channel is formed between the impeller 9, the locking bolt 7, the guide vane 10 and the pump housing 1. The present invention connects the impeller 9, the guide vane 10 and the shielded motor 11 together only through an impeller shaft 8. The cooling water enters the hydraulic flow channel from the suction duct 4 at the inlet of the pump body. After the cooling water is pressurized by the high-speed rotation of the impeller 9, the high-pressure cooling water is guided to the outlet of the pump housing 1 through the guide vane 10 to guide the pressurized cooling water out.

[0041] like Figure 2 As shown, in order to further improve the structural stability between the pump core package and the pump housing 1, in some other embodiments of the present invention, the pump core package further includes a mouth ring 6 and a second fastener 5, the mouth ring 6 is sleeved on the outside of the impeller 9 and fixedly connected to the guide vane 10, and the second fastener 5 is used to fasten the impeller 9 to the hydraulic flow channel. A hydraulic seal is formed between the mouth ring 6 and the impeller 9, so that the impeller 9 runs at a high speed in the working state, and the mouth ring 6 and the hydraulic flow channel are hydraulically sealed, thereby improving the sealing and structural stability during the operation of the equipment.

[0042] The pump housing 1 is also configured to adapt to different types of pump core packs by adjusting the size of the mouth ring 6 and the degree of tightening of the second fastener 5. Specifically, the operator can select mouth rings 6 of different sizes according to different types of pump core packs as needed, and improve the overall structural stability of the device by adjusting the tightness of the connection between the impeller 9 and the hydraulic channel.

[0043] Optionally, any one or both of the first fastener 3 and the second fastener 5 are configured as screws. Alternatively, any one or both of the first fastener 3 and the second fastener 5 are configured as bolts.

[0044] Specifically, the fixing ring 2 and the mouth ring 6 are both made of nickel-based material in one piece.

[0045] In other embodiments of the present invention, a shielded reactor cooling system is also provided, comprising a heat exchanger and any of the shielded reactor coolant pumps 100 described above. Since the heat exchanger and the pump body in the existing shielded reactor coolant pump 100 are installed through a bracket structure, that is, the heat exchanger is installed above the coolant pump through the bracket structure, the coolant pump is limited in space structure, which is not conducive to disassembly / installation of the pump core package. Therefore, the present invention separates the heat exchanger from the shielded reactor coolant pump 100, so that the heat exchanger is installed on the wall of the steam generator compartment of the shielded reactor coolant pump 100, thereby reducing the space requirement for the main pump installation and reducing the difficulty of on-site installation of the main pump.

[0046] Since the motor of the shielded reactor coolant pump 100 generates a large amount of heat during high-speed operation, in order to ensure the stable operation of the shielded reactor coolant pump 100, the present invention connects the heat exchanger to the shielded reactor coolant pump 100 through a pipeline, so that the heat generated by the motor is exchanged with the heat exchanger through circulating water to control the temperature and flow of the cooling water.

[0047] It will be understood by those skilled in the art that, by arranging the suction duct 4 at the inlet of the pump casing 1, the two ends of the hydraulic channel are respectively connected to the suction duct 4 and the outlet of the pump casing 1, and the pump core package and the pump casing 1 are detachably installed, so that pump core packages of different models can be adapted to the structure of the same pump casing 1 to meet the production requirements of the nuclear reactor at different stages; at the same time, the pump casing 1 can be reused, which effectively reduces the use cost of the coolant pump and improves the user experience.

[0048] Furthermore, by installing the heat exchanger and the shielded reactor coolant pump separately, the coolant pump is flexible in the spatial environment, reducing the difficulty of on-site installation of the pump casing 1 and the pump core package, and further improving the user experience.

[0049] So far, the technical solution of the present invention has been described in combination with the above multiple embodiments, but it is easy for those skilled in the art to understand that the protection scope of the present invention is not limited to these specific embodiments. Without departing from the technical principles of the present invention, those skilled in the art can split and combine the technical solutions in the above embodiments, and can also make equivalent changes or replacements to the relevant technical features. Any changes, equivalent replacements, improvements, etc. made within the technical concept and / or technical principles of the present invention will fall within the protection scope of the present invention.

Claims

1. A shielded reactor coolant pump, characterized in that: include: A pump housing having a receiving chamber, an inlet and an outlet therein; a suction conduit located at the inlet of the pump housing; A pump core package is detachably installed in the accommodating cavity, and a hydraulic channel is formed between the pump housing and the pump core package; the two ends of the hydraulic channel are respectively connected to the suction duct and the outlet; the pump core package is used to pressurize the cooling water in the hydraulic channel and discharge it through the outlet.

2. The shielded reactor coolant pump according to claim 1, characterized in that: Also includes: A fixing ring, which is sleeved on the inner side wall of the pump housing and fixedly connected to the pump housing; A first fastener is used to fasten the fixing ring to the suction conduit; and The pump housing is configured to adapt to different models of pump core packages by adjusting the size of the fixing ring and the tightening degree of the first fastener.

3. The shielded reactor coolant pump according to claim 2, characterized in that: The fixing ring is fixedly connected to the pump casing by welding.

4. The shielded reactor coolant pump according to claim 2, characterized in that: The inner side wall of the pump housing is provided with a mounting groove, and the fixing ring can be fixedly installed in the mounting groove.

5. The canned reactor coolant pump according to claim 2, characterized in that: The pump core package includes a locking bolt, an impeller, an impeller shaft, a guide vane and a shielded motor connected in sequence, and the hydraulic flow channel is formed between the impeller, the locking bolt, the guide vane and the pump casing; The pump core package further includes a mouth ring and a second fastener, wherein the mouth ring is sleeved on the outer side of the impeller and fixedly connected to the guide vane, and the second fastener is used to fasten the impeller to the hydraulic flow channel; and a hydraulic seal is formed between the mouth ring and the impeller; The pump housing is configured to adapt to different models of the pump core packages by adjusting the size of the mouth ring and the tightening degree of the second fastener.

6. The canned reactor coolant pump according to claim 5, characterized in that: Either or both of the first fastener and the second fastener are configured as screws; or, Either or both of the first fastener and the second fastener are configured as bolts.

7. The canned reactor coolant pump according to claim 5, characterized in that: The fixing ring and the mouth ring are both made of nickel-based material in one piece.

8. The canned reactor coolant pump according to any one of claims 1 to 7, characterized in that: The shielded reactor coolant pump is suitable for CPA series reactor type pressure vessels.

9. A cooling system for a shielded reactor, characterized in that: It comprises a heat exchanger and the shielded reactor coolant pump according to any one of claims 1 to 8; the heat exchanger is connected to the shielded reactor coolant pump through a pipeline to perform heat exchange on the shielded reactor coolant pump.

10. The shielded reactor cooling system according to claim 9, characterized in that: The pump housing includes a circulating water inlet and a circulating water outlet, wherein the circulating water inlet is in fluid communication with a water outlet of the heat exchanger through a pipeline to guide cooling water to the hydraulic flow channel; The cooling water outlet is communicated with the water inlet of the cooling water heat exchanger to exchange heat with the circulated water flow.

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