A nuclear power plant container internal foreign object fishing device and fishing method

Abstract

The application provides a nuclear power plant container foreign matter fishing device and fishing method, which comprises a foreign matter fishing main guide rod, a first aluminum plastic pipe, a second aluminum plastic pipe, a first nylon rope, a push rod, a second nylon rope, a foreign matter cage, a third nylon rope, a camera, a endoscope and a four-corner grab. The first aluminum plastic pipe is fixed on the foreign matter fishing main guide rod and is used as a guide pipe of the endoscope. The lower end of the first aluminum plastic pipe is bent to ensure normal passing of the endoscope. The second aluminum plastic pipe is fixedly connected with the first aluminum plastic pipe and is fixed in parallel on the foreign matter fishing main guide rod. The lower end of the second aluminum plastic pipe is bent to ensure normal passing of the four-corner grab. One end of the first nylon rope is fixed at the bottom of the foreign matter fishing main guide rod. The application realizes the technical effect of guiding the endoscope and the grabbing tool by fixing two aluminum plastic pipes in parallel on the foreign matter fishing main guide rod and setting the lower end of the two aluminum plastic pipes to be bent.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of diesel generators for nuclear power plants, and particularly relates to a nuclear power plant container internal foreign object fishing device and a fishing method. BACKGROUND

[0002] A valve body of a 2RCP002VP valve of a reactor coolant system of a nuclear power unit such as Fuqing No. 2 unit is disassembled, and it is found that a valve seat disc spring is broken and a small half circle (about 170°, 90mm half-arc length) is missing. After the foreign object in the upstream and downstream pipelines of the 2RCP001 / 002VP valve and the stabilizer 2RCP001BA is investigated, it is confirmed that the missing disc spring of the 2RCP002VP is located on the lower support plate of the stabilizer 2RCP001BA, and the foreign object is in the primary loop. During operation, it may cause damage to the fuel assembly and the primary loop main equipment. The foreign object is located at the bottom of the stabilizer, and due to the limited internal space, the endoscope and the grabber cannot be normally turned, and it is extremely difficult to fish by using the conventional method. SUMMARY

[0003] Therefore, the embodiments of the application aim to provide a nuclear power plant container internal foreign object fishing device and a fishing method, by fixing two aluminum plastic pipes side by side on the foreign object fishing main guide rod and bending the lower ends of the two aluminum plastic pipes, to solve the problem of fishing the foreign object in the nuclear power plant container, narrow space and high dose area.

[0004] The first aspect of the application provides a nuclear power plant container internal foreign object fishing device, which comprises a foreign object fishing main guide rod, a first aluminum plastic pipe, a second aluminum plastic pipe, a first nylon rope, a push rod, a second nylon rope, a foreign object cage, a third nylon rope, a camera, an endoscope and a four-corner grabber. The first aluminum plastic pipe is fixed on the foreign object fishing main guide rod, and is used as a guide pipe for the endoscope. The lower end of the first aluminum plastic pipe is bent to ensure that the endoscope can pass normally. The second aluminum plastic pipe is fixedly connected with the first aluminum plastic pipe and is fixed side by side on the foreign object fishing main guide rod. The lower end of the second aluminum plastic pipe is bent to ensure that the four-corner grabber can pass normally. One end of the first nylon rope is fixed at the bottom of the foreign object fishing main guide rod. The push rod is used to pull part of the first nylon rope to the vertical position in the center of the container. The second nylon rope is used to pull the foreign object cage. The third nylon rope is used to pull and adjust the position of the camera. The camera is used to provide illumination and monitoring in the container. The endoscope is used to provide illumination and monitoring at the bottom of the container.

[0005] In one specific embodiment of the application, the lower ends of the first aluminum plastic pipe and the second aluminum plastic pipe are each bent by 155°.

[0006] In one specific embodiment of the application, the foreign object fishing main guide rod is assembled by a plurality of guide rods, and the two adjacent guide rods in the plurality of guide rods are linked by a pin shaft.

[0007] The second aspect of the present application provides a method for salvaging foreign objects in a nuclear power plant container, which comprises: opening a manhole of a pressurizer, installing a flange and a guide rail of the pressurizer; tying a third nylon rope in a foreign object salvaging device in a nuclear power plant container of an embodiment of the present application to a camera; connecting a camera system and an endoscope inspection system, turning on a built-in light tube and a monitoring screen after power is turned on; sending the camera to the central axis inside the pressurizer through the guide rail; adjusting the pitch angle of the camera to face vertically downward, and sending the camera to a position about 300mm above the central hole of the lower support plate of the electric heating element through the third nylon rope; adjusting the rotation and pitch of the camera, adjusting the camera angle, and confirming the position of the foreign object in the lower head area of ​​the pressurizer below the lower support plate of the electric heating element; monitoring the position of the foreign object throughout the process through the rotation angle of the camera and the endoscope monitoring screen; tying a first aluminum-plastic pipe and a second aluminum-plastic pipe to the center of the pressurizer; adjusting the rotation and pitch of the camera, and adjusting the camera angle; The tubes are fixed in parallel at the ends of the main guide rod for foreign body salvage, and the lower ends of the first aluminum-plastic tube and the second aluminum-plastic tube are bent; the first nylon rope is fixed at the bottom end of the main guide rod for foreign body salvage; the endoscope and the four-corner grabber are guided to the vicinity of the foreign body through the first aluminum-plastic tube and the second aluminum-plastic tube; the first nylon rope at the end of the main guide rod for foreign body salvage is tied to a fixed point or the operator's hand, and sent into the interior through the manhole of the stabilizer, and slowly descended to the center hole of the support plate under the electric heating element, and then the main guide rod for foreign body salvage is controlled to make the four-corner grabber enter the lower area of ​​the lower support plate; the foreign body cage is placed into the bottom of the stabilizer with the second nylon rope; under the monitoring positioning of the endoscope monitoring screen, the foreign body is grabbed with the four-corner grabber; after grabbing the foreign body, the foreign body salvage main guide rod is slowly lifted up and the foreign body is placed in the foreign body cage; the foreign body cage is slowly lifted up and the foreign body is taken out of the stabilizer, and the foreign body is placed in a high-pressure container prepared in advance.

[0008] In one embodiment of the present application, before or simultaneously securing the first and second aluminum-plastic tubes side by side to the ends of the foreign object salvage main guide rod and bending the lower ends of the first and second aluminum-plastic tubes, the method for salvaging foreign objects in a nuclear power plant container further comprises: if the foreign object salvage main guide rod is assembled from multiple guide rods, inserting a connector of the guide rod into one end of the pipe opening of another guide rod, aligning the connecting holes, and inserting a quick-lock pin to ensure a secure connection. This operation is repeated until the foreign object salvage main guide rod reaches the target length.

[0009] The beneficial effects of the technical scheme of the present application are that: by fixing two aluminum plastic pipes (i.e. the first aluminum plastic pipe and the second aluminum plastic pipe) side by side on the foreign object fishing main guide rod and setting the lower end of the two aluminum plastic pipes to be bent, the endoscope and the four-corner grabber are guided to the vicinity of the foreign object through the two aluminum plastic pipes respectively, thereby achieving the technical effect of guiding the endoscope and the grabbing tool, which is beneficial to accurately grabbing the foreign object. In addition, by fixing one end of the first nylon rope at the bottom of the foreign object fishing main guide rod and pushing the first nylon rope with a push rod, the first nylon rope is used for traction and position adjustment, thereby achieving the technical effect of moving the tool from the lateral position to the center position of the container and adjusting the position. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 Fig. 1 shows a schematic diagram of the position of a foreign object in a nuclear power plant pressure vessel according to an embodiment of the present application.

[0011] Figure 2 Fig. 2 shows a structure diagram corresponding to the fishing of a foreign object by a nuclear power plant container foreign object fishing device according to an embodiment of the present application.

[0012] Figure 3 Fig. 3 shows a flowchart of a nuclear power plant container foreign object fishing method according to an embodiment of the present application.

[0013] Figure 4 Fig. 4 shows a flowchart of a nuclear power plant container foreign object fishing method according to another embodiment of the present application. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0015] For example, referring to Figure 1 , the nuclear power plant pressure vessel includes a lower support plate 1a, an electric heating element 1b, and a fluctuation tube nozzle 1c. It is assumed below that a foreign object A falls at Figure 1 the position shown, and a nuclear power plant container foreign object fishing device is used to fish the foreign object in the pressure vessel.

[0016] At least one embodiment of the present application provides a nuclear power plant container foreign object fishing device, referring to Figure 2The nuclear power plant container internal foreign object fishing device comprises a foreign object fishing main guide rod 1, a first aluminum plastic pipe 2, a second aluminum plastic pipe 3, a first nylon rope 4, a push rod 5, a second nylon rope 6, a foreign object cage 7, a third nylon rope 8, a camera 9, a endoscope 10 and a four-corner grabber 11. The first aluminum plastic pipe 2 is fixed on the foreign object fishing main guide rod 1, and the first aluminum plastic pipe 2 is used as an endoscope guide pipe. The lower end of the first aluminum plastic pipe 2 is bent to ensure the normal passing of the endoscope. The second aluminum plastic pipe 3 is fixedly connected with the first aluminum plastic pipe 2 and is fixed in parallel on the foreign object fishing main guide rod 1. The lower end of the second aluminum plastic pipe 3 is bent to ensure the normal passing of the four-corner grabber 11. One end of the first nylon rope 4 is fixed at the bottom of the foreign object fishing main guide rod 1. The push rod 5 is used to pull part of the first nylon rope 4 to reach the vertical position of the container center. The second nylon rope 6 is used to pull the foreign object cage 7. The third nylon rope 8 is used to pull and adjust the position of the camera 9. The camera 9 is used to provide illumination and monitoring in the container. The endoscope 10 is used to provide illumination and monitoring at the bottom of the container.

[0017] It should be noted that the foreign object fishing main guide rod 1 is a long rod tool. The push rod 5 is a nylon rope guide rod that can provide guidance for the first nylon rope 4. The four-corner grabber 11 is a foreign object grabbing tool.

[0018] For example, assuming that the size of the pressure container is as shown in Figure 2 The total length of the first aluminum plastic pipe 2 and the second aluminum plastic pipe 3 can be 11.5 m or 13 m. The length of the first nylon rope 4 can be 15 m, and the first nylon rope 4 can be smoothly moved to the edge of the Φ100 mm hole at the bottom of the pressure container. The length of the four-corner grabber 11 can be 15 m. The push rod 5 is used to pull part of the first nylon rope 4 to reach the vertical position of the stabilizer center.

[0019] According to the technical scheme provided in the embodiments of the present application, by fixing two aluminum plastic pipes (i.e., the first aluminum plastic pipe 2 and the second aluminum plastic pipe 3) in parallel on the foreign object fishing main guide rod 1 and bending the lower ends of the two aluminum plastic pipes, the endoscope 10 and the four-corner grabber 11 are guided to the vicinity of the foreign object through the two aluminum plastic pipes, thereby achieving the technical effect of guiding the endoscope and the grabbing tool and being beneficial to accurately grabbing the foreign object. In addition, by fixing one end of the first nylon rope 4 at the bottom of the foreign object fishing main guide rod 1 and pushing the first nylon rope 4 by the push rod 5, the first nylon rope 4 is used for traction and position adjustment, thereby achieving the technical effects of moving the tool from the lateral position to the center position of the container and adjusting the position.

[0020] In at least one embodiment of the present application, the lower ends of the first aluminum plastic pipe 2 and the second aluminum plastic pipe 3 are each bent by 155°. In this way, the normal passing of the endoscope 10 and the four-corner grabber 11 is fully ensured, thereby achieving the technical effect of turning the endoscope 10 and the four-corner grabber 11.

[0021] In at least one embodiment of the present application, the foreign object fishing master guide rod 1 is assembled from multiple guide rods, and pins are used to link between two adjacent guide rods. In this way, the length of the foreign object fishing master guide rod 1 can be adjusted according to the size of the container, and the pins can prevent the risk of falling.

[0022] For example, the foreign object fishing master guide rod 1 is assembled from four guide rods, and the length of each guide rod is 3m.

[0023] In order to complete the foreign object fishing without leaving safety hazards, after several days and nights of hard work, at least one embodiment of the present application also provides a nuclear power plant container internal foreign object fishing method, which only takes 2.5 hours to complete the bottom foreign object fishing, and makes a significant contribution to the 26.94-day work period of the nuclear power plant overhaul. The nuclear power plant container internal foreign object fishing method is effective for fishing deeper foreign objects inside the nuclear power equipment.

[0024] Reference Figure 3 The nuclear power plant container internal foreign object fishing method includes the following steps.

[0025] S1: Open the stabilizer manhole, install the stabilizer flange plate and guide rail.

[0026] S2: Tie the third nylon rope in the nuclear power plant container internal foreign object fishing device of the embodiment of the present application to the camera.

[0027] S3: Connect the camera system and the endoscopy system, and turn on the built-in lamp and the monitoring picture after power on.

[0028] The camera system can be a closed circuit television (CCTV) camera system.

[0029] S4: Send the camera to the center axis inside the stabilizer through the guide rail.

[0030] S5: Adjust the camera pitch angle vertically downward, and send the camera to a position about 300mm above the center hole of the lower support plate of the electric heating element through the third nylon rope.

[0031] S6: Adjust the rotation and pitch of the camera 9, adjust the angle of the camera 9, and confirm the position of the foreign object in the stabilizer lower head area below the lower support plate of the electric heating element.

[0032] When adjusting the rotation of the camera 9, the rotation angle does not exceed 180° clockwise and counterclockwise.

[0033] S7: Monitor the position of the foreign object through the rotation angle of the camera 9 and the endoscopy monitoring picture.

[0034] In at least one embodiment of the present application, reference Figure 4Before step S9, the nuclear power plant container foreign matter fishing method comprises S8.

[0035] S8: If the foreign matter fishing main guide rod 1 is assembled by multiple guide rods, the connecting head of the guide rod is inserted into the pipe mouth end of another guide rod, the connecting holes are aligned, the quick lock pin is inserted, and the connection is determined to be firm. The operation is repeated until the foreign matter fishing main guide rod 1 reaches the target length.

[0036] S9: The first aluminum plastic pipe 2 and the second aluminum plastic pipe 3 are fixed side by side at the end of the foreign matter fishing main guide rod 1, and the lower ends of the first aluminum plastic pipe 2 and the second aluminum plastic pipe 3 are bent.

[0037] For example, two aluminum plastic pipes are fixed side by side on the foreign matter fishing main guide rod 1 during the process of connecting the foreign matter fishing main guide rod 1.

[0038] S10: The first nylon rope 4 is fixed at the bottom end of the foreign matter fishing main guide rod 1.

[0039] S11: The endoscope 10 and the four-corner grabber 11 are guided to the vicinity of the foreign matter through the first aluminum plastic pipe 2 and the second aluminum plastic pipe 3.

[0040] S12: The first nylon rope 4 at the end of the foreign matter fishing main guide rod 1 is hung on the fixing point or the operator's hand, and is sent into the interior through the pressure stabilizer hole. After slowly descending to the center hole of the lower support plate below the electric heating element, the foreign matter fishing main guide rod 1 is controlled to make the four-corner grabber enter the lower part of the lower support plate.

[0041] S13: The foreign matter hanging cage 7 is placed at the bottom of the pressure stabilizer by the second nylon rope 6.

[0042] S14: Under the monitoring positioning of the endoscope 10 monitoring picture, the foreign matter is grabbed by using the four-corner grabber 11.

[0043] S15: After grabbing the foreign matter, the foreign matter fishing main guide rod 1 is slowly pulled out, and the foreign matter is placed in the foreign matter hanging cage 7.

[0044] S16: The foreign matter hanging cage 7 is slowly pulled out, the foreign matter is taken out of the pressure stabilizer, and the foreign matter is placed in the high-level container prepared in advance.

[0045] It should be noted that the combination manner of each technical feature in the embodiments of the present application is not limited to the combination manner described in the embodiments of the present application or the combination manner described in the specific embodiments. All technical features described in the present application can be freely combined or combined in any manner, unless contradictory.

[0046] As used in this application and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. The terms "includes" and "including" should not be construed as exhaustive or exclusive.

[0047] The terms "first," "second," and the like, do not imply either dimensions or importance, but are used merely as identifiers, and are generally intended to distinguish between two independent subjects.

[0048] The preferred embodiments of the application are described above with the understanding that these are the presently preferred embodiments, and are not meant to limit the application in any way.

Claims

1. A method for salvaging foreign matter in a nuclear power plant container, characterized in that: The salvage device for foreign objects in a nuclear power plant container is used for the operation. The salvage device for foreign objects in a nuclear power plant container includes a main guide rod for foreign object salvage, a first aluminum-plastic tube, a second aluminum-plastic tube, a first nylon rope, a push rod, a second nylon rope, a foreign object hanging cage, a third nylon rope, a camera, an endoscope and four-corner grabbers. The first aluminum-plastic tube is fixed to the main guide rod for foreign object salvage, and the first aluminum-plastic tube is used as a guide tube for the endoscope. The lower end of the first aluminum-plastic tube is bent to ensure the normal passage of the endoscope; the second aluminum-plastic tube is fixedly connected to the first aluminum-plastic tube and fixed in parallel to the main guide rod for foreign object salvage, and the lower end of the second aluminum-plastic tube is bent to ensure the normal passage of the four-corner grabbers; one end of the first nylon rope is fixed to the bottom of the main guide rod for foreign object salvage; the push rod is used to pull the middle part of the first nylon rope to the vertical position of the center of the container; the second nylon rope is used to pull the foreign object hanging cage; the third nylon rope is used to pull and adjust the position of the camera; the camera is used to provide lighting and monitoring inside the container; The endoscope is used to provide lighting and monitoring of the bottom of the container. The method for salvaging foreign matter in a nuclear power plant container includes: Open the manhole of the voltage stabilizer and install the voltage stabilizer flange and guide rail; tying the third nylon rope of the foreign body salvaging device in the nuclear power plant container to the camera; Connect the camera system and endoscope inspection system, turn on the built-in light tube and monitor the screen after power on; Send the camera to the center axis inside the stabilizer through the guide rail; Adjust the camera's pitch angle to point vertically downward, and use the third nylon rope to move the camera to a position 300mm above the center hole of the support plate under the electric heating element; Adjust the camera's rotation, pitch, and angle to confirm the location of foreign matter in the area below the voltage stabilizer's lower head, below the lower support plate of the electric heating element; The position of foreign matter is fully monitored through the camera's rotation angle and the endoscope monitoring screen; Fix the first aluminum-plastic tube and the second aluminum-plastic tube side by side at the end of the foreign body salvage main guide rod, and bend the lower ends of the first aluminum-plastic tube and the second aluminum-plastic tube; Fix the first nylon rope to the bottom end of the foreign body salvage main guide rod; Guide the endoscope and the four-corner grippers through the first aluminum-plastic tube and the second aluminum-plastic tube to the vicinity of the foreign body; Tie the first nylon rope at the end of the foreign body salvage main guide rod to a fixed point or the operator's hand, insert it into the interior through the manhole of the voltage stabilizer, and slowly lower it to the center hole of the lower support plate of the electric heating element. Then control the foreign body salvage main guide rod to make the four-corner grabber enter the lower area of ​​the lower support plate; Use the second nylon rope to place the foreign matter cage into the bottom of the stabilizer; Under the monitoring and positioning of the endoscope monitoring screen, use the four-corner gripper to grab the foreign body; After grabbing the foreign object, slowly lift the foreign object salvage guide rod and place the foreign object into the foreign object cage; Slowly lift the foreign body cage, take the foreign body out of the stabilizer, and place the foreign body in a high-pressure container prepared in advance.

2. The method for salvaging foreign matter in a nuclear power plant container according to claim 1, characterized in that: Before fixing the first aluminum-plastic tube and the second aluminum-plastic tube in parallel at the end of the foreign body salvage main guide rod and bending the lower ends of the first aluminum-plastic tube and the second aluminum-plastic tube, the method further includes: If the main guide rod for foreign body salvage is assembled by multiple guide rods, insert the connector of the guide rod into one end of the pipe mouth of the other guide rod, align the connecting holes, insert the quick-lock pin, and make sure the connection is firm. Repeat this operation until the main guide rod for foreign body salvage reaches the target length.

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