A CRDM pipe socket in-service crack monitoring device

Abstract

This utility model discloses an in-service crack monitoring device for CRDM tube sockets, belonging to the field of CRDM tube socket technology. Its key technical features include a top cover, a base welded to the top of the top cover, a fixing ring welded to the top of the top cover, a rotating ring rotatably connected to the top of the outer circumference of the fixing ring, and a mounting base fixed to the top of the rotating ring by bolts. An ultrasonic probe is provided on one side of the mounting base, and a power assembly for driving the ultrasonic probe to reciprocate. This utility model utilizes the ultrasonic probe, rotating once clockwise and once counterclockwise, performing two detections to greatly avoid detection blind spots and prevent the ultrasonic probe's wiring from tangling. Regular inspection of the weld between the base and the top cover achieves weld point monitoring, thereby reducing the probability of radioactive material release and improving the safety of the reactor vessel.

Description

Technical Field

[0001] This utility model belongs to the field of CRDM pipe socket technology, specifically relating to an in-service crack monitoring device for CRDM pipe sockets. Background Technology

[0002] As a key component of the top cover of the nuclear reactor pressure vessel, the cracking problem of the CRDM (Control Rod Drive Mechanism) tube seat directly affects the safety and operational reliability of the nuclear power plant.

[0003] A search revealed Chinese patent CN207651185U, which discloses a reactor pressure vessel. By setting a flow-guiding annular cavity assembly and an inner pipe fitting inside the nozzle, the traditional main pipeline structure is eliminated, allowing the pressure vessel to be closely connected to the steam generator and main pump. This reduces the distance between the main equipment and makes the primary coolant system equipment layout more compact. However, during use, if cracks appear at the weld between the CRDM pipe seat and the top cover, they may not be detected in time, leading to coolant leakage, release of radioactive materials, and environmental harm. Utility Model Content

[0004] The purpose of this invention is to provide an in-service crack monitoring device for CRDM pipe sockets to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a CRDM pipe seat in-service crack monitoring device, including a top cover, a seat body welded to the top of the top cover, a fixing ring welded to the top of the top cover, a rotating ring rotatably connected to the top of the outer circumference of the fixing ring, a mounting seat fixed to the top of the rotating ring by bolts, an ultrasonic probe provided on one side of the mounting seat, and a power component for driving the ultrasonic probe to reciprocate.

[0006] As a further embodiment of this utility model, the power assembly includes a fixed frame fixed to the top of the top cover. A motor is fixed to the top outer wall of the fixed frame by bolts. The output shaft of the motor passes through the fixed frame and is connected to a gear by a key. A gear ring is fixed to the outer circumference of the rotating ring by bolts, and the gear ring meshes with the gear. A detection component for inputting signals for forward and reverse rotation of the motor is provided on the top of the fixed frame. A pressing component for locking the rotation of the gear is provided on one side of the fixed frame.

[0007] As a further embodiment of this utility model, the detection component includes a touch switch fixed to one side of the mounting bracket, and a compression frame is fixed to one side of the mounting base by bolts, and the compression frame and the contact of the touch switch can contact each other.

[0008] As a further embodiment of this utility model, the extrusion assembly includes an electric push rod fixed to the outer wall of one side of the fixed frame, and the movable end of the electric push rod passes through the fixed frame and is fixed to a mounting plate by bolts.

[0009] As a further embodiment of this utility model, the top of the mounting base is fixed with a first indicator light and a second indicator light by bolts, and the first indicator light and the second indicator light do not light up at the same time.

[0010] As a further embodiment of this invention, the ultrasonic probe is oriented towards the welded joint between the base and the top cover.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] 1. This utility model uses an ultrasonic probe that rotates one revolution clockwise and one revolution counterclockwise for two detections, which can greatly avoid detection blind spots and prevent the ultrasonic probe's wiring harness from getting tangled. It also allows for regular inspection of the weld between the base and the top cover, achieving the purpose of weld point monitoring, thereby reducing the probability of radioactive material release and improving the safety of the reactor vessel.

[0013] 2. This utility model incorporates a power component, in which a motor drives a gear and a gear ring to rotate, thereby moving the ultrasonic probe. The gear driving the gear ring to rotate is a deceleration motion, which causes the ultrasonic probe to move slowly, avoiding the ultrasonic probe moving too fast and failing to detect cracks, thus improving the accuracy of ultrasonic probe detection.

[0014] 3. This utility model, by providing a detection component, allows the squeezing frame to contact the contact point of the touch switch and squeeze the contact point of the touch switch, thereby emitting an electrical signal to achieve precise control of the ultrasonic probe's rotation of one revolution, thus improving the accuracy of the ultrasonic probe's rotation count. Attached Figure Description

[0015] Figure 1 This is a perspective view of the present utility model;

[0016] Figure 2 This is a partially enlarged view of the present invention;

[0017] Figure 3 This is a partial sectional view of the present invention.

[0018] In the diagram: 1. Top cover; 2. Base; 3. Fixing ring; 4. Gear ring; 5. Fixing frame; 6. Motor; 7. Gear; 8. Touch switch; 9. Extrusion frame; 10. First indicator light; 11. Second indicator light; 12. Mounting base; 13. Ultrasonic probe; 14. Rotating ring; 15. Electric push rod; 16. Mounting plate; 17. Rubber pad. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Please see Figures 1-3 This utility model provides an in-service crack monitoring device for CRDM pipe seats, including a top cover 1, a seat body 2 welded to the top of the top cover 1, a fixing ring 3 welded to the top of the top cover 1, a rotating ring 14 rotatably connected to the top of the outer circumference of the fixing ring 3, a mounting seat 12 fixed to the top of the rotating ring 14 by bolts, an ultrasonic probe 13 is provided on one side of the mounting seat 12, the ultrasonic probe 13 is an air-coupled ultrasonic probe, specifically model JPR-600C, the ultrasonic probe 13 faces the welding point between the seat body 2 and the top cover 1, and a power component is provided on the top of the top cover 1 to drive the ultrasonic probe 13 to reciprocate.

[0021] In use, a high-voltage pulse is applied to the ultrasonic probe 13, causing the core piezoelectric crystal to vibrate mechanically due to the inverse piezoelectric effect. This converts electrical energy into ultrasonic waves, using air as a medium and signal processing technology to achieve non-contact, high-precision detection, thereby detecting cracks. The power assembly drives the rotating ring 14 to rotate once, which in turn drives the ultrasonic probe 13 to rotate once, thus detecting the weld between the base 2 and the top cover 1. The power assembly then drives the ultrasonic probe 13 to rotate in reverse once to prevent the ultrasonic probe 13's wiring from becoming entangled. The two detections greatly reduce the detection blind zone. Regularly detecting the weld between the base 2 and the top cover 1 achieves the purpose of weld point monitoring, thereby reducing the probability of radioactive material release and improving the safety of the reactor vessel.

[0022] In this utility model, the power assembly includes a fixed frame 5 fixed to the top of the top cover 1. A motor 6 is fixed to the top outer wall of the fixed frame 5 by bolts. The output shaft of the motor 6 passes through the fixed frame 5 and is keyed to a gear 7. A gear ring 4 is fixed to the circumferential outer wall of the rotating ring 14 by bolts, and the gear ring 4 meshes with the gear 7. A detection component for inputting signals for forward and reverse rotation of the motor 6 is provided on the top of the fixed frame 5. A pressing component for locking the rotation of the gear 7 is provided on one side of the fixed frame 5.

[0023] When motor 6 is started, it drives gear 7 to rotate, which in turn drives gear ring 4 to rotate, which in turn drives rotating ring 14 to rotate, thus moving ultrasonic probe 13. The rotation of gear ring 4 by gear 7 is a decelerating motion, which makes ultrasonic probe 13 move slowly, avoiding the ultrasonic probe 13 moving too fast and failing to detect cracks, thereby improving the accuracy of ultrasonic probe 13 detection. After motor 6 rotates one revolution, the detection component will detect that motor 6 has rotated one revolution, causing motor 6 to reverse one revolution. When motor 6 is powered off, gear 7 may continue to rotate due to inertia. The squeezing component locks gear 7, thereby eliminating the inertia of gear 7 and making the detection results of the detection component more accurate.

[0024] The detection component includes a touch switch 8, model SKRKAEE020, fixed to one side of the mounting bracket 5. A compression frame 9 is fixed to one side of the mounting base 12 by bolts, and the compression frame 9 can contact the contacts of the touch switch 8. During the rotation of the mounting base 12, the mounting base 12 will drive the compression frame 9 to move and rotate, thereby causing the compression frame 9 to disengage from the touch switch 8. After the mounting base 12 rotates one revolution, the compression frame 9 will re-contact the contacts of the touch switch 8 and compress the contacts of the touch switch 8, thereby emitting an electrical signal to achieve precise control of the rotation of the ultrasonic probe 13 one revolution.

[0025] The extrusion assembly includes an electric push rod 15 fixed to the outer wall of one side of the fixed frame 5. The movable end of the electric push rod 15 passes through the fixed frame 5 and is fixed to a mounting plate 16 by bolts. A rubber pad 17 is adhered to one side of the mounting plate 16, and the rubber pad 17 can contact the gear 7. The rubber pad 17 reduces the wear between the mounting plate 16 and the gear 7. When the electric push rod 15 is activated, the electric push rod 15 extends and drives the mounting plate 16 and the rubber pad 17 to move toward the gear 7, thereby making the rubber pad 17 contact with the gear 7 and locking the gear 7, thereby eliminating the rotational inertia of the gear 7, so that the extrusion frame 9 can always be in contact with the touch switch 8, thereby achieving precise control of the rotation of the motor 6.

[0026] The mounting base 12 is fixed to the top with a first indicator light 10 and a second indicator light 11 by bolts. The first indicator light 10 and the second indicator light 11 do not light up at the same time. The first indicator light 10 lights up red and the second indicator light 11 lights up green. When a crack is detected, the first indicator light 10 lights up and when there is no crack, the second indicator light 11 lights up, so that the detection results can be observed in a timely manner.

[0027] It should be noted that the motor 6, touch switch 8, first indicator light 10, second indicator light 11, ultrasonic probe 13 and electric push rod 15 in this utility model are all standard electrical components. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods, and will not be elaborated on here.

[0028] The working principle of this utility model is as follows: When in use, the ultrasonic probe 13 is started, and the motor 6 is started. The motor 6 drives the gear 7 to rotate, which in turn drives the gear ring 4 to rotate, and then drives the rotating ring 14 to rotate, thereby moving the ultrasonic probe 13 and rotating it one revolution. This allows the ultrasonic probe 13 to be detected at the weld between the base 2 and the top cover 1. The motor 6 is then started again to reverse the direction, thereby rotating the ultrasonic probe 13 one revolution in reverse. This avoids the wiring harness of the ultrasonic probe 13 from getting tangled. At the same time, the two detections can greatly avoid blind spots. The weld between the base 2 and the top cover 1 is periodically detected to achieve the purpose of weld point monitoring, thereby reducing the probability of radioactive material release and improving the safety of the reactor vessel.

[0029] Finally, the following points should be noted: In the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection" and "linkage" should be interpreted broadly, and can be mechanical or electrical connection, or internal connection between two components, or direct connection. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may change.

[0030] The electronic components and modules used in this utility model can all be parts that are commonly used in the market and can achieve the specific functions in this case. The specific models and sizes can be selected and adjusted according to actual needs.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A CRDM nozzle in-service crack monitoring device, comprising a top cover (1), a seat body (2) is welded on the top of the top cover (1), characterized in that: A fixing ring (3) is welded to the top of the top cover (1). A rotating ring (14) is rotatably connected to the top of the outer circumference of the fixing ring (3). A mounting base (12) is fixedly connected to the top of the rotating ring (14). An ultrasonic probe (13) is provided on one side of the mounting base (12). A power assembly that drives the ultrasonic probe (13) to reciprocate is provided on the top of the top cover (1).

2. The in-service crack monitoring device for a CRDM socket according to claim 1, characterized in that: The power assembly includes a mounting bracket (5) fixed to the top of the top cover (1). A motor (6) is fixedly connected to the top outer wall of the mounting bracket (5). The output shaft of the motor (6) passes through the mounting bracket (5) and is keyed to a gear (7). A gear ring (4) is fixedly connected to the outer circumference of the rotating ring (14), and the gear ring (4) meshes with the gear (7). A detection component for inputting signals for forward and reverse rotation of the motor (6) is provided on the top of the mounting bracket (5). A pressing component for locking the rotation of the gear (7) is provided on one side of the mounting bracket (5).

3. The in-service crack monitoring device for a CRDM socket according to claim 2, characterized in that: The detection component includes a touch switch (8) fixed on one side of the mounting bracket (5), and a pressing bracket (9) is fixedly connected to one side of the mounting base (12), and the pressing bracket (9) and the contact of the touch switch (8) can contact each other.

4. The in-service crack monitoring device for a CRDM socket according to claim 2, characterized in that: The extrusion assembly includes an electric push rod (15) fixed to the outer wall of one side of the fixed frame (5), and the movable end of the electric push rod (15) passes through the fixed frame (5) and is fixedly connected to a mounting plate (16).

5. The in-service crack monitoring device for a CRDM socket according to claim 1, characterized in that: The top of the mounting base (12) is fixedly connected to a first indicator light (10) and a second indicator light (11), and the first indicator light (10) and the second indicator light (11) do not light up at the same time.

6. The in-service crack monitoring device for a CRDM socket according to claim 1, characterized in that: The ultrasonic probe (13) is oriented toward the weld between the base (2) and the top cover (1).

7. The in-service crack monitoring device for a CRDM socket according to claim 4, characterized in that: A rubber pad (17) is adhered to one side of the mounting plate (16), and the rubber pad (17) can contact the gear (7).

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