Device for detecting inner fillet of connecting pipe of reactor pressure vessel of nuclear power plant

Abstract

The invention provides a nuclear power plant reactor pressure vessel connecting pipe inner fillet detection device which comprises a connecting pipe, a driving part, a universal adjusting probe frame and a connecting fork, the front end of the connecting pipe and the connecting fork are connected to form a Y-shaped symmetrical structure, the driving part is installed on the outer side of the connecting fork, and the universal adjusting probe frame is installed on the driving part. The driving piece is connected with the universal adjusting probe frame to drive the universal adjusting probe frame to be attached to the inner fillet area of the connecting pipe. The device for detecting the inner fillet of the connecting pipe of the reactor pressure vessel of the nuclear power plant, provided by the invention, is better suitable for ultrasonic nondestructive detection of the inner fillet of the connecting pipe of the pressure vessel, and the accuracy and the reliability of detection are improved.

Description

Technical Field

[0001] The invention relates to the technical field of nondestructive testing of a reactor pressure vessel nozzle, and in particular to a device for detecting the inner fillet of a reactor pressure vessel nozzle of a nuclear power plant. Background Art

[0002] The connection between the internal pipe and the pressure vessel cylinder of the nuclear power plant reactor pressure vessel is made of rounded corners. Because this area is in a state of high temperature and pressure for a long time, and a highly radioactive cooling medium flows through it, if there is a leak in this area, a serious safety accident will occur, so the fillet of the pipe must be checked regularly. It is a common and important means to use automated equipment to perform ultrasonic inspections on these areas. In the process of automatic ultrasonic inspection, the tightness of the probe and the surface to be inspected directly affects the signal stability of the ultrasonic inspection. Therefore, there must be an inspection device that can keep the probe in contact with the surface to be inspected during the scanning and inspection process.

[0003] To complete the ultrasonic inspection of the fillet of the reactor pressure vessel nozzle, the ultrasonic probe needs to fit with the fillet area of ​​the nozzle and rotate around the axis of the nozzle during the scanning process. In order for the inspection device to obtain a stable ultrasonic signal during the scanning process, the ultrasonic probe fits with the fillet area of ​​the nozzle and keeps the fillet of the nozzle in a tight fit during the rotation around the axis of the nozzle. Since the fillet of the nozzle of the pressure vessel is a spatial curved surface, it is necessary to adapt to the tight fit state of different inspection areas. Therefore, an inner fillet ultrasonic device must be designed to ensure that the ultrasonic probe is always in tight fit with the fillet of the nozzle to achieve ultrasonic inspection. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects described in the prior art, thereby providing a device for detecting the inner fillet of a nozzle of a pressure vessel of a nuclear power plant reactor, which is better adapted to ultrasonic non-destructive testing of the inner fillet of the nozzle of the pressure vessel, thereby improving the accuracy and reliability of the detection.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A device for detecting the inner fillet of a pipe of a reactor pressure vessel of a nuclear power plant comprises a connecting pipe, a driving member, a universal adjustment probe frame and a connecting fork. The front end of the connecting pipe is connected to the connecting fork to form a Y-shaped symmetrical structure. The driving member is installed on the outer side of the connecting fork. The driving member is connected to the universal adjustment probe frame to drive the universal adjustment probe frame to fit the inner fillet area of ​​the pipe.

[0007] As an practicable manner, the driving member is a driving cylinder, and the driving cylinder is installed on the inclined surface of the connecting fork.

[0008] As an implementable manner, the driving member is a constant force spring driving mechanism, which includes a constant force spring, a spring seat, a guide rail and a guide rail connecting member. The constant force spring is arranged in the spring seat, and the guide rail passes through the spring seat. One end of the guide rail is connected to the constant force spring, and the other end is connected to the guide rail connecting member.

[0009] As an implementable manner, the universally adjustable probe frame includes a probe frame fork, an outer frame and an inner frame which are hinged in sequence from the outside to the inside, and an arc-shaped probe frame is arranged inside the inner frame.

[0010] As an implementable manner, the left and right sides of the inner frame are hinged to the outer frame via a first rotating pin, and the upper and lower sides of the outer frame are hinged to the probe frame fork via a second rotating pin.

[0011] As an implementable manner, two limit screws symmetrically arranged about the second rotation pin are provided on the upper side of the outer frame to limit the angular range of rotation of the outer frame around the second rotation pin.

[0012] As an implementable manner, the inner frame and the arc-shaped probe frame are fixed by screw connection.

[0013] As an implementable manner, the inner frame is a square structure.

[0014] As an implementable manner, the size of the arc angle of the arc probe frame is the same as the size of the inner fillet of the connecting pipe, so as to ensure that the arc probe frame is completely fitted with the inner fillet area of ​​the connecting pipe.

[0015] As an implementable manner, the arc-shaped probe frame is made of polyoxymethylene resin or nylon.

[0016] Compared with the prior art, the device for detecting the inner fillet of a nozzle of a reactor pressure vessel of a nuclear power plant provided by the present invention has the following beneficial effects:

[0017] The probe universal adjustment adaptive fitting technology based on the spatial surface characteristics of the inner fillet of the pipe can realize the adaptive fitting of the ultrasonic probe on the inspection device with the R angle shape characteristics of the spatial surface of the inner fillet of the pipe.

[0018] The probe drive adaptive drive mechanism based on cylinder extension (or constant force spring drive mechanism) realizes adaptive fitting of the space curved surface drop of the inner fillet of the pipe, ensuring the fitting effect of the ultrasonic probe during circumferential rotation scanning.

[0019] The probe frame is arranged in a symmetrical angle based on the approximate positive pressure requirement of the ultrasonic probe and the inner fillet of the pipe. It ensures that the force exerted by the inspection device on the probe during the scanning of the pipe axis is close to the normal line of the inspected fitting surface, ensuring the effectiveness of the action transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a structural diagram of the fillet of a nozzle of a nuclear reactor pressure vessel in the prior art;

[0022] Figure 2 A three-dimensional diagram of a pressure vessel pipe fillet inspection device provided by an embodiment of the present invention, wherein a cylinder drive structure is arranged;

[0023] Figure 3 for Figure 2 A front view of

[0024] Figure 4 A three-dimensional diagram of a pressure vessel pipe fillet inspection device provided by an embodiment of the present invention, wherein a constant force spring drive structure is arranged;

[0025] Figure 5 for Figure 4 A front view of

[0026] Figure 6 A schematic diagram of the structure of a universal adjustable probe frame provided in an embodiment of the present invention;

[0027] Figure 7 A front view of a universal adjustable probe frame provided by an embodiment of the present invention;

[0028] Figure 8 A side view of a universal adjustable probe frame provided by an embodiment of the present invention;

[0029] Fig. 9 A top view of a universal adjustable probe frame provided in an embodiment of the present invention;

[0030] Fig.10 A schematic diagram of an inspection tool for the inner fillet of a nuclear reactor pressure vessel nozzle provided by an embodiment of the present invention.

[0031] Description of reference numerals:

[0032] 1. Pressure vessel connecting pipe; 2. Inner fillet area; 3. Connecting pipe; 4. Driving cylinder; 5. Universal adjustment probe frame; 6. Connecting fork; 7. Probe frame fork; 8. Outer frame; 9. First rotating pin; 10. Inner frame; 11. Arc-shaped probe frame; 12. Limit screw; 13. Second rotating pin; 14. Constant force spring; 15. Spring seat; 16. Guide rail; 17. Guide rail connector; 18. Connecting pipe inner fillet inspection tool. DETAILED DESCRIPTION

[0033] Although the nuclear power plant reactor pressure vessel nozzle fillet detection device of the present invention can be implemented in a variety of different ways, this article will describe the exemplary embodiment in detail in conjunction with the drawings. It is understood that the description herein should be considered as an example of the structure of the nuclear power plant reactor pressure vessel nozzle fillet detection device, and is not intended to limit the protection scope of the present invention to the exemplary embodiment. Therefore, in essence, the drawings and the description of the specific embodiments should be considered to be used to illustrate rather than limit the present invention.

[0034] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "front", "back", "inner", "outer", "horizontal", "vertical" and the like used herein to indicate positions or positional relationships are based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0035] The following is further explained in detail through specific implementation methods.

[0036] In order to facilitate understanding, we first briefly introduce the fillet of the nuclear reactor pressure vessel nozzle. Figure 1 As shown, the fillet area 2 of the pressure vessel nozzle 1 is a fillet with an arc transition, which is the R angle shape of the inner fillet space surface of the nozzle. In order to perform ultrasonic non-destructive testing on the inner fillet of the nozzle of the nuclear reactor pressure vessel of a nuclear power plant and other similar structural surfaces, it is necessary to develop an inspection device so that the ultrasonic probe fits with the inner fillet area of ​​the nozzle and keeps the inner fillet of the nozzle in a fit and tight state during the rotation movement around the axis of the nozzle. In order to better adapt to the ultrasonic non-destructive testing of the inner fillet of the pressure vessel nozzle and improve the accuracy and reliability of the detection, the present invention provides a detection device for the inner fillet of the nozzle of the reactor pressure vessel of a nuclear power plant.

[0037] like Figures 2 to 9As shown, the device for detecting the inner fillet of the pipe of the reactor pressure vessel of the nuclear power plant provided by the present invention is composed of a connecting pipe 3, a driving member, a universal adjustment probe frame 5, and a connecting fork 6. The connecting pipe 3 on the device for detecting the inner fillet of the pipe is connected to the telescopic component and the rotating component at the rear end, and the telescopic component and the rotating component at the rear end drive the entire device for detecting the inner fillet of the pipe to move along the axis of the pipe and rotate around the axis of the pipe. The connecting pipe 3 is connected to the connecting fork 6 by screws. The connecting fork 6 adopts a Y-shaped symmetrical structure. The two inclined surfaces of the connecting fork form a certain angle. The angle is adjusted according to the different diameters of the pipes of the pressure vessel. At present, the angle is 90° (but not limited to 90°). The two inclined surfaces of the connecting fork 6 are respectively installed with driving members.

[0038] As an implementable approach, Figure 2 and Figure 3 As shown, the driving member is a driving cylinder 4 (telescopic cylinder). The front ends of the two driving cylinders 4 are respectively installed with universal adjustment probe frames 5, and the driving cylinders 4 drive the universal adjustment probe frames 5 to fit the fillet area of ​​the pipe. Figure 3 The angle a shown is adjusted accordingly according to the pipe diameter.

[0039] When the inspection device is driven by a driving cylinder, the driving cylinder 4 is in a retracted state, the inspection device rotates to a horizontal state, and the inspection device is driven to align with the center of the connecting pipe 2 through the telescopic part and the rotating part at the rear end, and moves to the vicinity of the connecting pipe 1. The cylinder 4 is extended through the action, and the probe on the universal adjustment probe frame 4 is driven to fit with the inner fillet area 1 of the connecting pipe. The rotating part at the rear end rotates, driving the inspection device to perform ultrasonic scanning of the inner fillet around the axis of the connecting pipe.

[0040] As another possible implementation method, Figure 4 and Figure 5 As shown, the driving member is a constant force spring driving mechanism, and the constant force spring driving mechanism is connected to the connecting fork 6 and the universal adjustment probe frame 5. The constant force spring driving mechanism is composed of a constant force spring 14, a spring seat 15, a guide rail 16, and a guide rail connector 17. The spring seat 15 is connected to the connecting fork 6, and the constant force spring 14 body is placed in the spring seat 15. The guide rail 16 passes through the spring seat 15. One end of the constant force spring 14 is screwed to the guide rail 16, and the other end of the guide rail 16 is connected to the guide rail connector 17. The guide rail connector 17 is connected to the universal adjustment probe frame 5. In the initial state, the constant force spring 14 is not stretched, and the guide rail 16 is in a fully extended state. When the ultrasonic probe on the universal adjustment probe frame 5 is pressed against the inner fillet area of ​​the pipe, the constant force spring 16 is in a stretched state, the guide rail 17 moves toward the rear end of the inspection device, and the guide rail 16 is in a retracted state.

[0041] When the inspection device is driven by a constant force spring drive mechanism, the inspection device rotates to a horizontal state, the constant force spring is in a retracted state, the universal adjustment probe frame is in a fully extended state, and the inspection device drives the inspection device to align with the center of the pipe 2 and move to the vicinity of the pipe 1 opening through the telescopic component and the rotating component at the rear end. The rear end telescopic component continues to drive the inspection device to move along the axis of the pipe toward the pipe 1 opening, driving the probe on the universal adjustment probe frame 5 to fit with the inner fillet area 1 of the pipe until the front end probe is approximately in a fully compressed state, the rear end telescopic component stops moving, and the rear end rotating component rotates, driving the inspection device to perform ultrasonic scanning of the inner fillet around the axis of the pipe. Fig.10 As shown, the nozzle fillet inspection tool 18 performs inspection on the fillet area of ​​the pressure vessel nozzle 1 .

[0042] like Figures 6 to 9 As shown, the universal adjustment probe frame 5 is composed of a probe frame fork 7, an outer frame 8, a first rotating pin 9, an inner frame 10, an arc probe frame 11, a limit screw 12, and a second rotating pin 13. The arc probe frame 11 is made of soft material (such as polyoxymethylene resin or nylon, etc.), and the arc angle of the arc probe frame 11 is the same as the R angle of the inner fillet of the pipe to ensure that the arc probe frame 11 is completely fitted with the inner fillet area of ​​the pipe. A square inner frame 10 is provided on the outer side of the arc probe frame 11, and the inner frame 10 is fixed to the arc probe frame 11 by screws. An outer frame 8 is arranged on the outer side of the inner frame 10, and the outer frame 8 is connected to the inner frame 10 by the first rotating pins 9 arranged on both sides. The inner frame 10 can rotate around the first rotating pins 9 in the outer frame 8 at a certain angle. On the other side of the outer frame 8 where the first rotating pin 9 is arranged, there is a probe frame fork 7. The probe frame fork 7 is connected to the outer frame 8 by two symmetrically arranged second rotating pins 13. The outer frame 8 can rotate around the second rotating pin 13. Limiting screws 12 are installed on both sides of the second rotating pin 13 installed on the outer frame 8 to limit the angle range of rotation of the outer frame 8 around the second rotating pin 13. Through this structure, the arc-shaped probe frame 11 can rotate around two axes, thereby realizing the universal adjustment adaptive function.

[0043] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A device for detecting the inner fillet of a pipe of a nuclear power plant reactor pressure vessel, characterized in that: The invention comprises a connecting tube (3), a driving member, a universally adjustable probe frame (5) and a connecting fork (6), wherein the front end of the connecting tube (3) is connected to the connecting fork (6) to form a Y-shaped symmetrical structure, the driving member is installed on the outer side of the connecting fork (6), and the driving member is connected to the universally adjustable probe frame (5) to drive the universally adjustable probe frame (5) to fit the inner fillet area of ​​the connecting tube.

2. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 1, characterized in that: The driving member is a driving cylinder (4), and the driving cylinder (4) is installed on the inclined surface of the connecting fork (6).

3. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 1, characterized in that: The driving member is a constant force spring driving mechanism, which comprises a constant force spring (14), a spring seat (15), a guide rail (16) and a guide rail connecting member (17); the constant force spring (14) is arranged in the spring seat (15); the guide rail (16) passes through the spring seat (15); one end of the guide rail (16) is connected to the constant force spring (14), and the other end is connected to the guide rail connecting member (17).

4. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 1, characterized in that: The universally adjustable probe frame (5) comprises a probe frame fork (7), an outer frame (8) and an inner frame (10) which are hinged in sequence from the outside to the inside, and an arc-shaped probe frame (11) is arranged inside the inner frame (10).

5. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 4, characterized in that: The left and right sides of the inner frame (10) are hinged to the outer frame (8) via a first rotating pin (9), and the upper and lower sides of the outer frame (8) are hinged to the probe frame fork (7) via a second rotating pin (13).

6. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 5, characterized in that: Two limit screws (12) symmetrically arranged about the second rotating pin (13) are arranged on the upper side of the outer frame (8) to limit the angular range of rotation of the outer frame (8) around the second rotating pin (13).

7. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 4, characterized in that: The inner frame (10) and the arc-shaped probe frame (11) are connected and fixed by screws.

8. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 4, characterized in that: The inner frame (10) is a square structure.

9. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 4, characterized in that: The size of the arc angle of the arc-shaped probe frame (11) is the same as the size of the inner fillet of the pipe, so as to ensure that the arc-shaped probe frame (11) is completely fitted with the inner fillet of the pipe.

10. The device for detecting inner fillet of a pipe joint of a reactor pressure vessel of a nuclear power plant according to claim 4, characterized in that: The material of the arc-shaped probe frame (11) is polyoxymethylene resin or nylon.

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