Self-adaptive ultrasonic detection device for pressure vessel connecting pipe

Abstract

The invention discloses a self-adaptive ultrasonic detection device for a pressure vessel connecting pipe, the self-adaptive ultrasonic detection device comprises a base connected with a driving mechanism and at least three detection modules, the base is of an arc-shaped structure with the radius smaller than that of a flow guide ring cavity of a pressure vessel, and the three detection modules are arranged on the base at intervals; each detection module comprises a telescopic mechanism, a plurality of self-adaptive probe frames and a plurality of ultrasonic probes, the telescopic mechanisms are fixedly mounted on the base, and the output ends of the telescopic mechanisms are fixedly connected with the self-adaptive probe frames so as to drive the self-adaptive probe frames to do linear motion; the ultrasonic probe is installed on the self-adaptive probe frame, and the self-adaptive probe frame has the self-adaptive pitching function and the self-adaptive side tilting function so that the ultrasonic probe can adapt to the surface contour of a workpiece. Through the arrangement of the arc-shaped base and the multiple detection modules and the cooperative cooperation of telescopic driving and the self-adaption function, a set of integrated linkage detection mechanism is formed, and continuous, stable and full-coverage ultrasonic detection of the circumferential weld in a compact space is achieved.

Description

Technical Field

[0001] This invention relates to the field of in-service inspection technology for nuclear power plants, and more particularly to an adaptive ultrasonic testing device for pressure vessel nozzles. Background Technology

[0002] The nuclear reactor pressure vessel is the most critical and irreplaceable piece of equipment in a nuclear power plant, and its structural integrity directly affects the safe operation of the plant. Therefore, during manufacturing, installation, and service, it is necessary to periodically conduct rigorous non-destructive testing on its critical welds, especially the assembly ring weld between the inlet / outlet nozzles and the vessel body. Automated ultrasonic testing technology has become the mainstream method due to its high testing efficiency, recordable data, and high reliability. Its key component is the probe holder, which carries the ultrasonic probe into the testing area and scans the weld with stable coupling pressure and precise trajectory.

[0003] Existing conventional ultrasonic testing probe mounts for pressure vessels are primarily designed for traditional large pressurized water reactors. These reactors typically have relatively spacious interiors, facilitating probe mount entry and deployment. The design of these probe mounts prioritizes achieving wide coverage and complex movement trajectories, without adequately considering maneuverability and operability in extremely confined spaces.

[0004] However, the pressure vessels of my country's independently developed advanced compact small reactors employ an integrated and modular design, resulting in complex internal structures. A prominent technical challenge lies in the flow-guiding annular cavity structure within the pressure vessel's inner wall. This leads to the following insurmountable difficulties with existing ultrasonic testing probe holders for pressure vessels: 1. The space is extremely narrow. From the pressure vessel inlet to the assembly ring weld area of ​​the nozzle to be inspected, the space is much smaller than the working space required for probe holder inspection due to the presence of the flow guide ring cavity. Existing probe holders are bulky and have a large unfolding radius, making them unable to pass through this narrow channel, or unable to unfold effectively after passing through, resulting in the problem of "being able to get in, but not being able to unfold".

[0005] 2. Severely Restricted Scanning Movement. The guide ring cavity is adjacent to the assembly ring weld, creating a physical obstacle. Conventional probe holders rely on continuous axial movement to complete the scanning of the entire weld ring. However, in this structure, the guide ring cavity obstructs the probe's movement path, preventing the probe from performing continuous axial scanning and creating undetectable "blind spots" in the weld, seriously threatening equipment safety assessment. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide an adaptive ultrasonic testing device for pressure vessel nozzles.

[0007] The technical solution adopted by the present invention to solve its technical problem is: to construct an adaptive ultrasonic testing device for a pressure vessel nozzle, including a base connected to a drive mechanism and at least three testing modules. The base is an arc-shaped structure with a radius smaller than the radius of the flow guide ring cavity of the pressure vessel, and the three testing modules are spaced apart on the base. Each of the detection modules includes a telescopic mechanism, several adaptive probe holders, and several ultrasonic probes. The telescopic mechanism is fixedly installed on the base, and the output end of the telescopic mechanism is fixedly connected to the adaptive probe holder to drive the adaptive probe holder to perform linear motion. The ultrasonic probe is installed on the adaptive probe holder, which has adaptive pitch and adaptive tilt functions to adapt the ultrasonic probe to the surface contour of the workpiece.

[0008] Furthermore, the telescopic mechanism includes a primary telescopic mechanism and several secondary telescopic mechanisms. The output end of the primary telescopic mechanism is connected to the fixing parts of all the secondary telescopic mechanisms to realize the rapid extension and active retraction of the ultrasonic probe. The output end of each secondary telescopic mechanism is connected to an adaptive probe holder to provide a constant contact force between the ultrasonic probe and the external object.

[0009] Furthermore, the primary telescopic mechanism includes a driving component, a fixed body, and a movable plate. The fixed body is fixedly installed on the base. The cylinder of the driving component is fixed to the fixed body, and the output end of the driving component is connected to the movable plate to drive the movable plate to move linearly relative to the fixed body. The movable plate is fixedly connected to the fixing component of the secondary telescopic mechanism to drive the secondary telescopic mechanism to move synchronously.

[0010] Furthermore, the secondary telescopic mechanism includes a constant force component, a movable frame, and a fixing member fixedly connected to the movable plate. The constant force component is mounted on the fixing member, and the output end of the constant force component is connected to the movable frame to provide a constant coupling force to the movable frame. The adaptive probe frame is mounted on the movable frame.

[0011] Furthermore, the constant force assembly includes a constant force spring, a spring mounting base, a guide shaft, and a spring pressure plate. The guide shaft is slidably inserted into the movable plate, and the first end of the guide shaft is fixedly connected to the spring mounting base, while the second end of the guide shaft is fixedly connected to the movable frame. The first end of the constant force spring is fixed to the spring mounting base, and the second end of the constant force spring is connected to the spring pressure plate, which is fixed to the movable plate.

[0012] Furthermore, the adaptive probe holder includes a probe frame and a probe outer frame. The ultrasound probe is mounted on the probe frame, and the probe frame is hinged to the probe outer frame via a first pivot to achieve the adaptive pitch function of the ultrasound probe. The probe outer frame is hinged to the movable frame via a second pivot to achieve the adaptive tilt function of the ultrasound probe.

[0013] Furthermore, the detection module also includes omnidirectional ball bearings, which are disposed on the moving plate to reduce friction during scanning.

[0014] Furthermore, the telescopic mechanism also includes a reset member, which is hinged to the movable plate via a third pivot, and the first end of the reset member is hinged to the movable frame via a fourth pivot. A plunger is provided on the fixed body. When the first-stage telescopic mechanism retracts to the preset position, the second end of the reset member abuts against the plunger and rotates around the third rotating shaft, thereby pressing the first end of the reset member back onto the movable frame, so that the movable frame overcomes the force of the constant force component and moves in the retraction direction.

[0015] Furthermore, the number of detection modules is three, and the three detection modules are distributed circumferentially along the base, with the central angle between two adjacent detection modules being 70°.

[0016] Furthermore, the base has a semi-circular structure.

[0017] By implementing this invention, the following beneficial effects are achieved: The adaptive ultrasonic testing device for pressure vessel nozzles of this invention achieves smooth entry and exit of the testing module in confined spaces such as the flow-guiding annular cavity by setting an arc-shaped base structure with a radius smaller than that of the pressure vessel's flow-guiding annular cavity. By setting at least three testing modules spaced apart on the arc-shaped base, a distributed testing coverage is formed in the circumferential direction, enabling simultaneous multi-point scanning of local areas of the circumferential weld, effectively improving testing efficiency and data integrity. By setting a telescopic mechanism fixedly connected to the base and driving the linear movement of the adaptive probe frame, the ultrasonic probe is precisely fed and retracted radially, achieving controllable deployment and safe retraction of the ultrasonic probe in the working position. By setting an adaptive adjustment function on the adaptive probe frame, it has the ability to dynamically conform to the surface contour of the workpiece, achieving stable acoustic coupling of the ultrasonic probe on complex curved or uneven surfaces, ensuring the reliability and consistency of the detection signal. Through the coordinated operation of the device's arc-shaped base, multi-detection module layout, telescopic drive, and adaptive function, an integrated linkage detection mechanism is formed, enabling continuous, stable, and full-coverage ultrasonic testing of circumferential welds within a compact space. Ultimately, this achieves the goal of efficient, reliable, and non-destructive testing of circumferential welds in pressure vessel nozzles. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of the structure of an adaptive ultrasonic testing device for a pressure vessel nozzle according to an embodiment of the present invention; Figure 2 yes Figure 1 An assembly diagram of the adaptive ultrasonic testing device and its drive mechanism. Figure 3 yes Figure 1 A schematic diagram of the detection module in the diagram; Figure 4 yes Figure 3 A partial structural diagram of the detection module is shown, in which only one ultrasonic probe is shown; Figure 5 yes Figure 3 The top view of the detection module shows the retracted state of the secondary telescopic mechanism. Figure 6 yes Figure 3 The side view of the detection module in the middle shows the retracted state of the secondary telescopic mechanism; Figure 7 yes Figure 3 The top view of the detection module shows the extended state of the secondary telescopic mechanism. Figure 8 yes Figure 3 The side view of the detection module shows the extended state of the secondary telescopic mechanism; Figure 9 yes Figure 2 A schematic diagram illustrating the usage of an adaptive ultrasonic testing device for pressure vessel nozzles. Detailed Implementation

[0019] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] In the description of the invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or a chemical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] See Figures 1 to 9 One embodiment of the present invention discloses an adaptive ultrasonic testing device for pressure vessel nozzles, solving the industry-level problem of achieving stable, efficient, and full-coverage non-destructive testing in extremely narrow and complex confined spaces. It is particularly suitable for the inspection of circumferential welds on nozzles 6 of pressure vessel 4 in compact small modular reactors. It is also applicable to the inspection of circumferential welds on inlet / outlet nozzles, manholes, inspection holes, and other parts of pressure vessel 4 in traditional nuclear power plants, improving the efficiency and reliability of testing in these locally confined spaces and replacing traditional bulky testing fixtures. It can also be extended to the in-service inspection of welds and weld overlays on nozzles 6 of other nuclear-grade vessels such as main pumps, steam generators, and pressurizers in nuclear power plants. The following description uses the inspection of circumferential welds on nozzles 6 of pressure vessel 4 in a compact small modular reactor as an example: like Figure 1 and Figure 2As shown, the adaptive ultrasonic testing device for pressure vessel nozzles includes a base 1 connected to a drive mechanism 3 and at least three testing modules 2. The base 1 is an arc-shaped structure with a radius smaller than the radius of the flow-guiding annular cavity 5 of the pressure vessel 4. The three testing modules 2 are spaced apart on the base 1. The base 1 provides an installation platform and spatial positioning reference for all testing modules 2, and its curvature determines the initial distribution pattern of the probe group. The base 1 can be a major arc, a minor arc, or a semi-circular arc, as long as its maximum radial dimension is smaller than the radius of the flow-guiding annular cavity 5. In some other embodiments, the base 1 can also be a polygonal, approximately arc-shaped frame, with its maximum radial dimension smaller than the radius of the flow-guiding annular cavity 5. Optionally, the base 1 is a semi-circular structure. The number of testing modules 2 is three, and the three testing modules 2 are distributed circumferentially around the base 1, with a central angle of 70° between two adjacent testing modules 2. The central angle between the central axes of the cylinders of any testing module 2 is 70°, using the central axis of the cylinder of any testing module 2 as a reference line.

[0023] The entire adaptive ultrasonic testing device of this invention is connected to the drive mechanism 3 via the base 1. Optionally, the drive mechanism 3 is a robotic arm, as in the prior art, used to move the entire device, generally moving axially along the nozzle 6 and rotating circumferentially along the nozzle 6. The arc-shaped base 1 ensures the passage of the entire device within the flow-guiding annular cavity 5 of the pressure vessel 4 and the nozzle 6. The multi-detection module 2 and the telescopic mechanism enable obstacle-crossing scanning even when obstructed by the flow-guiding annular cavity 5 within the nozzle 6 of the pressure vessel 4.

[0024] Generally, the pressure vessel 4 has two flow-guiding annular cavities 5 located inside. The first flow-guiding annular cavity 5 is located at the opening of the nozzle 6, and the second flow-guiding annular cavity 5 is located inside the nozzle 6. The adaptive ultrasonic testing device of this invention needs to extend from inside the pressure vessel 4 through the flow-guiding annular cavity 5 at the opening of the nozzle 6 to the circumferential weld inside the nozzle 6 for ultrasonic testing. Since the positions of the flow-guiding annular cavity 5 inside the nozzle 6 overlap with the circumferential weld inside the nozzle 6, the adaptive ultrasonic testing device needs to extend into the gap between the flow-guiding annular cavity 5 inside the nozzle 6 and the sidewall of the nozzle 6 to perform ultrasonic testing. The arc-shaped base 1, with a radius smaller than the radius of the flow-guiding annular cavity 5 of the pressure vessel 4, ensures that the testing module 2 can safely pass through the flow-guiding annular cavity 5 at the opening of the nozzle 6 under any conditions.

[0025] like Figure 3As shown, each detection module 2 includes a telescopic mechanism, several adaptive probe holders 23, and several ultrasonic probes 24. The telescopic mechanism is fixedly mounted on the base 1, and its output end is fixedly connected to the adaptive probe holder 23 to drive the adaptive probe holder 23 to perform linear motion. The ultrasonic probes 24 are mounted on the adaptive probe holders 23, which have adaptive pitch and adaptive tilt functions to adapt the ultrasonic probes 24 to the surface contour of the workpiece. Optionally, one adaptive probe holder 23 corresponds to one ultrasonic probe 24, and each detection module 2 can be equipped with two adaptive probe holders 23 and two ultrasonic probes 24. The entire adaptive ultrasonic testing device has six ultrasonic probes 24, enabling ultrasonic scanning from six different angles.

[0026] The telescopic mechanism is fixedly connected to the base 1 and drives the adaptive probe holder 23 to move linearly, enabling the ultrasonic probe 24 to be precisely fed and retracted radially, thus achieving controllable deployment and safe retraction of the ultrasonic probe 24 in the working position. By incorporating adaptive pitch and adaptive tilt functions on the adaptive probe holder 23, it has the ability to dynamically conform to the workpiece surface contour, achieving stable acoustic coupling of the ultrasonic probe 24 on complex curved or uneven surfaces, ensuring the reliability and consistency of the detection signal. Through the coordinated operation of the arc-shaped base 1, the multi-detection module 2 layout, the telescopic drive, and the adaptive function, an integrated linkage detection mechanism is formed, achieving continuous, stable, and full-coverage ultrasonic detection of circumferential welds within a compact space, ultimately achieving efficient, reliable, and non-destructive testing of the circumferential welds in the nozzle 6 of the pressure vessel 4.

[0027] Furthermore, such as Figures 3 to 8In some embodiments, the telescopic mechanism includes a primary telescopic mechanism 21 and several secondary telescopic mechanisms 22. The output end of the primary telescopic mechanism 21 is connected to the fixing member 223 of all the secondary telescopic mechanisms 22 to achieve rapid extension and active retraction of the ultrasonic probe 24. The output end of each secondary telescopic mechanism 22 is connected to an adaptive probe holder 23 to provide a constant contact force between the ultrasonic probe 24 and the external object. The primary telescopic mechanism 21 is used to achieve rapid extension and active retraction of the ultrasonic probe 24, providing the detection module 2 with a large stroke and actively controlled linear motion required from transportation to the working position. After the primary telescopic mechanism 21 delivers the ultrasonic probe 24 to the workpiece surface, the secondary telescopic mechanism 22 uses the pipe 6 to control the pressure of the ultrasonic probe 24, providing a constant contact force independent of displacement, solving the problem of unstable coupling pressure on uneven surfaces, ensuring ultrasonic signal quality, and achieving passive obstacle crossing. When scanning obstacles such as the guide ring cavity 5, the moving frame 222 can be passively compressed or extended to adapt to stroke changes while maintaining constant pressure. The number of secondary telescopic mechanisms 22 corresponds one-to-one with the number of adaptive probe holders 23, meaning the number of secondary telescopic mechanisms 22 is the same as the number of ultrasonic probes 24, with one secondary telescopic mechanism 22 controlling the pressure of one ultrasonic probe 24. In this embodiment, each telescopic mechanism includes two secondary telescopic mechanisms 22, such as... Figure 5 As shown, only the left secondary telescopic mechanism 22 is marked. The right secondary telescopic mechanism 22 is the same as the left secondary telescopic mechanism 22 and is not marked.

[0028] Furthermore, such as Figures 5 to 8 As shown, in some embodiments, the primary telescopic mechanism 21 includes a driving component 211, a fixed body 212, and a movable plate 213. The fixed body 212 is fixedly mounted on the base 1. The cylinder of the driving component 211 is fixed to the fixed body 212, and the output end of the driving component 211 is connected to the movable plate 213 to drive the movable plate 213 to move linearly relative to the fixed body 212. The movable plate 213 is fixedly connected to the fixing component 223 of the secondary telescopic mechanism 22 to drive the secondary telescopic mechanism 22 to move synchronously. The driving component 211 is a cylinder, with its cylinder body fixed to the fixed body 212 and its piston rod connected to the movable plate 213. It is understood that in other embodiments, an electric push rod, a ball screw pair, or a hydraulic cylinder can be used instead of a cylinder to achieve the same function.

[0029] Optionally, such as Figure 5As shown, to enhance rigidity and stability, the primary telescopic mechanism 21 further includes at least two guide posts 215 and a connecting plate 216 that fixes the two guide posts 215 together. The guide posts 215 are arranged parallel to the piston rod of the cylinder, and the end away from the connecting plate 216 is rigidly connected to the moving plate 213, together forming a multi-support kinematic pair. The guide posts 215 pass through linear bearings in the fixed body 212, which can provide guidance for the movement of the cylinder.

[0030] Furthermore, such as Figures 5 to 8 As shown, in some embodiments, the secondary telescopic mechanism 22 includes a constant force component 221, a movable frame 222, and a fixing member 223 fixedly connected to the movable plate 213. The constant force component 221 is mounted on the fixing member 223, and its output end is connected to the movable frame 222 to provide a constant coupling force to the movable frame 222. The adaptive probe frame 23 is mounted on the movable frame 222. Optionally, the fixing member 223 is an L-shaped plate, with its upper part fixedly connected to the movable plate 213 and its bottom connected to the constant force component 221, providing the constant force component 221 with a more inward installation space than the movable plate 213, making the structure more compact. Here, "inner side" refers to the side closer to the interior of the base 1.

[0031] Furthermore, such as Figure 5 and Figure 6 ,or Figure 7 and Figure 8 As shown, in some embodiments, the constant force assembly 221 includes a constant force spring 2211, a spring mounting base 2212, a guide shaft 2213, and a spring pressure plate 2214. The guide shaft 2213 is slidably inserted into the movable plate 213, and its first end is fixedly connected to the spring mounting base 2212, while its second end is fixedly connected to the movable frame 222. The first end of the constant force spring 2211 is fixed to the spring mounting base 2212, and its second end is connected to the spring pressure plate 2214, which is fixed to the movable plate 213. Optionally, there are at least two guide shafts 2213, which may be equipped with linear bearings to prevent the movable frame 222 from rotating and ensure the stability of the ultrasonic probe 24.

[0032] Furthermore, such as Figure 3 and Figure 4As shown, in some embodiments, the adaptive probe holder 23 includes a probe frame 231 and a probe outer frame 232. The ultrasonic probe 24 is mounted on the probe frame 231. The probe frame 231 is hinged to the probe outer frame 232 via a first pivot 233, enabling the ultrasonic probe 24 to have an adaptive pitch function. The probe outer frame 232 is hinged to the movable frame 222 via a second pivot 234, enabling the ultrasonic probe 24 to have an adaptive tilt function. The adaptive probe holder 23 forms a dual-pivot floating structure, allowing the probe to adapt to minute unevenness on the workpiece surface. Based on the constant force clamping of the constant force component 221, the ultrasonic probe 24 is further allowed to move slightly in multiple degrees of freedom to conform to the workpiece surface. This can eliminate problems such as poor coupling or wear of the ultrasonic probe 24 caused by micro-unevenness of the workpiece surface, installation errors, or slight fluctuations in the scanning path.

[0033] Optionally, the axes of the first rotating shaft 233 and the second rotating shaft 234 should be perpendicular to each other, forming a universal joint structure to achieve pitch and yaw in two directions. Miniature dampers or O-rings can be installed at the first rotating shaft 233 and the second rotating shaft 234 to provide weak friction and prevent the ultrasonic probe 24 from wobbling freely in a non-contact state.

[0034] Specifically, the probe frame 231 is hinged to the probe outer frame 232 via a first rotating shaft 233. The ultrasonic probe 24 can pitch within a certain angle range, such as ±15 degrees, around the first rotating shaft 233. This movement is used to adapt to the longitudinal curvature changes of the surface of the workpiece being tested in the direction of movement of the ultrasonic probe 24, ensuring effective contact between the leading and trailing edges of the ultrasonic probe 24. The probe outer frame 232 is hinged to the moving frame 222 via a second rotating shaft 234. The entire adaptive probe frame 23, including the probe frame 231 and the probe outer frame 232, can tilt within a certain angle range, such as ±10 degrees, around the second rotating shaft 234. This movement is used to adapt to the lateral curvature changes of the surface of the workpiece being tested in the direction perpendicular to the probe's movement, ensuring effective contact between the left and right sides of the probe.

[0035] Furthermore, such as Figure 3 As shown, in some embodiments, the detection module 2 further includes a universal ball bearing 25, which is disposed on the moving plate 213 to reduce friction during scanning. During scanning, the detection module 2 contacts the workpiece surface and bears most of the frictional force from lateral movement. This greatly reduces the frictional resistance during the movement of the moving frame 222, allowing even small force changes in the constant force spring 2211 to sensitively maintain the pressure of the ultrasonic probe 24, while also making the scanning motion smoother. Simultaneously, it protects the workpiece surface and the ultrasonic probe 24 from scratches.

[0036] Furthermore, such as Figure 6 and Figure 8As shown, in some embodiments, the telescopic mechanism further includes a reset member 224, which is hinged to the moving plate 213 via a third pivot 225. The first end of the reset member 224 is hinged to the moving frame 222 via a fourth pivot 226. A plunger 214 is provided on the fixed body 212. When the primary telescopic mechanism 21 retracts to a preset position, the second end of the reset member 224 abuts against the plunger 214 and rotates around the third pivot 225, thereby pressing the first end of the reset member 224 back onto the moving frame 222, causing the moving frame 222 to overcome the force of the constant force assembly 221 and move in the retraction direction. When the primary telescopic mechanism 21 retracts, the reset member 224 provides a mechanical forcing means to ensure that the secondary telescopic mechanism 22 can overcome the tension of the constant force spring 2211 and retract the ultrasonic probe 24 into a safe contour.

[0037] like Figures 5 to 9 As shown, the overall workflow of the adaptive ultrasonic testing device of the present invention is as follows: In the entry stage (reference) Figure 5 and Figure 6 Status): The first-level telescopic mechanism 21 retracts, the reset piece 224 forces the second-level telescopic mechanism 22 to retract, all components retract within the envelope of the arc-shaped base 1, and the driving robotic arm sends the entire device through the guide ring cavity 5 into the pipe 6.

[0038] During the unfolding and coupling phase (see reference) Figure 7 and Figure 8 (Status): The first-stage telescopic mechanism 21 extends, pushing the entire detection module 2 forward. After the ultrasonic probe 24 contacts the workpiece (i.e., after the ultrasonic probe 24 contacts the side wall of the connecting pipe 6), the first-stage telescopic mechanism 21 continues to advance, and the constant force spring 2211 of the second-stage telescopic mechanism 22 is stretched, and the constant force begins to build up. The universal ball bearing 25 contacts the side wall surface of the connecting pipe 6. The point at which the constant force spring 2211 of the second-stage telescopic mechanism 22 is stretched can be any position where the first-stage telescopic mechanism 21 extends, not limited to after the ultrasonic probe 24 contacts the side wall of the connecting pipe 6.

[0039] During the sweeping and obstacle-crossing phase (see reference) Figure 9 The drive arm moves the entire device circumferentially along the weld seam. A constant-force spring 2211 ensures constant pressure. An adaptive probe holder 23 adjusts its posture to ensure close contact with the sidewall weld of the connector 6, meaning the contact surfaces of all ultrasonic probes 24 form intermittent arc surfaces or approximate arc surfaces that match the curvature of the sidewall of the connector 6. Universal ball bearings 25 reduce friction. When encountering obstacles, the secondary telescopic mechanism 22 passively extends and retracts to overcome them.

[0040] In the exit phase (see reference) Figure 5 and Figure 6Status): The first-level telescopic mechanism 21 retracts, triggering the reset plate to force the second-level telescopic mechanism 22 to retract, the device returns to its compact form, and the driving robotic arm drives the entire device to safely exit.

[0041] By implementing this invention, the following beneficial effects are achieved: The adaptive ultrasonic testing device for pressure vessel nozzles of the present invention achieves smooth entry and exit of the testing module 2 in confined spaces such as the flow-guiding annular cavity 5 by setting an arc-shaped base 1 with a radius smaller than that of the pressure vessel 4. By setting at least three testing modules 2 spaced apart on the arc-shaped base 1, a distributed testing coverage is formed in the circumferential direction, enabling simultaneous multi-point scanning of local areas of the circumferential weld, effectively improving testing efficiency and data integrity. By setting a telescopic mechanism fixedly connected to the base 1 and driving the adaptive probe holder 23 to move linearly, the ultrasonic probe 24 is precisely fed and retracted radially, achieving controllable deployment and safe retraction of the ultrasonic probe 24 in the working position. By setting an adaptive adjustment function on the adaptive probe holder 23, it has the ability to follow and conform to the surface contour of the workpiece, achieving stable acoustic coupling of the ultrasonic probe 24 on complex curved or uneven surfaces, ensuring the reliability and consistency of the detection signal. Through the coordinated operation of the arc-shaped base 1, the multi-detection module 2 layout, the telescopic drive and adaptive function of this device, an integrated linkage detection mechanism is formed, realizing continuous, stable and full-coverage ultrasonic detection of circumferential welds in a compact space, and ultimately achieving the goal of efficient, reliable and non-destructive testing of circumferential welds in the nozzle 6 of the pressure vessel 4.

[0042] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that for those skilled in the art, the above embodiments or technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention. These all fall within the protection scope of the present invention. That is, the embodiments described "in some embodiments" can be freely combined with any of the embodiments above and below. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. An adaptive ultrasonic testing device for pressure vessel nozzles, characterized in that, It includes a base (1) connected to the drive mechanism (3) and at least three detection modules (2). The base (1) is an arc-shaped structure with a radius smaller than the radius of the flow guide ring cavity (5) of the pressure vessel (4). The three detection modules (2) are spaced apart on the base (1). Each of the detection modules (2) includes a telescopic mechanism, several adaptive probe holders (23) and several ultrasonic probes (24). The telescopic mechanism is fixedly installed on the base (1), and the output end of the telescopic mechanism is fixedly connected to the adaptive probe holder (23) to drive the adaptive probe holder (23) to perform linear motion. The ultrasonic probes (24) are installed on the adaptive probe holders (23), and the adaptive probe holders (23) have adaptive pitch and adaptive tilt functions so that the ultrasonic probes (24) adapt to the surface contour of the workpiece.

2. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 1, characterized in that, The telescopic mechanism includes a primary telescopic mechanism (21) and several secondary telescopic mechanisms (22). The output end of the primary telescopic mechanism (21) is connected to the fixing part (223) of all the secondary telescopic mechanisms (22) to realize the rapid extension and active retraction of the ultrasonic probe (24). The output end of each secondary telescopic mechanism (22) is connected to an adaptive probe holder (23) to provide the ultrasonic probe (24) with a constant contact force with the external object.

3. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 2, characterized in that, The first-stage telescopic mechanism (21) includes a driving component (211), a fixed body (212), and a moving plate (213). The fixed body (212) is fixedly installed on the base (1). The cylinder of the driving component (211) is fixed on the fixed body (212). The output end of the driving component (211) is connected to the moving plate (213) to drive the moving plate (213) to move linearly relative to the fixed body (212). The moving plate (213) is fixedly connected to the fixing component (223) of the second-stage telescopic mechanism (22) to drive the second-stage telescopic mechanism (22) to move synchronously.

4. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 3, characterized in that, The secondary telescopic mechanism (22) includes a constant force component (221), a movable frame (222), and a fixing member (223) fixedly connected to the movable plate (213). The constant force component (221) is installed on the fixing member (223), and the output end of the constant force component (221) is connected to the movable frame (222) to provide a constant coupling force to the movable frame (222). The adaptive probe holder (23) is mounted on the movable frame (222).

5. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 4, characterized in that, The constant force assembly (221) includes a constant force spring (2211), a spring mounting base (2212), a guide shaft (2213), and a spring pressure plate (2214). The guide shaft (2213) is slidably inserted into the movable plate (213), and the first end of the guide shaft (2213) is fixedly connected to the spring mounting base (2212), and the second end of the guide shaft (2213) is fixedly connected to the movable frame (222). The first end of the constant force spring (2211) is fixed on the spring mounting base (2212), and the second end of the constant force spring (2211) is connected to the spring pressure plate (2214). The spring pressure plate (2214) is fixed on the movable plate (213).

6. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 4, characterized in that, The adaptive probe holder (23) includes a probe frame (231) and a probe outer frame (232). The ultrasonic probe (24) is mounted on the probe frame (231). The probe frame (231) is hinged to the probe outer frame (232) via a first pivot (233) to achieve the adaptive pitch function of the ultrasonic probe (24). The probe outer frame (232) is hinged to the movable frame (222) via a second pivot (234) to achieve the adaptive tilt function of the ultrasonic probe (24).

7. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 4, characterized in that, The detection module (2) also includes a universal ball bearing (25), which is disposed on the moving plate (213) to reduce friction during scanning.

8. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 4, characterized in that, The telescopic mechanism also includes a reset member (224), which is hinged to the moving plate (213) via a third pivot (225), and the first end of the reset member (224) is hinged to the moving frame (222) via a fourth pivot (226); A plunger (214) is provided on the fixed body (212). When the first-stage telescopic mechanism (21) retracts to the preset position, the second end of the reset member (224) abuts against the plunger (214) and rotates around the third rotating shaft (225), thereby pressing the first end of the reset member (224) back onto the movable frame (222), so that the movable frame (222) overcomes the force of the constant force component (221) and moves in the retraction direction.

9. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 1, characterized in that, The number of detection modules (2) is three, and the three detection modules (2) are distributed circumferentially along the base (1), with the central angle between two adjacent detection modules (2) being 70°.

10. The adaptive ultrasonic testing device for pressure vessel nozzles according to claim 1, characterized in that, The base (1) has a semi-circular structure.

Images