A sodium-cooled fast reactor vessel non-destructive testing robot

Abstract

The application provides a sodium-cooled fast reactor vessel nondestructive testing robot, which comprises a pre-tightening support mechanism, a transmission mechanism, a driving mechanism and a detection device, the pre-tightening support mechanism is used for keeping the nondestructive testing robot in contact with the wall surface of the main vessel and the wall surface of the protective vessel when the nondestructive testing robot is in the interlayer of the vessel, the transmission mechanism is connected with the pre-tightening support mechanism to provide support force for the pre-tightening support mechanism, the driving mechanism is used for moving the nondestructive testing robot in the interlayer of the vessel, and the detection device is used for detecting the damage of the wall surface of the vessel. The nondestructive testing robot is designed to be highly compact and flexible, can keep stable in the interlayer space of 100 mm, can move straight, translate laterally and turn, thereby realizing the complex motion mode of the grid path, can use the detection device to detect the weld of the vessel in detail, judge whether the weld has defects or not, thereby providing a technical basis for the subsequent residual life prediction and risk prevention and control.

Description

Technical Field

[0001] This invention relates to the field of nuclear power technology, specifically to a non-destructive testing robot for sodium-cooled fast reactor containers. Background Technology

[0002] The reactor vessel of a sodium-cooled fast reactor (SNCR) is a core component of the SNCR system, consisting of the main vessel, protective vessel, argon gas layer, and insulation layer. It serves as a crucial safety barrier for the reactor. Because the reactor vessel is irreplaceable throughout the entire lifespan of the fast reactor, it is subjected to the high temperature, high pressure, and transient loads of the reactor coolant during operation, as well as the neutron radiation environment from core leaks. These factors can lead to gradual material aging and the potential for defect initiation, with existing defects also posing a risk of propagation. To improve reactor safety, when technically feasible, it is necessary to conduct regular in-service inspections of the reactor vessel throughout its service life. This includes identifying and assessing the presence of defects in the main vessel structure, whether these defects are within tolerance limits, and the rate of defect propagation. Timely assessment of the reactor vessel's structural integrity and safety, as well as prediction of remaining lifespan, provides a technical basis for risk control. Therefore, conducting in-service inspections of the SNCR of a sodium-cooled fast reactor ensures its safe operating status and performance stability, thereby guaranteeing the overall safety and economic efficiency of the reactor.

[0003] Currently, some countries internationally have implemented in-service inspection robots for fast reactor reactor vessels. The MIR remote-controlled inspection vehicle designed by the French team for the "Phoenix One" fast reactor, and the multi-functional in-service inspection ISI vehicle developed by Mitsubishi Heavy Industries in Japan for the "Manjushri" fast reactor, have both been practically tested on their respective domestic fast reactors. In recent years, India has also conducted research on corresponding robot technologies and supporting equipment. The in-service inspection prototype developed by the Indira Gandhi Atomic Energy Research Centre for the 500MWe prototype fast reactor has been able to operate stably under experimental conditions. In contrast, research on in-service inspection of fast reactor reactor vessels in China is still in its early stages, and systematic in-service inspection and evaluation throughout the entire life cycle of the reactor vessel is not yet possible, posing certain risks to the long-term safe operation of fast reactors. Compared with similar reactor types abroad, domestic fast reactors generally have higher shutdown temperatures and more limited inspection space. These special limitations greatly increase the difficulty of implementing in-service inspection work and hinder the improvement of technology in this field. Although we can draw on international experience in testing solutions and equipment, the development of in-service inspection equipment that is independently controllable and adapted to the actual field environment must still rely on domestic research and development to meet the unique technical challenges and operational requirements, due to the significant differences in structural design and operating environment of domestic fast reactors.

[0004] Since the China Experimental Fast Reactor (CEFR), my country's first sodium-cooled fast reactor, achieved criticality in 2010, and the 600MW demonstration fast reactor project in Xiapu was completed and put into operation in 2023, China's construction progress in the field of sodium-cooled fast reactors has accelerated significantly. Based on international nuclear power operation experience, my country is about to enter a critical stage where the demand for in-service inspections of fast reactors will increase significantly. With the successive completion and commissioning of more fast reactor facilities, the future demand for in-service inspections of reactor vessels will only increase daily. Therefore, developing in-service inspection robots for sodium-cooled fast reactor reactor vessels suitable for my country not only has broad economic prospects but is also related to the long-term development of the nuclear power industry in the fast reactor era and national strategic security. Summary of the Invention

[0005] The purpose of this invention is to propose a non-destructive testing robot for sodium-cooled fast stack containers, which can move stably within the narrow internal space of the stack container.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A non-destructive testing robot for a sodium-cooled fast stack container includes a pre-tightening support mechanism, a transmission mechanism, a drive mechanism, and a detection device. The pre-tightening support mechanism ensures that the non-destructive testing robot maintains close contact with the walls of the main container and the protective container when it is located within the interlayer of the stack container. The transmission mechanism is connected to the pre-tightening support mechanism to provide support force, ensuring close contact between the non-destructive testing robot and the walls of the main container and the protective container. The drive mechanism moves the non-destructive testing robot within the interlayer of the stack container. The detection device is used to detect damage to the stack container wall. The detection device, drive mechanism, and transmission mechanism are mounted on the pre-tightening support mechanism.

[0007] The pre-tightening support mechanism includes an upper support surface, a lower support surface, four sets of sliding units, and casters. The four sets of sliding units are positioned between the upper and lower support surfaces, supporting the upper support surface and allowing it to move vertically. Each sliding unit includes a guide post, a connecting rod, a vertical slider, a horizontal slider, and a horizontal slide rail. The guide post is located between the upper and lower support surfaces. One end of the connecting rod is fixed to the vertical slider, which slides on the guide post. The other end of the connecting rod is fixed to the horizontal slider, which slides on the horizontal slide rail. The connecting rod is fixed to the upper support surface. The casters are located on the outer sides of the upper and lower support surfaces. The pre-tightening support mechanism uses linearly movable sliders and connecting rods. The horizontal slider moves linearly, driving the connecting rod to propel the vertical slider in a linear motion, thus enabling the non-destructive testing robot to extend and compress in the height direction. By setting the casters to contact the container wall, reliable and continuous contact between the robot and the wall is ensured, stabilizing it within the interlayer while allowing it to move. The "up" and "down" of the upper and lower support surfaces are for convenience only and do not refer to orientation. Since the non-destructive testing robot is located in the interlayer between the main container and the protective container, "up" and "down" are only for convenience to describe the direction towards the main container and the protective container. Therefore, "up" and "down" can also be reversed.

[0008] The transmission mechanism is connected to the sliding unit of the pre-tightening support mechanism, driving the upper support surface to move up and down.

[0009] The transmission mechanism includes a lifting motor, a gear transmission unit, a first connecting plate, a first lead screw guide rail, a second connecting plate, and a second lead screw guide rail. The shaft of the lifting motor is connected to the gear transmission unit, which is connected to both the first and second lead screw guide rails to drive them to rotate. The second connecting plate is mounted on the first lead screw guide rail and reciprocates on it via a lead screw nut pair. Two horizontal sliders are connected to both ends of the first connecting plate. The second connecting plate is mounted on the second lead screw guide rail and reciprocates on it via a lead screw nut pair. Two other horizontal sliders are connected to both ends of the first connecting plate.

[0010] The transmission mechanism also includes a guide rail 1 and a guide rail 2. A connecting plate is fitted onto the guide rail 1, and the guide rail 1 is arranged parallel to the lead screw guide rail 1. The connecting plate 2 is fitted onto the guide rail 2, and the guide rail 2 is arranged parallel to the lead screw guide rail 2.

[0011] The transmission mechanism also includes a guide rail three, a connecting plate two is fitted on the guide rail three, and the guide rail three is set between the guide rail two and the lead screw guide rail two and is parallel to both.

[0012] The middle part of connecting plate two is bent into a U-shape towards connecting plate one.

[0013] The middle part of the connecting plate two is fitted onto the guide rail three.

[0014] The gear transmission unit includes bevel gear 1, bevel gear 2, connecting rod, bevel gear 3, bevel gear 4, and bevel gear 5. Bevel gear 1 is fixed on the shaft of the lifting motor and meshes with bevel gear 2. Bevel gear 2 and bevel gear 3 are fixed at both ends of the connecting rod, and bevel gear 3 meshes with bevel gear 4 and bevel gear 5, respectively. Bevel gear 4 is connected to lead screw guide rail 1, and bevel gear 5 is connected to lead screw guide rail 2.

[0015] The drive mechanism includes a drive unit and a steering unit. The drive unit includes a wheel support, a tire axle, a drive motor, a wheel hub, and a spring suspension. The wheel support is fixed to the lower support surface by the spring suspension. The tire axle is fixed in the mounting holes of the wheel support. The wheel hub is rotatably mounted on the tire axle. The drive motor is installed inside the wheel hub.

[0016] The wheel rims are fitted with rubber-coated tires.

[0017] The supporting force provided by the lead screw should be equal to or greater than F calculated by equation (1). AX value: (1), Among them, F AXThe supporting force provided by the lead screw, μ is the coefficient of friction between the wheel assembly and the wall, G is the weight of the non-destructive testing robot, and α is the angle between the connecting rod and the horizontal direction. By experimenting with the supporting force provided by the lead screw, good contact is ensured between the caster wheels, the wheels of the drive mechanism, and the walls of the main and protective containers, preventing the non-destructive testing robot from slipping or even falling. After obtaining the supporting force provided by the lead screw, an appropriate lifting motor can be selected based on the transmission efficiency.

[0018] The steering unit includes a steering motor and a steering gear. A drive pinion is fixedly connected to the output shaft of the steering motor, and the drive pinion meshes with the steering gear for transmission. The steering gear is fixedly mounted on the tire axle. The steering motor drives the steering gear through the drive pinion, thereby driving the tire axle to rotate around its own axis to achieve steering.

[0019] The detection device is an ultrasonic probe assembly and / or a high-temperature industrial camera assembly.

[0020] The ultrasonic probe assembly is set on the lower support surface. The ultrasonic probe assembly includes an ultrasonic probe, a probe fixing platform, a push rod, and a stud. The ultrasonic probe is fixed on the probe fixing platform, and the probe fixing platform is fixed to the stud. The ultrasonic fixing platform is set below the lower support surface. The stud passes through the guide hole of the lower support surface and slides up and down in the guide hole. The movable end of the push rod is fixed on the probe fixing platform, driving the probe fixing platform to reciprocate up and down.

[0021] The non-destructive testing robot moves at equal intervals along a rectangular trajectory on the wall of the main container.

[0022] High-temperature industrial cameras are cooled by air.

[0023] Cables are installed on the non-destructive testing robot.

[0024] The above-described solution of the present invention has at least the following beneficial effects: This patent addresses the key issues of in-service inspection of sodium-cooled fast reactor containers. Specifically, it employs an integrated structural design of a wheeled robot with a pre-tensioning support mechanism, a drive mechanism, and a transmission mechanism, taking into account the confined space they face. This achieves the following technical effects: (1) The robot is designed to be highly compact and flexible, and can move in a straight line, translate laterally, and turn within a 100mm space, and can realize a variety of complex motion modes such as grid paths. (2) The selected ultrasonic probe assembly can meet the requirements of weld inspection of reactor vessels. The high-temperature camera with air cooling can maintain a good working condition. The overall inspection system has good engineering applicability. (3) This study not only broke through the key technology of robot motion and detection integration in narrow space, but also provided an important equipment foundation for realizing in-service inspection of the entire life cycle of the reactor container; Attached Figure Description

[0025] Figure 1 This is a structural schematic diagram of a non-destructive testing robot.

[0026] Figure 2 This is a schematic diagram of the working principle of the pre-tightening support mechanism of a non-destructive testing robot.

[0027] Figure 3 This is a schematic diagram of the transmission mechanism of a non-destructive testing robot.

[0028] Figure 4 This is a schematic diagram of the force analysis of the pre-tightening support mechanism.

[0029] Figure 5 This is a schematic diagram of the gear transmission unit of a non-destructive testing robot.

[0030] Figure 6 This is a schematic diagram of a non-destructive testing robot entering a stack container.

[0031] Figure 7 This is a schematic diagram of the pre-tightening support mechanism rising after the non-destructive testing robot enters the stack container.

[0032] Figure 8 This is a schematic diagram of the drive mechanism of a non-destructive testing robot.

[0033] Figure 9 This is a schematic diagram of the ultrasonic probe assembly of a non-destructive testing robot.

[0034] Figure 10 This is a structural schematic diagram of the high-temperature industrial camera component of a non-destructive testing robot.

[0035] Figure 11 This is a schematic diagram of the auxiliary facilities for a non-destructive testing robot.

[0036] Figure 12 This is a diagram showing the trajectory of a non-destructive testing robot within a stack container. Detailed Implementation

[0037] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0038] A non-destructive testing robot for sodium-cooled fast-stacking containers, such as Figure 1As shown, the system includes a pre-tightening support mechanism, a transmission mechanism, a drive mechanism, and a detection device. The pre-tightening support mechanism ensures that the non-destructive testing robot remains in close contact with the walls of the main container 100 and the protective container 200 when it is located within the interlayer of the stack container. The transmission mechanism is connected to the pre-tightening support mechanism to provide support force, ensuring that the non-destructive testing robot remains in close contact with the walls of the main container and the protective container. The drive mechanism moves the non-destructive testing robot within the interlayer of the stack container. The detection device is used to detect damage to the stack container wall. The detection device, drive device, and transmission device are mounted on the pre-tightening support mechanism.

[0039] like Figure 1 As shown, the pre-tightening support mechanism includes an upper support surface 1, a lower support surface 2, and four sets of sliding units disposed between the upper support surface 1 and the lower support surface 2, located at the four corners. The four sets of sliding units are used to support the upper support surface 1 and move the upper support surface 1 up and down. The sliding unit includes a guide post 3, a connecting rod 4, a vertical slider 5, a horizontal slider 6, and a horizontal slide rail 7. The guide post 3 is disposed between the upper and lower support surfaces. One end of the connecting rod 4 is fixed to the vertical slider 5, and the vertical slider 5 slides on the guide post 3. The other end of the connecting rod 4 is fixed to the horizontal slider 6, and the horizontal slider 6 slides on the horizontal slide rail 7. The connecting rod 4 is fixed to the upper support surface 1.

[0040] Universal wheels 8 are installed on the outer sides of the upper and lower support surfaces, making contact with the walls of the main container 100 and the protective container 200. By setting universal wheels to contact the container walls, it is ensured that the robot can maintain reliable and continuous contact with the walls, making it stable within the interlayer, while also enabling it to move.

[0041] The schematic diagram of the pre-tightening support mechanism is as follows: Figure 2 As shown, due to the left-right symmetry of the mechanism, one side is selected for study. This mechanism has 3 moving members, 4 lower pairs, 0 higher pairs, 0 virtual constraints, and 0 local degrees of freedom. The results calculated using the in-plane mechanism degree-of-freedom formula are as follows, where n is the number of moving members, pl is the number of lower pairs, ph is the number of higher pairs, p' is the number of virtual constraints, and F' is the number of local degrees of freedom: F=3×n-(2×pl+ph-p')-F'=3×3-(2×4+0-0)-0=1.

[0042] It can be seen that the pre-tightening support mechanism has one degree of freedom. The horizontal movement of the connecting rod 4, the vertical slider 5, and the horizontal slider 6 causes the connecting rod 4 to expand outward, which in turn drives the vertical slider 5 to move vertically. The vertical slider 5 is connected to the upper support surface of the non-destructive testing robot, so that the entire robot is in an outward expansion state.

[0043] like Figure 3As shown, the transmission mechanism includes a lifting motor 9, a gear transmission unit, a connecting plate 10, a lead screw guide rail 11, a connecting plate 2 12, a lead screw guide rail 2 13, a smooth rod guide rail 14, a smooth rod guide rail 2 15, and a smooth rod guide rail 3 16. The rotating shaft of the lifting motor 9 is connected to the gear transmission unit, which is connected to the lead screw guide rail 11 and the lead screw guide rail 2 13 respectively to drive them to rotate. The connecting plate 10 is sleeved on the lead screw guide rail 11 and reciprocates on it through a lead screw nut pair. Two horizontal sliders 6 are connected to both ends of the connecting plate 10. The connecting plate 2 12 is sleeved on the lead screw guide rail 2 13 and reciprocates on it through a lead screw nut pair. Two other horizontal sliders 6 are connected to both ends of the connecting plate 2 12. Meanwhile, connecting plate 10 is fitted onto guide rail 14, which is parallel to lead screw guide rail 11; connecting plate 2 12 is fitted onto guide rail 2 15, which is parallel to lead screw guide rail 2 13. Connecting plate 2 12 is also fitted onto guide rail 3 16, which is positioned between and parallel to guide rail 2 15 and lead screw guide rail 2 13. Connecting plate 2 12 is configured such that its middle portion is bent into a U-shape towards connecting plate 10. The middle portion of connecting plate 2 12 is fitted onto guide rail 3 16. Lead screw guide rail 1 11, lead screw guide rail 2 13, guide rail 1 14, guide rail 2 15, and guide rail 3 16 are all fixed to the lower support surface 2 by support 33.

[0044] The lifting motor transmits torque to two sets of movable pre-tightening support mechanisms through a transmission mechanism. This mechanism ensures that the upper and lower omnidirectional wheels and the lower drive wheel of the non-destructive testing robot always maintain a certain positive pressure with the container wall, keeping each wheel system tightly attached to the wall surface, thus ensuring the adhesion and movement of the drive wheels. Figure 4 As shown, the supporting force F provided by the lead screw AX The direction of the value is as indicated by the arrow, and the direction of gravity G is also as indicated by the arrow. The use of two sets of symmetrical pre-tensioned support mechanisms significantly improves the robot's motion stiffness and stability.

[0045] To obtain this positive pressure, the support force provided by the lead screw needs to be equal to or greater than F calculated by equation (1). AX value: (1), Among them, F AX The supporting force provided by the lead screw, μ is the coefficient of friction between the wheel assembly and the wall surface, G is the weight of the non-destructive testing robot, and α is the angle between the link and the horizontal direction. The wheel assembly refers to omnidirectional wheels and / or drive wheels. The lead screw is a single lead screw guide.

[0046] like Figure 5As shown, the gear transmission unit includes bevel gear 17, bevel gear 28, connecting rod 19, bevel gear 30, bevel gear 41, and bevel gear 52. Bevel gear 17 is fixed on the shaft of the lifting motor 9 and meshes with bevel gear 28. Bevel gear 28 and bevel gear 30 are fixed at both ends of the connecting rod 19, and bevel gear 30 meshes with bevel gear 41 and bevel gear 52, respectively. Bevel gear 421 is connected to lead screw guide rail 11, and bevel gear 52 is connected to lead screw guide rail 23. The lifting motor 9 drives lead screw guide rail 1 and lead screw guide rail 2 to rotate through the gear transmission unit, thereby driving the pre-tensioning support mechanism to move and providing support force to the pre-tensioning support mechanism.

[0047] Gear transmission is the most common transmission method, offering advantages such as high precision, high efficiency, and strong load-bearing capacity, making it particularly suitable for devices requiring compact structures. Non-destructive testing robots utilize a transmission method combining gears and lead screws, such as... Figure 5 As shown, the entire transmission mechanism consists of two sets of bevel gears, two sets of lead screw guides, and three sets of guide rods, and is powered by a single motor, effectively reducing space occupation. The torque output by the motor is transmitted to the lead screw-guide rod combination mechanism, converting rotational motion into precise horizontal linear motion, which in turn drives the slider-connecting rod preload support mechanism to achieve directional movement. This design cleverly utilizes a single drive source to synchronously control two symmetrically distributed transmission units, which not only significantly improves the system's integration and motion consistency but is also suitable for applications with high requirements for spatial layout and motion synchronization.

[0048] When a non-destructive testing robot enters a stack container, such as Figure 6 As shown, after the operation of the pre-tightening support mechanism and the transmission mechanism, the non-destructive testing robot operates as follows: Figure 7 As shown, the pre-tensioning support mechanism of the non-destructive testing robot consists of a linearly movable slider and connecting rod. When the lifting motor transmits torque to the lead screw, the lead screw rotates and pushes the horizontal slider in a linear motion, thereby driving the connecting rod transmission and pushing the upper slider in a linear motion, thus realizing the robot's extension and compression in the height direction. Furthermore, utilizing the self-locking characteristics and high friction of the lead screw transmission itself, a continuous and stable positive pressure is provided to the wheel assembly, ensuring reliable contact with the wall surface and preventing slippage or falling. Figure 7 As shown.

[0049] like Figure 8As shown, the drive mechanism includes a drive unit and a steering unit. The drive unit includes a wheel support 23, a tire axle 24, a drive motor 25, a wheel hub 26, and a spring suspension 27. The wheel support 23 is fixed to the lower support surface 2 via the spring suspension 27. The tire axle 24 is fixed in the mounting holes of the wheel support 23. The wheel hub 26 is rotatably mounted on the tire axle 24, and the drive motor 25 is installed inside the wheel hub 26. A rubber-coated tire 28 is fitted over the wheel hub. The steering unit includes a steering motor 29 and a steering gear 30. The drive pinion on the steering motor 29 meshes with the steering gear 30. The steering gear 30 is fixedly mounted on the tire axle 24. The steering motor 29 drives the steering gear 30 through the drive pinion, driving the tire axle 24 to rotate around its own axis to achieve steering. The drive mechanism is driven by the drive motor and the steering motor for movement and rotation. To maximize space saving and meet compact requirements, the drive motor is installed inside the wheel hub, while the outer side uses a rubber-coated tire, which provides sufficient traction and also partially reduces vibration. The steering function is achieved by a steering motor, which enables precise rotation of the wheels around the axle via gear transmission, thereby adjusting the robot's direction of travel. Furthermore, the spring suspension structure design adapts to minor undulations and unevenness on the wall surface, ensuring that the rubber-coated tires maintain close contact with the wall surface under complex working conditions, effectively transmitting driving force and preventing loss of control due to detachment.

[0050] like Figure 1 As shown, the detection device is an ultrasonic probe assembly 32 and / or a high-temperature industrial camera assembly 31.

[0051] The ultrasonic probe assembly 32 is mounted on the lower support surface 2. For example... Figure 9 As shown, the ultrasonic probe assembly 32 includes an ultrasonic probe 321, a probe fixing platform 322, a push rod 323, and a stud 324. The ultrasonic probe 321 is fixed on the probe fixing platform 322, which is fixed to the stud 324. The ultrasonic fixing platform 322 is located below the lower support surface 2. The stud 324 passes through a guide hole in the lower support surface 2 and slides up and down in the guide hole. The movable end of the push rod 323 is fixed on the probe fixing platform 322, driving the probe fixing platform 322 to reciprocate up and down. The ultrasonic probe achieves linear reciprocating motion driven by the push rod, enabling it to accurately approach and leave the detection surface. With the controllable pressure provided by the push rod, the probe can be stably pressed against the wall surface, ensuring good coupling, thereby improving the accuracy of ultrasonic signal transmission and the reliability of detection results.

[0052] The industrial camera in the high-temperature industrial camera assembly 31 is cooled by compressed argon gas.

[0053] like Figure 10As shown, the high-temperature industrial camera assembly 31 includes an industrial camera 311 and a cooling unit. The cooling unit includes a cooling box 312, a cooling pipe 313, and a cooling gas source (compressed argon). The industrial camera 311 is disposed in the cooling box 312, and the cooling gas source supplies cooling gas to the cooling box through the cooling pipe 313. The industrial camera 311 has a lens 3111 and a supplementary light source 3112.

[0054] like Figure 11 As shown, the main task of the non-destructive testing robot is to enter the interlayer between the main container 100 and the protective container 200 from the reactor cone top cover, and to inspect the longitudinal and circumferential welds of the main container and the protective container. At the same time, it can transmit the ultrasonic probe detection data and the high-temperature camera image data to the external control console in real time for further analysis and processing. Therefore, auxiliary facilities such as control rooms and guide rails can be set up outside the protective container according to the actual situation of the reactor. The control room can be equipped with cable shafts, control devices, etc.

[0055] The non-destructive testing robot is designed as a cuboid, and all structural components must be able to be installed compactly to accommodate the 100mm gap requirement of the stack container interlayer.

[0056] Based on this, such as Figure 1 As shown, along the long axis of the non-destructive testing robot, the high-temperature industrial camera assembly, the drive mechanism, and the ultrasonic probe assembly are installed in sequence. The transmission mechanism is arranged along the long axis. The drive mechanism is installed between the connecting plate one and the connecting plate two of the transmission mechanism. The connecting plate two is set as a U-shaped clearance to avoid the ultrasonic probe assembly, so that the ultrasonic probe assembly can be placed on the outside of the connecting plate two.

[0057] The drive mechanism enables horizontal rolling and 360° rotation, allowing the robot to perform horizontal linear movement, overall lateral movement, and flexible steering. This meets the scanning requirements of the ultrasonic probe, which can move at equal intervals along a predetermined grid path on the surface of the workpiece. Figure 12 As shown, the ultrasonic response signal echoes associated with defects at each location are recorded, thus forming a three-dimensional image that reflects the distribution, shape, and size of internal defects in the workpiece. This scanning method is suitable for detecting internal defects, thickness variations, and delamination, and the results are intuitive and easy to interpret.

[0058] Due to the spatial limitations of the non-destructive testing robot, it does not have a dedicated scanning frame for ultrasonic probes. Therefore, a drive mechanism propels the robot to perform scanning along a prescribed grid path. This drive mechanism enables the robot to move in straight lines and turn, allowing it to complete various complex motion modes such as grid trajectories. Furthermore, it precisely controls motion accuracy and performance to ensure the imaging quality of both ultrasonic and visual inspections.

[0059] Ultrasonic probes and high-temperature industrial cameras are two types of inspection equipment that robots can carry. To meet the visual inspection requirements of welds inside reactor vessels, the high-temperature industrial camera is mounted at a designated height on the robot's body to ensure that its field of view can completely cover the area to be inspected and obtain clear images.

[0060] Both the ultrasonic probe and the industrial camera were purchased from the market based on the size requirements of the non-destructive testing robot.

[0061] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or equivalent to the scope of this invention are included in this invention.

Claims

1. A non-destructive testing robot for sodium-cooled fast-stacking containers, characterized in that, The system includes a pre-tightening support mechanism, a transmission mechanism, a drive mechanism, and a detection device. The pre-tightening support mechanism ensures that the non-destructive testing robot maintains close contact with the walls of the main container and the protective container when it is located within the interlayer of the stack container. The transmission mechanism is connected to the pre-tightening support mechanism to provide support force, ensuring close contact between the non-destructive testing robot and the walls of the main container and the protective container. The drive mechanism moves the non-destructive testing robot within the interlayer of the stack container. The detection device is used to detect damage to the stack container wall. The detection device, drive mechanism, and transmission mechanism are mounted on the pre-tightening support mechanism. The pre-tensioning support mechanism includes an upper support surface, a lower support surface, four sets of sliding units, and casters. The four sets of sliding units are located between the upper and lower support surfaces. These units support the upper support surface and allow it to move up and down. Each sliding unit includes a guide post, a connecting rod, a vertical slider, a horizontal slider, and a horizontal slide rail. The guide post is located between the upper and lower support surfaces. One end of the connecting rod is fixed to the vertical slider, which slides on the guide post. The other end of the connecting rod is fixed to the horizontal slider, which slides on the horizontal slide rail. The connecting rod is fixed to the upper support surface. The casters are located on the outer sides of the upper and lower support surfaces. The transmission mechanism is connected to the sliding unit of the pre-tightening support mechanism, driving the upper support surface to move up and down; The transmission mechanism includes a lifting motor, a gear transmission unit, a connecting plate 1, a lead screw guide rail 1, a connecting plate 2, and a lead screw guide rail 2. The shaft of the lifting motor is connected to the gear transmission unit, which is connected to both lead screw guide rail 1 and lead screw guide rail 2 to drive them to rotate. The connecting plate is mounted on lead screw guide rail 1 and reciprocates on it via a lead screw and nut pair. Two horizontal sliders are connected to both ends of the connecting plate 1. The connecting plate 2 is mounted on lead screw guide rail 2 and reciprocates via a lead screw and nut pair. The auxiliary gear reciprocates on the lead screw guide rail 2, and the two ends of the connecting plate 1 are respectively connected to two other horizontal sliders; the gear transmission unit includes bevel gear 1, bevel gear 2, connecting rod, bevel gear 3, bevel gear 4, and bevel gear 5. Bevel gear 1 is fixed on the lifting motor shaft and meshes with bevel gear 2. Bevel gear 2 and bevel gear 3 are respectively fixed at both ends of the connecting rod. Bevel gear 3 meshes with bevel gear 4 and bevel gear 5 respectively. Bevel gear 4 is connected to lead screw guide rail 1, and bevel gear 5 is connected to lead screw guide rail 2. The drive mechanism includes a drive unit and a steering unit. The drive unit includes a wheel mount, a tire axle, a drive motor, a wheel hub, and a spring suspension. The wheel mount is fixed to the lower support surface by the spring suspension. The tire axle is fixed in the mounting holes of the wheel mount. The wheel hub is rotatably mounted on the tire axle. The drive motor is installed inside the wheel hub. The steering unit includes a steering motor and a steering gear. A drive pinion is fixedly connected to the output shaft of the steering motor. The drive pinion meshes with the steering gear for transmission. The steering gear is fixedly mounted on the tire axle.

2. The non-destructive testing robot according to claim 1, characterized in that, The supporting force provided by the lead screw should be equal to or greater than F calculated by equation (1). AX value: （1）， Among them, F AX The supporting force provided by the lead screw, μ is the coefficient of friction between the wheel assembly and the wall, G is the weight of the non-destructive testing robot, and α is the angle between the connecting rod and the horizontal direction.

3. The non-destructive testing robot according to claim 1, characterized in that, The detection device is an ultrasonic probe assembly and / or a high-temperature industrial camera assembly.

4. The non-destructive testing robot according to claim 3, characterized in that, The ultrasonic probe assembly is set on the lower support surface. The ultrasonic probe assembly includes an ultrasonic probe, a probe fixing platform, a push rod, and a stud. The ultrasonic probe is fixed on the probe fixing platform, and the probe fixing platform is fixed to the stud. The ultrasonic fixing platform is set below the lower support surface. The stud passes through the guide hole of the lower support surface and slides up and down in the guide hole. The movable end of the push rod is fixed on the probe fixing platform, driving the probe fixing platform to reciprocate up and down.

Images