A device and method for underwater measurement of roundness error of radioactive pipes

Abstract

The present application relates to the technical field of nuclear industry detection, and particularly relates to a kind of radioactive pipe roundness error underwater measuring device and method, measuring device includes: guide column, coaxial measurement through-hole is arranged in middle part, the measurement through-hole can be crossed by the pipe to be measured test tube;Rotary driver, with the guide column transmission connection, for driving the guide column rotates along its own axis;Sealing cover, sealing cover is arranged outside the rotary driver;Displacement sensor, located above the guide column, for measuring the displacement of the side wall of the pipe to be measured test tube relative to the side wall of the guide column when the guide column rotates relative to the pipe to be measured test tube, can be measured in underwater to the diameter data of any position of single irradiation test pipe, and output corresponding roundness error, to realize the underwater long-distance accurate measurement roundness error of irradiation test pipe. The measuring method is based on the aforementioned measuring system.

Description

Technical Field

[0001] This invention relates to the field of nuclear industry testing technology, specifically to an underwater measuring device and method for the roundness error of radioactive pipes. Background Technology

[0002] Reactor irradiation production is a crucial evaluation indicator for reactor core layout and an important means of preparing medical isotopes, developing new reactor materials, and producing high-performance semiconductor materials. Reactor irradiation testing involves inserting elongated, tubular irradiation test tubes into the fuel assemblies, which are then fed into the reactor along with the fuel assemblies to receive irradiation. After being exposed to a certain level of nuclear irradiation, the irradiation test tubes may exhibit effects such as swelling and creep. In a certain nuclear reactor irradiation production research project, it is necessary to conduct underwater measurements of the roundness error of several irradiation test tubes to promptly obtain performance data of their cladding materials. Summary of the Invention

[0003] To address the technical problem of underwater measurement of the roundness error of irradiated test tubes, this invention provides an underwater measurement device and method for the roundness error of radioactive tubes. This device and method can measure the diameter data of a single irradiated test tube at any position underwater and output the corresponding roundness error. This enables precise underwater long-distance measurement of the roundness error of irradiated test tubes, providing high measurement accuracy and ease of operation.

[0004] This invention is achieved through the following technical solution:

[0005] In a first aspect, the present invention provides an underwater measuring device for the roundness error of radioactive pipes, comprising: a guide post having a measuring through hole coaxially disposed in the middle, the measuring through hole being able to allow the test pipe to pass through; a rotary actuator, which is connected to the guide post for driving the guide post to rotate along its own axis; a sealing cover disposed outside the rotary actuator; and a displacement sensor located above the guide post for measuring the displacement of the sidewall of the test pipe relative to the sidewall of the guide post when the guide post rotates relative to the test pipe.

[0006] The underwater measuring device for the roundness error of radioactive pipes provided by this invention has a measuring through hole coaxially arranged in the middle of the guide column for the pipe to be tested to pass through, and a displacement sensor is arranged above the guide column. When measurement is required, the measuring device is lowered into the water tank where the pipe to be tested is located, and then the pipe to be tested is inserted into the measuring through hole, so that the measuring part of the displacement sensor is in close contact with the side wall of the pipe to be tested. At this time, the guide column is driven to rotate along its own axis by a rotary actuator, so as to drive the displacement sensor to rotate relative to the guide column. Thus, the change in the radial dimension of the pipe to be tested is detected by the change in the degree of the displacement sensor, and finally the roundness error of the pipe to be tested is obtained.

[0007] The rotary drive outer sealing cover is equipped with a sealing cover to prevent water from the pool from entering the working space of the rotary drive, thus ensuring the normal operation of the rotary drive.

[0008] Therefore, the underwater measurement device for the roundness error of radioactive tubes provided by this invention can measure the diameter data of a single irradiated test tube at any position underwater and output the corresponding roundness error. This enables precise underwater long-distance measurement of the roundness error of the irradiated test tube, detection of roundness changes after the irradiated test tube leaves the reactor, and timely acquisition of data on the irradiated cladding material. It not only has high measurement accuracy but is also easy to operate.

[0009] In an optional embodiment, a guide block is further included, wherein a guide hole is provided in the center of the guide block to provide guidance for the test tube under test. The guide hole is coaxially arranged with the measuring through hole to guide the test tube under test through the guide block, so as to ensure that the test tube under test can quickly and accurately enter and exit the measuring through hole.

[0010] In an optional embodiment, a fixed support is further included, the guide post being fixedly and throughly inserted into the bottom of the fixed support, and the guide block being disposed on the top of the fixed support to ensure the relative positional accuracy of the guide block and the guide post.

[0011] In an optional embodiment, a measuring block and an elastic guide rail are disposed between the guide post and the guide block; the displacement sensor is connected to the measuring block, the measuring block is connected to the elastic guide rail, and the length direction of the elastic guide rail is perpendicular to the axial direction of the guide post, so that the displacement sensor can accurately reflect the change in the radial dimension of the tested tube.

[0012] In an optional embodiment, the rotary actuator is connected to the guide post via a transmission gear, so that the rotational torque output by the rotary actuator can be transmitted to the guide post through gear transmission, which can ensure the reliability of torque transmission.

[0013] In an optional embodiment, the upper end of the transmission gear is provided with a manual drive unit, which is used to drive the transmission gear in the event of failure of the rotary drive, thereby manually driving the guide column to rotate to continue the measurement and avoid interruption in the measurement process.

[0014] In an optional embodiment, a reduction gear is also included, the transmission gear being connected to the guide post via the reduction gear to prevent the guide post from rotating too fast.

[0015] In an optional embodiment, the guide post is externally fitted with a driven gear, which meshes with the reduction gear to ensure the reliability of torque transmission between the reduction gear and the guide post.

[0016] In an optional embodiment, the sealing cover is equipped with a gas pressurization nozzle, and a pressure sensor is provided inside the sealing cover. The pressure sensor is used to detect the air pressure inside the sealing cover, so as to improve the waterproof performance of the sealing cover by pressurized gas inside the sealing cover, so that the measuring device can perform measurements in areas with high water pressure.

[0017] Secondly, the present invention provides an underwater method for measuring the roundness error of radioactive pipes, based on the aforementioned underwater measuring device for the roundness error of radioactive pipes, comprising the following steps:

[0018] S10. Fill the sealing cover of the underwater measuring device for the roundness error of radioactive pipes with gas at a set pressure.

[0019] S20. Place the underwater measuring device for the roundness error of the radioactive pipe into the water tank where the test pipe is located, and insert the test pipe into the guide column;

[0020] S30. Monitor the gas pressure inside the sealing cover in real time and ensure that the gas pressure inside the sealing cover is within the set threshold range;

[0021] S40. After the displacement sensor detects the size of the test tube at the preset position, it drives the guide column to rotate and lowers the test tube according to the set step size for measurement.

[0022] During the rotation of the guide column, the test tube under test is lowered, causing the displacement sensor to move along the axial direction of the guide tube under test to measure the diameter data at any position of the irradiation test tube, and then the roundness error is obtained by using multiple diameter data.

[0023] The underwater measurement method for the roundness error of radioactive pipes provided by this invention, based on the aforementioned underwater measurement device for the roundness error of radioactive pipes, can measure the diameter data of a single irradiated test pipe at any position underwater and output the corresponding roundness error. This enables precise underwater long-distance measurement of the roundness error of the irradiated test pipe, detection of roundness changes after the irradiated test pipe leaves the reactor, and timely acquisition of data on the irradiated cladding material.

[0024] The present invention has the following advantages and beneficial effects:

[0025] 1. The underwater measuring device for the roundness error of radioactive tubes provided by this invention has a measuring through hole coaxially arranged in the middle of the guide column for the tube to be tested to pass through, and a displacement sensor is arranged above the guide column. The guide column is driven to rotate along its own axis by a rotary actuator, so as to drive the displacement sensor to rotate relative to the guide column. Thus, the change in the radial dimension of the tube to be tested is detected by the change in the degree of the displacement sensor, and finally the roundness error of the tube to be tested is obtained. In addition, the outer sealing cover of the rotary actuator is equipped with a sealing cover to prevent water in the pool from entering the working space of the rotary actuator, which can ensure the normal operation of the rotary actuator. Therefore, it can realize the measurement of the diameter data of a single irradiated test tube at any position underwater and output the corresponding roundness error, thereby realizing the accurate measurement of the roundness error of the irradiated test tube underwater over a long distance. It not only has high measurement accuracy, but also is easy to operate.

[0026] 2. The underwater measurement method for the roundness error of radioactive pipes provided by this invention, based on the aforementioned underwater measurement device for the roundness error of radioactive pipes, can measure the diameter data of a single irradiated test pipe at any position underwater and output the corresponding roundness error. This enables precise underwater long-distance measurement of the roundness error of the irradiated test pipe, detection of roundness changes after the irradiated test pipe leaves the reactor, and timely acquisition of data on the irradiated cladding material. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0028] In the attached diagram:

[0029] Figure 1 This is a cross-sectional structural schematic diagram of the underwater measuring device for the roundness error of radioactive pipes according to an embodiment of the present invention;

[0030] Figure 2 This is a partial disassembly perspective view of the underwater measuring device for the roundness error of radioactive pipes according to an embodiment of the present invention.

[0031] Figure label:

[0032] 1-Guide post, 2-Measuring through hole, 3-Test tube under test, 4-Rotary actuator, 5-Sealing cover, 6-Displacement sensor, 7-Guide block, 8-Guide hole, 9-Fixed support, 10-Measuring block, 11-Elastic guide rail, 12-Transmission gear, 13-Manual drive unit, 14-Reduction gear, 15-Driven gear, 16-Drive gear, 17-Gas pressurizing nozzle, 18-Pressure sensor, 19-Mounting base, 20-Connecting support. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Unless otherwise specified, embodiments and features in the embodiments of this invention can be combined with each other.

[0035] Example 1

[0036] Combination Figure 1 and Figure 2 This embodiment provides an underwater measuring device for the roundness error of radioactive pipes, comprising: a guide post 1 with a measuring through hole 2 coaxially arranged in the middle, the measuring through hole 2 allowing the test tube 3 to pass through; a rotary actuator 4, which is connected to the guide post 1 for driving the guide post 1 to rotate along its own axis; a sealing cover 5 disposed outside the rotary actuator 4; and a displacement sensor 6 located above the guide post 1 for measuring the displacement of the sidewall of the test tube 3 relative to the sidewall of the guide post 1 when the guide post 1 rotates relative to the test tube 3.

[0037] To ensure that the test tube 3 can be quickly inserted into the measuring through hole 2, a guide block 7 is also included. The guide block 7 has a guide hole 8 in its center to guide the test tube 3. The guide hole 8 is coaxially arranged with the measuring through hole 2. That is, both the guide plate and the guide post 1 have coaxially formed tapered holes at their upper ends, with the larger hole at the top and the smaller hole at the bottom, and the two holes are aligned for positioning and insertion of the test tube. The guide block 7 guides the test tube 3, ensuring that it can quickly and accurately enter and exit the measuring through hole 2.

[0038] It is understood that the system also includes a fixed support 9, with the guide post 1 fixedly and throughly inserted into the bottom of the fixed support 9, and the guide block 7 disposed on the top of the fixed support 9 to ensure the relative positional accuracy of the guide block 7 and the guide post 1.

[0039] For the displacement sensor 6, an LVDT displacement sensor 6 is used in this embodiment. To ensure that the displacement sensor 6 can work properly, in this embodiment, a measuring block 10 and an elastic guide rail 11 are provided between the guide post 1 and the guide block 7; the displacement sensor 6 is connected to the measuring block 10, and the measuring block 10 is connected to the elastic guide rail 11. The length direction of the elastic guide rail 11 is perpendicular to the axis of the guide post 1. Specifically, for the corresponding test conditions, the size and spring constant of the spring in the elastic guide rail 11 are strictly calculated to ensure that at the corresponding depth underwater (e.g., 8 meters underwater), the pipe with a diameter of only 10 mm is pressed onto the measuring block 10 with a suitable force (the measuring block 10 is stationary). If the spring force is too large, the pipe cannot open the measuring space formed by the elastic guide rail 11 and the measuring block 10; if the spring force is too small, the measuring block 10 cannot be reliably pressed onto the surface of the tested pipe 3, resulting in distorted measurement data.

[0040] The rotary driver 4 can be a commonly used motor or a pneumatic motor, etc. In this embodiment, a servo motor is used as the rotary driver 4.

[0041] For ease of installation, a mounting base 19 is also provided in this embodiment. The upper end of the guide post 1 is rotatably connected to the fixed support 9, while its lower end is also inserted through the mounting base 19. The guide post 1 is rotatably connected to the mounting base 19. Correspondingly, the rotary driver 4 and the sealing cover 5 are also mounted on the mounting base 19.

[0042] It should be understood that, under normal circumstances, the measuring block 10, the elastic guide rail 11, and the displacement sensor 6 are provided in two sets, with the two sets of measuring components symmetrically distributed on both sides of the guide post 1 along its axial direction to ensure the accuracy of the measurement data. Of course, other types of displacement sensors 6 can also be used.

[0043] For the transmission connection between the rotary driver 4 and the guide post 1, a transmission mechanism such as a sprocket and chain mechanism, a synchronous belt pulley mechanism, or a gear mechanism can be used. In this embodiment, gear transmission is preferred. That is, the rotary driver 4 is connected to the guide post 1 through a transmission gear 12, so that the rotational torque output by the rotary driver 4 can be transmitted to the guide post 1 through gear transmission, which can ensure the reliability of torque transmission.

[0044] It also includes a reduction gear 14, through which the transmission gear 12 is connected to the guide post 1 to prevent the guide post 1 from rotating too fast.

[0045] Meanwhile, a driven gear 15 is sleeved on the outer drive of the guide post 1, and the driven gear 15 meshes with the reduction gear 14 to ensure the reliability of torque transmission between the reduction gear 14 and the guide post 1. It is also known that a drive gear 16 is sleeved on the output shaft of the rotary actuator 4, and the drive gear 16 meshes with the transmission gear 12.

[0046] Specifically, the rotary actuator 4 is sealed inside the sealing cover 5, which is fixedly connected to the mounting base 19 via the connecting support 20. The output shaft of the rotary actuator 4 is connected to the rotating shaft of the drive gear 16 via a rotatable coupling that is sealed to the sealing cover 5. The rotating shaft of the drive gear 16 is rotatably connected to the top of the connecting support 20. The transmission gear 12 and the reduction gear 14 are respectively located at both ends of the transmission shaft, with the upper end of the transmission shaft rotatably connected to the top of the connecting support 20 and the lower end rotatably connected to the mounting base 19.

[0047] Based on this, a manual drive unit 13 is provided at the upper end of the transmission gear 12. The manual drive unit 13 is used to connect with the drive handle so that the transmission gear 12 can be manually driven in the event of failure of the rotary driver 4, thereby manually driving the guide column 1 to rotate and continue to complete the measurement, thus avoiding interruption in the measurement process.

[0048] Furthermore, if the actuator 4 malfunctions and continues to rotate in the same direction, the control cable may become entangled in the test tube 3, or even break. In this situation, it is necessary to immediately stop the control system and manually drive the transmission gear 12 to rotate the cable away from the test tube 3 in the opposite direction, thereby ensuring the safety of underwater operations and the radioactive pipe.

[0049] It is understood that the shape of the manual drive part 13 is determined according to the shape of the drive handle head, and can be a groove / hole such as an internal hexagonal groove / through hole, a slot / hole, or a cross groove / hole, or a protrusion such as a multi-sided protrusion, a slotted protrusion, or a triangular protrusion. In this embodiment, the manual drive part 13 is a circular protrusion with multiple recesses and notches in the circumferential direction.

[0050] Furthermore, the sealing cover 5 is equipped with a gas pressurizing nozzle 17, and a pressure sensor 18 is provided inside the sealing cover 5. The pressure sensor 18 is used to detect the air pressure inside the sealing cover 5, so as to improve the waterproof performance of the sealing cover 5 by using the pressurized gas inside the sealing cover 5, so that the measuring device can perform measurements in areas with high water pressure.

[0051] It should be noted that the sealing cover 5 is equipped with an O-ring and a pressure plug to provide a sealing space for the rotary actuator 4, and it needs to be pressurized before operation. When the pressure value of the pressure sensor 18 is lower than the set threshold, it indicates that the sealing cover 5 is flooded. At this time, the system alarm will remind the operator to remove the device in time to avoid the rotary actuator 4 from failing due to water immersion.

[0052] In addition, the sealing cover 5 is made of metal, such as stainless steel, which not only shields against liquids and ensures the normal operation of the rotary drive 4 (servo motor), but also absorbs radiation, preventing interference from radiation to the servo motor encoder. Ultimately, this allows the use of a regular servo motor to replace the expensive waterproof and radiation-resistant motor, improving the overall economy of the equipment and saving on equipment and maintenance costs.

[0053] In summary, the underwater measuring device for the roundness error of radioactive pipes provided in this embodiment has a measuring through hole 2 coaxially arranged in the middle of the guide column 1 for the test pipe 3 to pass through, and a displacement sensor 6 is arranged above the guide column 1. When measurement is required, the measuring device is lowered into the water tank where the test pipe 3 is located (on the existing platform in the waste tank loading well), and then the test pipe 3 is inserted into the measuring through hole 2, so that the measuring part of the displacement sensor 6 is in close contact with the side wall of the test pipe 3 under the action of the elastic guide rail 11. At this time, the guide column 1 is driven to rotate along its own axis by the rotary driver 4, so as to drive the displacement sensor 6 to rotate relative to the guide column 1. Thus, the change in the radial dimension of the test pipe 3 is detected by the change in the degree of the displacement sensor 6, and finally the roundness error of the test pipe 3 is obtained.

[0054] The rotary drive 4 has an outer sealing cover 5, which prevents water from the pool from entering the working space of the rotary drive 4, thus ensuring the normal operation of the rotary drive 4.

[0055] Therefore, the underwater measurement device for the roundness error of radioactive tubes provided in this embodiment can measure the diameter data of a single irradiated test tube at any position underwater and output the corresponding roundness error. This allows for precise underwater long-distance measurement of the roundness error of irradiated test tubes on the existing platform in the spent fuel pool loading well, enabling the detection of roundness changes after the irradiated test tubes leave the reactor, and thus timely acquisition of data on the irradiated cladding material. The device is not only highly accurate but also easy to operate.

[0056] Example 2

[0057] This embodiment provides an underwater method for measuring the roundness error of radioactive pipes, based on the underwater measuring device for the roundness error of radioactive pipes described in Embodiment 1, including the following steps:

[0058] S10. Fill the sealing cover 5 of the underwater measuring device for the roundness error of radioactive pipes with gas at a set pressure.

[0059] S20. Place the underwater measuring device for the roundness error of the radioactive pipe into the water tank where the test pipe 3 is located, and insert the test pipe 3 into the guide column 1.

[0060] S30. Monitor the gas pressure inside the sealing cover 5 in real time and ensure that the gas pressure inside the sealing cover 5 is within the set threshold range;

[0061] S40, after the displacement sensor 6 detects the size of the test tube 3 at the preset position, it drives the guide column 1 to rotate and lowers the test tube 3 according to the set step size for measurement.

[0062] Specifically, once the displacement sensor 6 detects the preset position dimension at the lower end of the test tube 3, the rotary driver 4 is activated, and the test tube continues to descend. For every 10mm descent of the test tube 3, the guide column 1 rotates one revolution in either the forward or reverse direction until 20 diameter data points are collected. The step size of the descent of the test tube 3 and the number of measurements are set according to actual needs.

[0063] It is important to note that the measurement rotation method is one revolution clockwise and one revolution counterclockwise, and so on. This method can ensure the collection of measurement data for the entire circumference while avoiding the risk of the cable getting tangled in the test tube 3 or even breaking the cable or tube by rotating several revolutions in one direction.

[0064] During the rotation of the guide column 1, the test tube 3 is lowered, causing the displacement sensor 6 to move along the axial direction of the guide tube to measure the diameter data at any position of the irradiation test tube. The measured roundness data can be fitted to an image of that position, and the roundness error at that position can be obtained through a preset roundness error calculation program.

[0065] The underwater measurement method for the roundness error of radioactive tubes provided in this embodiment, based on the aforementioned underwater measurement device for the roundness error of radioactive tubes, can measure the diameter data of a single irradiated test tube at any position underwater and output the corresponding roundness error. This enables precise underwater long-distance measurement of the roundness error of the irradiated test tube, detection of roundness changes after the irradiated test tube leaves the reactor, and timely acquisition of data on the irradiated cladding material.

[0066] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An underwater measuring device for the roundness error of radioactive pipes, characterized in that, include: The guide post (1) has a measuring through hole (2) coaxially arranged in the middle, and the measuring through hole (2) allows the test tube (3) to be tested to pass through; A rotary actuator (4) is connected to the guide post (1) for driving the guide post (1) to rotate along its own axis; A sealing cover (5) is provided outside the rotary drive (4) and is equipped with a gas pressurizing nozzle (17). A pressure sensor (18) is provided inside the sealing cover (5) to detect the gas pressure inside the sealing cover (5). The displacement sensor (6) is located above the guide post (1) and is used to measure the displacement of the side wall of the test tube (3) relative to the side wall of the guide post (1) when the guide post (1) rotates relative to the test tube (3). The guide block (7) has a guide hole (8) in the middle to provide guidance for the test tube (3) to be tested. The guide hole (8) is coaxially arranged with the measuring through hole (2). Among them, a measuring block (10) and an elastic guide rail (11) are provided between the guide post (1) and the guide block (7). The displacement sensor (6) is connected to the measuring block (10), the measuring block (10) is connected to the elastic guide rail (11), and the length direction of the elastic guide rail (11) is perpendicular to the axis of the guide post (1). It also includes a fixed support (9), the guide post (1) is fixedly and through inserted into the bottom of the fixed support (9), and the guide block (7) is disposed on the top of the fixed support (9).

2. The underwater measuring device for the roundness error of radioactive pipes according to claim 1, characterized in that, The rotary driver (4) is connected to the guide post (1) via a transmission gear (12).

3. The underwater measuring device for the roundness error of radioactive pipes according to claim 2, characterized in that, The upper end of the transmission gear (12) is provided with a manual drive unit (13), which is used to drive the drive handle.

4. The underwater measuring device for the roundness error of radioactive pipes according to claim 2, characterized in that, It also includes a reduction gear (14), and the transmission gear (12) is connected to the guide post (1) through the reduction gear (14).

5. The underwater measuring device for the roundness error of radioactive pipes according to claim 4, characterized in that, The guide post (1) is externally fitted with a driven gear (15), which meshes with the reduction gear (14).

6. An underwater method for measuring the roundness error of radioactive pipes, characterized in that, The underwater measuring device for the roundness error of radioactive pipes according to any one of claims 1 to 5 includes the following steps: S10. Fill the sealing cover (5) of the underwater measuring device for the roundness error of radioactive pipes with gas at a set pressure. S20. Place the underwater measuring device for the roundness error of the radioactive pipe into the pool where the test pipe (3) is located, and insert the test pipe (3) into the guide column (1); S30. Monitor the gas pressure inside the sealing cover (5) in real time and ensure that the gas pressure inside the sealing cover (5) is within the set threshold range; S40. After the displacement sensor (6) detects the size of the test tube (3) at the preset position, it drives the guide column (1) to rotate and lowers the test tube (3) according to the set step size to perform the measurement.

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