Ultrasonic sensor protection tube device for visualizing inside of invisible environment under high temperature and high radiation

Abstract

SOLUTION: To provide an ultrasonic sensor protection tube device including: an outside protection tube forming the appearance; an inner protection tube arranged in the inside of the outside protection tube away from the outside protection tube, an ultrasonic sensor arranged in the inside of the inner protection tube, and an ultrasonic sensor protection block arranged below the outside protection tube, the inside protection tube, and the ultrasonic sensor, the ultrasonic sensor protection block inducing focusing of ultrasonic waves.EFFECT: The present invention makes it possible to increase the accuracy of detecting physical deformations or defects of a structural material and to protect an ultrasonic sensor in an extreme invisible environment under high temperatures and high radiation.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an ultrasonic sensor protection tube device, and specifically, to an ultrasonic sensor protection tube device for visualizing the inside of a non-visible environment under high temperature and high radiation, which can ensure the durability of the ultrasonic sensor in an extremely opaque medium in a high temperature and high radiation environment, and at the same time improve the accuracy of ultrasonic waves.

Background Art

[0002] A sodium-cooled fast reactor (SFR) is a state-of-the-art reactor system that uses liquid sodium as a coolant. For the safe operation and radiation protection of a sodium-cooled fast reactor, periodic visual inspections and continuous monitoring of structural materials are essential. However, since liquid sodium has opaque characteristics, existing optical inspection methods applicable to transparent media are difficult to apply to the internal structures of a sodium-cooled fast reactor. To solve this problem, many research efforts have been made to develop ultrasonic-based technologies that enable visualization even in opaque environments. However, despite such developments, the degradation of data quality at high temperatures still remains a problem, and errors may potentially occur in detecting structural deformations.

[0003] A technique for detecting physical deformations and defects in structures in an opaque high-temperature and high-radiation environment such as a sodium-cooled fast reactor is known as an immersion flaw detection technique. The immersion flaw detection technique is a method of immersing an ultrasonic sensor in a sodium-cooled fast reactor. It is easy for transmitting and receiving ultrasonic waves and is advantageous in terms of signal accuracy. However, there is a problem that the ultrasonic sensor is exposed to high temperature and high radiation, shortening the life of the ultrasonic sensor.

[0004] Patent Document 1 discloses a double-rotating wave guide ultrasonic sensor device including a sensor unit that transmits and receives first and second ultrasonic signals to and from an object placed in an extreme environment at different angles to detect the position and shape of the object, a drive unit that performs double rotation on the transmission and reception positions of the first and second ultrasonic signals for attitude conversion, and a processing unit that processes and visualizes the transmitted and received first and second ultrasonic signals. Here, the first and second ultrasonic signals each include a vertical beam and a square beam.

[0005] According to the technology disclosed in Patent Document 1, the detection accuracy can be improved to a certain extent by using a double-rotating wave guide, but there is a limit to realizing an image video capable of detecting fine defects with a width of 0.5 mm or less.

[0006] The prior art is technical information that the inventor possessed for deriving the present invention or acquired during the derivation process of the present invention, and is not necessarily known technology publicly disclosed to the general public before the filing of the present invention.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] In order to solve the above problems, an object of the present invention is to provide an ultrasonic sensor protection tube device for internal visualization of a high-temperature and high-radiation invisible medium that can improve the accuracy of ultrasonic waves while ensuring the durability of the ultrasonic sensor.

[0009] Another object of the present invention is to provide an ultrasonic sensor protection tube device that can protect an ultrasonic sensor not only in a sodium-cooled fast reactor environment but also in an opaque high-temperature environment such as a lead-cooled reactor or a harmful environment, and at the same time can maximize its performance.

[0010] The problems to be solved by the present invention are not limited to those mentioned above, and other problems to be solved not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present invention pertains from the following description.

Means for Solving the Problems

[0011] The ultrasonic sensor protection tube device according to an embodiment of the present invention includes an external protection tube forming an outer appearance, an internal protection tube disposed inside the external protection tube and separated from the external protection tube, an ultrasonic sensor disposed inside the internal protection tube, and an ultrasonic sensor protection block disposed below the external protection tube, the internal protection tube, and the ultrasonic sensor to induce focusing of ultrasonic waves.

[0012] Further, the ultrasonic sensor protection tube device may further include a cooling gas injection pipe disposed inside the internal protection tube to inject cooling gas into the internal protection tube, and a cooling gas discharge pipe disposed inside the internal protection tube to discharge the heat-exchanged cooling gas to the outside of the internal protection tube.

[0013] Further, the ultrasonic sensor protection tube device may further include an ultrasonic sensor cable protection tube made of stainless steel, which is connected to the ultrasonic sensor and disposed so as to surround the ultrasonic sensor cable.

[0014] Further, the ultrasonic sensor protection tube device may further include a heat insulating material or a radiation shielding material inserted between the external protection tube and the internal protection tube.

[0015] Further, the ultrasonic sensor protection tube device may further include an ultrasonic focusing unit disposed below the ultrasonic sensor protection block and having a concave lens shape.

[0016] In this case, screw threads are formed on the outer peripheral surface of the ultrasonic sensor protection block and the inner peripheral surface of the external protection tube, respectively, so that the ultrasonic sensor protection block and the external protection tube can be detachably coupled to each other.

Advantages of the Invention

[0017] As described above, the ultrasonic sensor protection tube device according to the present invention can protect the ultrasonic sensor in an extreme non-visibility environment under high temperature and high radiation, and at the same time improve the physical deformation of the structural material and the accuracy of defect detection.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7A

Figure 7B

Figure 7C

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the present invention, the attached drawings may be shown in an exaggerated expression for the sake of distinctiveness and clarity from the prior art and for the convenience of understanding the technology. Further, the terms described below are terms defined in consideration of the functions in the present invention and may vary depending on the intention or convention of the user or operator. Therefore, the definitions of such terms must be made based on the technical content throughout this specification. On the other hand, the embodiments are merely illustrative matters of the components presented in the claims of the present invention and do not limit the scope of the present invention. The scope of rights must be interpreted based on the technical idea throughout the specification of the present invention.

[0020] Throughout the specification, when a certain configuration "includes" another configuration, this means that, unless otherwise stated to the contrary, it does not exclude other configurations but can further include other configurations.

[0021] Also, when a certain configuration is "connected", "joined" or "coupled" to another configuration, this means that not only when it is "directly connected", "directly joined" or "directly coupled", but also when it is "connected", "joined" or "coupled" with another configuration intervening therebetween. On the contrary, when a certain configuration is "directly connected", "directly joined" or "directly coupled" to another configuration, it must be understood that there is no other configuration in between.

[0022] Also, when directional terms such as "front", "rear", "top", "bottom", "left", "right", "one end", "the other end", "both ends" are used, this is used as an example in relation to the orientation of the disclosed drawings and should not be construed restrictively. When terms such as "first", "second" are used, this is a term for distinguishing each component and should not be construed restrictively.

[0023] To more clearly explain the features of the embodiments of the present invention, detailed descriptions of matters well-known to those of ordinary skill in the technical field to which the following embodiments belong are omitted. And detailed descriptions of parts not related to the description of the embodiments in the drawings are omitted.

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0025] FIG. 1 is an external perspective view showing the appearance of an ultrasonic sensor protection tube device according to an embodiment of the present invention, FIG. 2 is an internal configuration diagram showing the internal configuration of the ultrasonic sensor protection tube device according to an embodiment of the present invention, FIG. 3 is a diagram for explaining the function of a cooling gas injection pipe according to an embodiment of the present invention, FIGS. 4 and 5 are schematic diagrams for explaining the production of a test piece for testing the ultrasonic sensor protection tube device according to an embodiment of the present invention, FIG. 6 is a diagram showing the result of a C-scan defect detection test performed on a defect simulation test piece using the ultrasonic sensor protection tube device according to an embodiment of the present invention, FIG. 7A is a diagram showing a fine crack test piece, FIG. 7B is an optical micrograph of the fine crack test piece, and FIG. 7C is a diagram showing the result of a C-scan defect detection test performed on the fine crack test piece using the ultrasonic sensor protection tube device according to an embodiment of the present invention.

[0026] Referring to FIGS. 1 and 2, the ultrasonic sensor protection tube device 100 according to an embodiment of the present invention is used to detect physical deformations and defects of a structure in an opaque non-visible environment under high temperature and high radiation such as a sodium-cooled fast reactor (SFR). The ultrasonic sensor protection tube device 100 includes an external protection tube 300, an internal protection tube 400, an ultrasonic sensor 500, and an ultrasonic sensor protection block 600.

[0027] In this case, the ultrasonic sensor protection tube device 100 may further include a cooling gas injection pipe 200, a cooling gas discharge pipe 250, a tube lid 150, an ultrasonic sensor cable 510, an ultrasonic sensor cable protection tube 530, an ultrasonic contact medium (Couplant, 550), an ultrasonic focusing unit 610, an internal protection tube insertion groove 630, and an ultrasonic sensor support unit 650.

[0028] The external protection tube 300 is configured to form the appearance of the ultrasonic sensor protection tube device 100.

[0029] Since the external protection tube 300 is in direct contact with a high-temperature substance such as liquid sodium, it may be made of a metal material with low reactivity. In one embodiment, the external protection tube 300 may be made of stainless steel or an alloy such as SS316L. Also, the external protection tube 300 may be formed in a cylindrical shape with both ends open overall.

[0030] The internal protection tube 400 may be disposed inside the external protection tube 300 and separated from the external protection tube 300.

[0031] The diameter of the internal protection tube 400 may be formed smaller than that of the external protection tube 300. Therefore, a gap can be formed between the internal protection tube 400 and the external protection tube 300.

[0032] The internal protection tube 400 may be made of a metal material with good radiation shielding performance. In one embodiment, the internal protection tube 400 may be made of stainless steel or an alloy such as SS316L. Further, the internal protection tube 400 may be formed in a cylindrical shape with both ends open overall.

[0033] The tube lid 150 is a configuration for sealing the upper ends of the external protection tube 300 and the internal protection tube 400. The tube lid 150 can be formed to be detachable from the external protection tube 300 and the internal protection tube 400.

[0034] In one embodiment, the tube lid 150 may further include an O-ring or the like so that internal airtightness can be maintained as needed.

[0035] The tube lid 150 may be formed with a cooling gas injection pipe insertion hole (not shown) into which the cooling gas injection pipe 200 is inserted, a cooling gas discharge pipe communication hole (not shown) communicating with the cooling gas discharge pipe 250, and an ultrasonic sensor cable insertion hole (not shown) through which the ultrasonic sensor cable 510 passes.

[0036] The ultrasonic sensor 500 may be disposed inside the internal protection tube 400. The ultrasonic sensor 500 may be disposed at the center of the upper surface of the ultrasonic sensor protection block 600 with the ultrasonic contact medium 550 interposed therebetween.

[0037] The ultrasonic contact medium 550 is disposed between the ultrasonic sensor 500 and the ultrasonic sensor protection block 600 and is a configuration for minimizing ultrasonic attenuation.

[0038] The ultrasonic sensor cable 510 is a configuration for connecting the ultrasonic sensor 500 and an ultrasonic flaw detector (Pulser&Receiver, not shown).

[0039] The data measured by the ultrasonic sensor 500 is transmitted to the ultrasonic flaw detector via the ultrasonic sensor cable 510 connected to the ultrasonic sensor 500, and a C-scan for displaying the plane of the inspection object can be realized using the amplitude and TOF (Time of Flight) value of the received ultrasonic signal based on the transmitted data.

[0040] The ultrasonic sensor cable protection tube 530 is connected to the ultrasonic sensor 500 and is arranged to surround the ultrasonic sensor cable 510, protecting the ultrasonic sensor cable 510 and at the same time being a configuration for closely attaching the ultrasonic sensor 500 to the ultrasonic sensor protection block 600.

[0041] The ultrasonic sensor cable protection tube 530 may be formed of a stainless steel material surrounding the ultrasonic sensor cable 510.

[0042] The ultrasonic sensor cable protection tube 530 is coupled to the ultrasonic sensor 500 disposed at the lower part or is integrally formed with the ultrasonic sensor 500, and by pressing the ultrasonic sensor 500, the ultrasonic sensor 500 can be closely attached to the ultrasonic sensor protection block 600.

[0043] The ultrasonic sensor protection block 600 is disposed at the lower part of the external protection tube 300, the internal protection tube 400, and the ultrasonic sensor 500, and is a configuration for inducing the focusing of ultrasonic waves. The ultrasonic sensor protection block 600 supports the external protection tube 300, the internal protection tube 400, and the ultrasonic sensor 500, and enables smooth transmission and reception of ultrasonic waves by the ultrasonic sensor 500. In particular, it induces the focusing of ultrasonic waves to improve the accuracy.

[0044] The ultrasonic sensor protection block 600 may be made of nickel (Ni), which is a metal material with excellent contact performance with high-temperature liquid sodium, excellent heat resistance, and easy propagation of sound waves. The ultrasonic sensor protection block 600 is inserted between the external protection tube 300 and the internal protection tube 400 and can be detachably coupled to the external protection tube 300 and the internal protection tube 400.

[0045] In one embodiment, the ultrasonic sensor protection block 600 may be formed in a circular disk shape. Further, screw threads are respectively formed on the outer peripheral surface of the ultrasonic sensor protection block 600 and the inner peripheral surface of the external protection tube 300, and the ultrasonic sensor protection block 600 and the external protection tube 300 can be detachably screwed together.

[0046] The internal protection tube insertion groove 630 is a configuration for allowing the internal protection tube 400 to be inserted into and coupled to the ultrasonic sensor protection block 600. The internal protection tube insertion groove 630 may be formed on the upper surface of the ultrasonic sensor protection block 600 corresponding to the position where the internal protection tube 400 is coupled.

[0047] The ultrasonic sensor support portion 650 is a configuration for allowing the ultrasonic sensor 500 to be disposed on the ultrasonic sensor protection block 600. The ultrasonic sensor support portion 650 may be formed at the center of the upper surface of the ultrasonic sensor protection block 600 corresponding to the position where the ultrasonic sensor 500 is disposed.

[0048] The ultrasonic focusing portion 610 is a configuration for focusing ultrasonic waves. The ultrasonic focusing portion 610 is disposed below the ultrasonic sensor protection block 600 and can have a concave lens shape. The ultrasonic waves reflected from the surface of the detection target can be effectively focused by the ultrasonic focusing portion 610, improving the accuracy.

[0049] The cooling gas injection pipe 200 is disposed inside the internal protection tube 400 and is a configuration for injecting cooling gas into the internal protection tube 400.

[0050] The cooling gas is for protecting various components including the ultrasonic sensor 500 in a high-temperature environment such as a sodium-cooled fast reactor (SFR), and can maintain the ambient temperature of the ultrasonic sensor 500 near room temperature through heat exchange. As the cooling gas, helium can be used to minimize activation, but it is not limited thereto. The cooling gas injection pipe 200 may be inserted into the internal protection tube 400 through the tube lid 150, and its end may be arranged adjacent to the ultrasonic sensor protection block 600.

[0051] The cooling gas injection pipe 200 may be formed in a spiral shape to enhance efficiency by increasing the heat exchange area.

[0052] The cooling gas discharge pipe 250 is arranged inside the internal protection tube 400 and is configured to discharge the heat-exchanged cooling gas to the outside of the internal protection tube 400. The cooling gas injected into the internal protection tube 400 through the cooling gas injection pipe 200 maintains the ambient temperature of the ultrasonic sensor 500 near room temperature through heat exchange, and then can be discharged to the outside through the cooling gas discharge pipe 250.

[0053] The ultrasonic sensor protection tube device 100 can further include a temperature sensor (not shown) arranged inside the internal protection tube 400. The temperature sensor is configured to measure the temperature inside the internal protection tube 400 in real time during ultrasonic flaw detection. Based on the internal temperature measured in real time by the temperature sensor, the injection timing and injection amount of the cooling gas injected through the cooling gas injection pipe 200 can be determined.

[0054] The ultrasonic sensor protection tube device 100 can further include a heat insulating material or a radiation shielding material (not shown) inserted between the external protection tube 300 and the internal protection tube 400.

[0055] The heat insulation material is configured to protect the ultrasonic sensor 500 from a high-temperature environment. The heat insulation material can include, but is not limited to, an Aerogel insulator.

[0056] The radiation shielding material is configured to protect the ultrasonic sensor 500 from a high-radiation environment. The radiation shielding material can include, but is not limited to, metal hydrides, tungsten, boron carbide, etc.

[0057] <Test Example> A C-scan defect detection test was conducted using the ultrasonic sensor protection tube device according to an embodiment of the present invention. The C-scan defect detection test was performed on a defect simulation test piece and a fine crack test piece.

[0058] As shown in FIGS. 4 and 5, the defect simulation test piece for underwater visualization C-scan flaw detection was fabricated using an SS304L material, which is an SFR structural material, to a size of 20 mm × 20 mm and a thickness of 5 mm. As shown in Tables 1 and 2 below, the defect simulation test piece for underwater visualization C-scan flaw detection was etched with characters while varying the depth and width, or slit processed to produce six types of character-shaped slits (see FIG. 4 and Table 1) and twelve types of rectangular slits (see FIG. 5 and Table 2).

Table 1

Table 2

[0059] As shown in FIG. 7A, the fine crack test piece was formed by generating a fatigue crack in the central part using an SS304L material, which is an SFR structural material.

[0060] A C-scan defect detection test was conducted on the defect simulation test piece and the fine crack test piece using the ultrasonic sensor protection tube device according to an embodiment of the present invention (sensor types: 5 MHz, 10 MHz).

[0061] In order to classify the noise signals detected by the ultrasonic sensor, the distance between the ultrasonic sensor and the test piece was set to 35 mm. After setting a gate for a specific waveform in the signal from the test piece, it was set to detect fine defects based on waveform changes.

[0062] As shown in FIG. 6, as a result of the C-scan defect detection test on the defect replica test piece, according to the ultrasonic sensor protection tube device according to the embodiment of the present invention, a high-resolution defect image with a resolution of 0.5 mm to 2.0 mm could be obtained. Also, a C-scan image database for artificial intelligence learning was constructed by repeated measurements.

[0063] As shown in FIGS. 7B and 7C, according to the ultrasonic sensor protection tube device according to the embodiment of the present invention, for the fine fatigue cracks formed in the fine defect test piece, a high-resolution defect image corresponding to the optical micrograph (FIG. 7B) could be obtained.

[0064] As described above, the ultrasonic sensor protection tube device according to the present invention can protect the ultrasonic sensor in an extreme non-visible environment under high temperature and high radiation, and at the same time improve the physical deformation of the structural material and the accuracy of defect detection.

[0065] As described above, the present invention has been described with reference to the embodiments shown in the drawings, but this is merely illustrative, and it should be understood that various modifications and equivalent other embodiments are possible based on ordinary knowledge in the technical field to which the present invention pertains. Therefore, the true technical protection scope of the present invention must be determined by the scope of the claims described below based on the specific content of the invention described above.

Industrial Applicability

[0066] The present invention relates to an ultrasonic sensor protection tube device and is applicable to the industrial field related to immersion flaw detection technology applied to an opaque high-temperature and high-radiation environment.

Explanation of Reference Numerals

[0067] 100: Ultrasonic sensor protection tube device for high-temperature and high-radiation environment 150: Tube lid 200: Cooling gas injection pipe 250: Cooling gas discharge pipe 300: External protection tube 400: Internal protection tube 500: Ultrasonic sensor 510: Ultrasonic sensor cable 530: Ultrasonic sensor cable protection tube 550: Ultrasonic contact medium 600: Ultrasonic sensor protection block 610: Ultrasonic focusing part 630: Internal protection tube insertion groove 650: Ultrasonic sensor support part

Claims

1. An external protective tube that forms the exterior; an inner protective tube disposed inside the outer protective tube and spaced apart from the outer protective tube; an ultrasonic sensor disposed inside the inner protective tube; an ultrasonic sensor protection block disposed under the outer protection tube, the inner protection tube, and the ultrasonic sensor to induce focusing of ultrasonic waves; 2. An ultrasonic sensor protection tube apparatus comprising:

2. a cooling gas injection pipe disposed inside the inner protective tube and configured to inject a cooling gas into the inner protective tube; a cooling gas exhaust pipe disposed inside the inner protective tube and configured to exhaust the heat-exchanged cooling gas to the outside of the inner protective tube; The ultrasonic sensor protection tube device according to claim 1 , further comprising:

3. an ultrasonic sensor cable protection tube made of stainless steel, connected to the ultrasonic sensor and arranged to surround the ultrasonic sensor cable; The ultrasonic sensor protection tube device according to claim 1 , further comprising:

4. a heat insulating material or radiation shielding material inserted between the outer protective tube and the inner protective tube; The ultrasonic sensor protection tube device according to claim 1 , further comprising:

5. an ultrasonic focusing part having a concave lens shape, the ultrasonic focusing part being disposed under the ultrasonic sensor protection block; The ultrasonic sensor protection tube device according to claim 1 , further comprising:

6. 2. The ultrasonic sensor protection tube device according to claim 1, wherein a screw thread is formed on an outer peripheral surface of the ultrasonic sensor protection block and an inner peripheral surface of the external protection tube, so that the ultrasonic sensor protection block and the external protection tube are detachably connected to each other.

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