JP5422463B2 - Non-destructive inspection method in the reactor pressure vessel lower mirror - Google Patents

Description

  The present invention relates to a nondestructive inspection in a lower mirror portion of a reactor pressure vessel, which is one of the main equipment of a nuclear power plant.

  Many industrial products undergo various inspections to ensure their safety and security. In particular, in nuclear power plants, after starting operation, the operation is periodically stopped and equipment is inspected, and ensuring safe operation of the nuclear power plant is given priority over anything else.

  In recent years, if a defect is discovered in a periodic inspection, etc., the equipment's soundness is evaluated by measuring the size of the defect by nondestructive inspection instead of immediately repairing or replacing it. The setting or repair time is decided.

  Regular inspections are also carried out in the reactor pressure vessel (hereinafter referred to as RPV), which is one of the main equipment of nuclear power plants, or in the welded part of the reactor internal structure attached to the RPV. As one of the methods for performing non-destructive inspection, visual inspection (VT) is performed in which a camera is inserted into the RPV and the surface state of the welded portion is confirmed. Many other methods such as an ultrasonic flaw detection test (UT) and an overcurrent flaw detection test (ECT) are carried out by adopting a method of accessing an inspection device from the inside of the furnace on the welding operation side. For example, as in Patent Document 1, an apparatus that ultrasonically inspects the welded portion of the RPV in the circumferential direction is described.

  However, in recent years, it has become possible to carry out inspections not only from the inside of the furnace on the construction side, but also from outside the furnace via the RPV, due to the advancement of inspection apparatuses and the development of new inspection methods. In the in-furnace inspection, the inside of the RPV is usually filled with the reactor water and the working environment is underwater. However, since the out-of-furnace inspection is an aerial operation, it is considered that the workability is improved. For example, in Patent Document 2, the inspection position is obtained by measuring the inclination angle of the vessel penetration portion with respect to the reactor pressure vessel wall surface in the inspection outside the reactor. Moreover, in patent document 3, it describes that the position of an apparatus is determined using an ultrasonic wave when visually inspecting a welding part as a submerged inspection apparatus in a furnace.

  The RPV lower mirror has a hemispherical shape with a plate thickness of about 150 to 200 mm and a diameter of 6000 to 7000 mm, and a diameter of 200 mm for penetration of internal structures such as a control rod drive guide tube (hereinafter referred to as CRD housing). It has a structure in which about 100 to 200 holes are provided.

Japanese Patent Laid-Open No. 08-226987 JP 2008-039622 A Japanese Patent Laid-Open No. 02-95246

  The shape of the welded part to be inspected at the RPV lower mirror part is complicated and the surroundings are narrow, so the inspection conditions are limited in terms of accessibility, contactability, etc., and the inspection range and accuracy are limited, which is sound. It is assumed that it will be difficult to obtain sufficient information for sex assessment.

  The problem to be solved is to improve the inspection accuracy of the narrow and complex welded portion of the lower part of the reactor pressure vessel.

  In the inspection of the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, nondestructive inspection is performed from two directions from the inside of the RPV (inside the reactor) and from the outside of the RPV (outside of the reactor). Or the inspection method which measures a range and matches the measurement result by said 2 methods.

  The inspection method of the present invention can cover each non-inspectable range by applying two methods of in-furnace inspection and out-of-furnace inspection in an inspection performed in a narrow and complicated shape portion such as an RPV lower mirror part. Moreover, since each inspection result is matched, a more detailed evaluation of a defect can be performed and inspection accuracy can be improved.

It is sectional drawing of the reactor pressure vessel lower mirror part used as implementation object. It is sectional drawing of the welding part which is implementation object. It is a structural example of an in-furnace inspection apparatus. It is an example of a measurement by an in-furnace inspection device. It is explanatory drawing of the position coordinate setting in a furnace. It is a structural example of an in-core inspection apparatus. It is explanatory drawing of a furnace position coordinate setting. It is an example of a measurement by an out-of-core inspection device. It is explanatory drawing of the position coordinate setting inside and outside a furnace.

  Each embodiment will be described with reference to the drawings.

  As described in the following examples, in-furnace inspection is performed from the inside of the furnace on the welding side for defects found in the welded portion of the reactor internal structure attached to RPV or RPV, particularly the lower mirror portion. The measurement accuracy is improved by applying two methods of out-of-furnace inspection performed from the outside of the furnace via the RPV to the weld and comprehensively measuring the size or range of the defect.

  In addition, in the inspection performed in a narrow and complicated portion such as the RPV lower mirror part, by applying the two methods of in-furnace inspection and out-furnace inspection, it is possible to cover each non-inspectable range.

  In addition, it is possible to reduce the time for defect identification by performing inspection from outside or inside the furnace based on the position coordinates of defects obtained by in-furnace or outside furnace inspection.

  At this time, in order to match the position coordinates of the defect obtained from the in-furnace inspection result and the out-of-furnace inspection result, the same coordinate axis is provided in advance in the furnace and outside the furnace at the time of inspection, thereby improving the work efficiency at the time of defect evaluation. Plan.

  Moreover, since each inspection result is matched, more detailed evaluation of a defect can be performed.

  Furthermore, since the vicinity of the RPV serving as the inspection place is narrow and has a high dose, the exposure time of the worker can be reduced by shortening the work time.

  FIG. 1 is a cross-sectional view of an RPV lower mirror portion of a nuclear power plant that is an object of implementation of the inspection method of this embodiment. As described above, in the RPV lower mirror portion, the cylindrical CRD housing 2 or the like passes through the RPV 1 which is a hemispherical structure, and the CRD housing and the RPV are fixed by the CRD stub 3. Part A will be described in detail with reference to FIG.

  FIG. 2 is a cross-sectional view of a welded portion that is an object of implementation. Since the CRD stub circumference and the RPV inner surface side are fixed by the welded portions 4a and 4b as shown in the A detailed view of FIG. 2, the shape of the welded portion to be inspected is three-dimensionally changed and complicated. Recognize. In the embodiment described below, the welds 4a and 4b of the CRD stub 3 are targeted for inspection, but the present invention can also be applied to other RPVs or welds of in-furnace structures attached to RPVs.

  Further, in the embodiment described below, in order to match the position coordinates of the defect obtained by nondestructive inspection from the inside of the furnace and from the outside of the furnace, a CRD housing that penetrates inside and outside the furnace is used, Although the same position coordinate origin is provided, it can be applied to other in-furnace structures.

  The inspection apparatus of each embodiment includes an inspection unit that inspects an inspection object, a recording unit that receives and records information from the inspection unit, and a display unit that displays the received information. The recording unit is a recording medium such as a database server, a hard disk, or a memory. The display device is a display or the like. For example, an ultrasonic wave that performs ultrasonic nondestructive inspection has a configuration represented by Patent Document 2, and has an ultrasonic probe (ultrasonic sensor) that transmits and receives ultrasonic waves as an inspection unit. . It also has a control mechanism that controls the timing of sending and receiving ultrasonic waves transmitted and received from the ultrasonic probe. The control mechanism is a computer, and performs ultrasonic scanning by a phased array method or the like by executing a program on the CPU. In the case of visual inspection (VT), the inspection unit is a camera. In the case of eddy current inspection (ECT), the inspection unit is an excitation coil, a detection coil, or an excitation / detection coil. Moreover, it has a control mechanism which controls a coil and a control mechanism is a computer.

  In Example 1, first, nondestructive inspection from the inside of the furnace is performed by in-furnace ultrasonic flaw inspection, and the detection and dimension of the defect are measured. Next, ultrasonic nondestructive inspection is performed from the outside of the furnace based on the defect position coordinates obtained by the in-furnace inspection. Finally, the defect shape is evaluated by matching both inspection results. Here, ultrasonic flaw detection (UT) is adopted for nondestructive inspection in the furnace, but only one method among visual inspection (VT), eddy current flaw inspection (ECT), and ultrasonic flaw inspection (UT) is used. Either a combination of methods or a combination of three methods may be applied.

  FIG. 3 is a schematic diagram of the configuration of the in-core ultrasonic device used in the in-core inspection. The ultrasonic inspection apparatus main body 5 is seated on the upper part of the CRD housing, and an ultrasonic sensor 7 attached to the tip of the arm part by moving the arm part 6 attached to the side of the main body up and down and rotating or contracting around the apparatus. Is scanned while transmitting and receiving ultrasonic waves, and the part is inspected.

  Further, the positioning plate 8 attached to the device seating portion is composed of guide pins 9a and 9b, a pressing plate 10 and a guide plate 11, and the guide plate 11 is pushed out from the seated CRD housing toward the adjacent CRD stub. It is possible to clamp (fix) between the two housings.

  When a defect is found in a periodic inspection or the like, it is necessary to measure the size and range of the defect. Next, a process of measuring the found defects using the in-furnace inspection apparatus will be described with reference to FIG.

FIG. 4 is an example of measurement by the in-furnace inspection apparatus. The tube center axis direction of the CRD housing from where the ultrasonic inspection apparatus body 5 is seated is z _0, and r ₀ is the distance from the tube center of the CRD housing where the ultrasonic inspection apparatus body 5 is seated to the tube center of the adjacent CRD housing. The distance from the rotation center of the arm 6 to the ultrasonic sensor 7 is r _1, and the rotation angle of the arm 6 from the direction of the adjacent CRD housing to which the positioning plate 8 is connected is θ _1. The distance from the place where the main body 5 is seated to the defect position in the tube central axis direction of the CRD housing is measured as z ₁ . The measurement of these positions is performed by a normal measuring device as in the case of controlling the position of a robot arm or the like. The measured position information is recorded in the database of the in-furnace inspection device.

  FIG. 5 is an explanatory diagram for setting the position coordinates in the furnace. Coordinates are set based on the data measured as described above. First, in the present apparatus, a reference coordinate axis is provided centering on a portion where the tube central axis 12 of the seated CRD housing intersects with the upper surface 13 of the CRD housing. Specifically, the vertical direction of the seated CRD housing is the z-axis, the direction connecting the centers of the two clamped CRD housings is the r-axis, and the reference coordinate axis is composed of the rotation angle θ about the z-axis. is there.

When the reference coordinate axis is used, the defect position coordinates are as shown in the right of FIG. 5, the angle between the r axis and the inspection device arm part is θ ₁ , the distance r ₁ from the center of the CRD housing to the tip of the arm, and the top surface of the CRD housing By measuring the distance z ₁ from the defect to the defect, the defect position coordinates (r ₁ , z ₁ , θ ₁ ) can be specified.

Next, an out-of-furnace inspection apparatus that performs ultrasonic flaw inspection from the outer surface side of the RPV based on the defect position coordinates (r ₁ , z ₁ , θ ₁ ) and its process will be described.

  The apparatus shown in FIG. 6 is attached to the carriage 15 running on the heat insulating material 14 installed on the floor outside the RPV, the arm part 16 having a turning and raising / lowering function at the head part of the carriage, and further to the tip of the arm part. The ultrasonic sensor 17 is used. Further, it has a function of clamping between the two CRD housings by pushing the guide plates 18a, 18b left and right from the apparatus main body.

  Using the out-of-furnace inspection apparatus, scanning is performed with the ultrasonic sensor in contact with the outer surface of the RPV, and the flaw detection inspection of the part is performed by transmitting and receiving ultrasonic waves.

Here, since the defect position coordinates (r ₁ , z ₁ , θ ₁ ) are specified by the in-furnace inspection, an out-of-furnace inspection apparatus is used based on the defect position coordinates (r ₁ , z ₁ , θ ₁ ). Access and conduct ultrasonic inspection from outside of furnace.

  First, it travels to the vicinity of the CRD housing where the defect is detected, and the same CRD housing as the two CRD housings clamped when the reference coordinate axis is provided in the in-furnace inspection is clamped by the in-furnace inspection apparatus.

FIG. 7 is an explanatory diagram of the out-of-furnace position coordinate setting. By connecting the out-of-core inspection device to the CRD housing in which the defect is detected, the reference coordinate axis can be set in the out-of-core inspection device in the same procedure as that for setting the reference coordinate axis during the in-core inspection. The same reference coordinate axis can be provided outside the furnace. Based on this reference coordinate axis, the outside inspection apparatus is accessed as needed so as to detect the part having the defect position coordinates (r ₁ , z ₁ , θ ₁ ) already identified by in-furnace inspection. Conduct an ultrasonic flaw inspection of the part.

FIG. 8 shows an example of measurement by the out-of-core inspection apparatus according to the first embodiment. The trolley 15 of the out-of-furnace inspection apparatus is seated, the tube center axis direction of the defective CRD housing is z _0, and the adjacent CRD housing of the out-of-furnace inspection apparatus trolley 15 is seated from the tube center of the defective CRD housing. up tube center and r _0, from the tube center of the CRD housing having a defect the distance to the ultrasonic sensor 17 and r _2, from r ₀ direction about the tube center of the CRD housing having a defect to the ultrasonic sensor 17 The rotation angle is θ _2, and the distance from the place where the cart 15 of the out-of-furnace inspection device is seated to the ultrasonic sensor 17 in the tube central axis direction of the CRD housing is measured as z ₂ . These positions are measured by a normal measuring device as in the case of controlling the position of a robot arm or the like. The measured position information is recorded in the database of the in-furnace inspection device. Ultrasonic flaw detection from the position coordinates (r ₂ , z ₂ , θ ₂ ) of the ultrasonic sensor 17 of the out-of-furnace inspection apparatus in the direction of the defect position coordinates (r ₁ , z ₁ , θ ₁ ) already identified by the in-furnace inspection Conduct an inspection.

FIG. 9 is an explanatory diagram of setting the position coordinates inside and outside the furnace. When the three-dimensional coordinate origin is shared between the inside and outside of the furnace, the intersection of the CRD housing tube center axis 12 and the CRD housing upper surface 13 where the in-furnace inspection apparatus of FIG. Is z ₁ , the axial thickness of the RPV is z _t, and z ₂ is the distance from the ultrasonic sensor 17 of the out-of-furnace inspection device to the running surface position of the carriage 15 of the out-of-furnace inspection device. The Z coordinate of the running surface position of the cart 15 can be set as the distance Z from the origin in the furnace. In this way, using the structure penetrating the RPV lower mirror part (furnace bottom), the three-dimensional coordinate origin is shared between inside and outside the furnace.

  In addition, the alignment based on the reference coordinate axis described above uses a structure penetrating the RPV lower mirror (furnace bottom) and shares the three-dimensional coordinate origin both inside and outside the furnace. Of these, the origin of the two-dimensional coordinates may be shared inside and outside the furnace. That is, the origin of the Z axis is not shared as in the position coordinates of FIG. 9, and the Z axis origin can be provided separately as in the in-furnace position information of FIG. 5 and the out-of-furnace position information of FIG.

  As an example of matching the measurement results of the same defect size or range for different inspection results from inside and outside the furnace, as described above, the measurement device is aligned with the position of the same CRD housing inside and outside the furnace. This is done by aligning the position of the defect by measuring the position. Moreover, as another example, in order to evaluate defects from inspection images from inside and outside the furnace, a technique for evaluating by performing position display based on the same coordinates for position information of each defect in the inspection images from inside and outside the furnace The person can evaluate more accurately from both images. As another example, in order to evaluate defects from inspection images from inside and outside the furnace, coordinate axes may be displayed for each inspection image from inside and outside the furnace in a range including the same defect. Like these, matching the measurement results of the same defect size or range in two directions from the inside and outside of the furnace is the same for different inspection results from inside and outside the furnace in order to facilitate defect evaluation. This is done by matching the position of the inspection result including the defect.

  In addition, the alignment based on the reference coordinate axis described above shares the plane coordinates (r, θ) using a structure penetrating the RPV lower mirror (furnace bottom), but does not share it, and the interior of the furnace of FIG. The position information and the out-of-furnace position information of FIG. 7 may be provided, and the relative position between the in-furnace position information and the out-of-furnace position information may be interpolated with reference to the design information of the bottom of the furnace. In this way, it is possible to obtain defect position information inside and outside the furnace and match the measurement results without sharing the origin of coordinates. In this case, even if the inspection device cannot be connected to the same CRD housing inside and outside the furnace, the ultrasonic flaw inspection can be performed for the same defect. However, when the inspection device is connected to the same CRD housing, the difference between the RPV actual machine and the design information is less, and the measurement can be performed with higher accuracy.

  As described above, in the inspection of the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, non-destructive inspection is performed from two directions from the inside of the RPV (inside the reactor) and from the outside of the RPV (outside the reactor). The inspection accuracy of narrow and complex welds can be improved by the inspection method of measuring the size or range of the same defect and matching the measurement results of the two methods. Moreover, since each inspection result is matched, a more detailed evaluation of a defect can be performed and inspection accuracy can be improved. As described above, after performing nondestructive inspection from inside the furnace for defects generated in RPV or an internal structure attached to RPV, and measuring the size and range of the defects, the nondestructive inspection is performed. Based on the obtained defect position information, nondestructive inspection is performed from the outside of the furnace, the size and range of the same defect are measured, and the defect position is first determined by in-furnace inspection by the inspection method that matches the measurement results of the two methods. By measuring, since the degree of freedom of the installation position of the inspection apparatus is higher than in the furnace, it is easy to match the measurement results, and an image with a high accuracy can be obtained for the image that matches the defect images inside and outside the furnace.

  Conventionally, when inspection is performed without using the defect position coordinates specified by in-furnace inspection, an ultrasonic sensor is brought into contact with the outer surface of the RPV, scanning is performed while transmitting ultrasonic waves, and a reflection echo is confirmed to confirm the defect. I was seeking a position.

  However, in the first embodiment, the result of the in-furnace inspection is used to access the out-of-furnace inspection apparatus, so that the work time in the out-of-furnace inspection can be shortened and the work efficiency of the entire inspection can be improved. . In addition, by measuring the defect position by in-furnace inspection first, the degree of freedom of the installation position of the inspection device is higher than in the furnace, so it is easy to complement the range inspected from the outside, both obtained Defects can be accurately evaluated from images.

  As described above, using a structure penetrating the RPV lower mirror part (furnace bottom), the three-dimensional coordinate origin is shared between the inside and outside of the furnace, or the two-dimensional coordinate origin among the three-dimensional coordinate origins. By sharing the inside and outside of the furnace, the in-core flaw detection result and the out-of-furnace flaw detection result are expressed on the same coordinate axis, so that the two flaw detection results can be easily combined and evaluated.

  As described above, in the inspection apparatus for inspecting the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, the inspection unit for performing nondestructive inspection from the inside of the RPV (inside the furnace), and the outside of the RPV (outside of the furnace) ) From the RPV inside (furnace) and from the RPV outside (outside of the furnace) the recording unit that receives and records the data from the non-destructive inspection, and from the two directions Display section for displaying both non-destructive inspection data, defect position information obtained by measuring the size or range of the defect by performing non-destructive inspection from inside the furnace, and non-destructive information from outside the furnace The inspection device with a control device that displays the measurement result of the defect position information obtained by measuring the size or range of the same defect by performing destructive inspection on the display unit, the inspection accuracy of a narrow and complex shape welded portion To improve It can be. Moreover, since each inspection result is matched, a more detailed evaluation of a defect can be performed and inspection accuracy can be improved.

  As described above, the relative positional relationship between adjacent CRD housings is measured (the clamp of the CRD housing by the positioning plate 8 or the guide plate 18), and the position from one of the CRD housings to the measurement object is measured (the arm unit). 6, measurement and measurement based on the position of the CRD housing by the position measurement method for measuring the position of the measurement object of the internal structure attached to the RPV or RPV by moving the arm part 16 to the defect position) Can be obtained easily and accurately.

  As described above, the positioning device (positioning plate 8, guide plate 18) that measures the relative positional relationship between adjacent CRD housings, and the arms (6, 16) that measure the position from one of the CRD housings to the measurement object. The position of the measurement object on the basis of the position of the CRD housing by the position measurement device (ultrasonic inspection device main body 5, carriage 15) that measures the position of the measurement object of the internal structure attached to the RPV or the RPV having Can be obtained easily and accurately. In order to easily and accurately obtain the position of the measurement object, the above-described nondestructive inspection apparatus inside and outside the furnace is not necessarily required.

  In Example 2, first, a non-destructive inspection from the outside of the furnace is performed by an ultrasonic inspection outside the furnace, and a defect is detected and a dimension is measured. Next, ultrasonic nondestructive inspection is performed from the inside of the furnace based on the defect position coordinates obtained by the in-furnace inspection. Finally, the defect shape is evaluated by matching both inspection results. Here, ultrasonic inspection (UT) is adopted in the nondestructive inspection in the furnace, but only one method among visual inspection (VT), overcurrent inspection (ECT), and ultrasonic inspection (UT), Either a combination of two methods or a combination of three methods may be applied.

The configuration of the out-of-core ultrasonic apparatus used in the out-of-core inspection is the same as that of the out-of-core ultrasonic apparatus of FIG. 6 of the first embodiment, and the process of measuring the defect is also the same as that of the first embodiment using the clamped CRD housing. Similarly to 8, the defect position coordinates (r ₁ , z ₁ , θ ₁ ) are specified. At this time, the defect position coordinates (r ₁ , z ₁ , θ ₁ ) are obtained as a result of performing ultrasonic flaw inspection with the position coordinates (r ₂ , z ₂ , θ ₂ ) of the ultrasonic sensor 17 of the out-of-core inspection apparatus. It is specified based on the position information of the defect. Next, based on the defect position coordinates (r ₁ , z ₁ , θ ₁ ), ultrasonic flaw inspection is performed from the inner surface side of the RPV. The configuration of the in-furnace ultrasonic device used here is the same as that of the in-furnace ultrasonic device of FIG.

In the second embodiment, since the defect position coordinates (r ₁ , z ₁ , θ ₁ ) are specified by the out-of-furnace inspection, the inside of the furnace is based on the defect position coordinates (r ₁ , z ₁ , θ ₁ ). The inspection device is accessed and ultrasonic flaw detection is performed from inside the furnace.

First, the in-furnace inspection apparatus is seated on the upper surface of the CRD housing in which the defect is detected, and the same CRD housing as the two CRD housings clamped when the reference coordinate axis is provided in the out-of-furnace inspection is clamped by the in-furnace inspection apparatus. As a result, the reference coordinate axis can be set in the in-furnace inspection apparatus in the same procedure as the procedure for setting the reference coordinate axis during the out-of-furnace inspection, and the same reference coordinate axis can be provided outside the furnace and in the furnace. Based on this reference coordinate axis, the in-furnace inspection apparatus is appropriately accessed so as to detect the part that becomes the defect position coordinates (r ₁ , z ₁ , θ ₁ ) already identified by the in-furnace inspection, Conduct an ultrasonic flaw inspection of the part.

  In the second embodiment, the result of the out-of-furnace inspection is used to access the in-furnace inspection apparatus. Therefore, the work time in the in-furnace inspection can be shortened, and the work efficiency of the entire inspection can be improved. Furthermore, since the in-core flaw detection result and the in-core flaw detection result are represented on the same coordinate axis as in the first embodiment, the two flaw detection results can be easily combined and evaluated.

  In Example 2 mentioned above, since the defect position is first measured by the outside inspection, the schedule of the in-reactor inspection which is narrow and has a low degree of freedom in the installation position of the inspection apparatus can be examined in advance. There is also an effect that the working time can be shortened. In addition, the inspection outside the furnace can be performed first while other work such as removal of the internal structure of the furnace is being performed, so it is possible to reduce the inspection time for both the inspection inside and outside the furnace. .

  As described above, in the inspection of the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, non-destructive inspection is performed from two directions from the inside of the RPV (inside the reactor) and from the outside of the RPV (outside the reactor). The inspection accuracy of narrow and complex welds can be improved by the inspection method of measuring the size or range of the same defect and matching the measurement results of the two methods. Moreover, since each inspection result is matched, a more detailed evaluation of a defect can be performed and inspection accuracy can be improved.

  As described above, after performing nondestructive inspection from the outside of the furnace for defects generated in RPV or internal structures attached to RPV, and measuring the size and range of the defects, the nondestructive inspection is performed. Based on the obtained defect position information, nondestructive inspection is performed from the inside of the furnace, the size or range of the same defect is measured, and the inspection method for matching the measurement results of the two methods is used to determine the defect obtained by the outside inspection. By performing inspection from the furnace based on the position coordinates, it is possible to reduce the work time for defect identification. In addition, by measuring the defect position first by out-of-furnace inspection, it is possible to examine in-furnace inspection schedules that are narrow and have a low degree of freedom in the installation position of inspection equipment, so the work time for in-furnace inspection is shortened. There is also an effect that it is possible to do. In addition, the inspection outside the furnace can be performed first while other work such as removal of the internal structure of the furnace is being performed, so it is possible to reduce the inspection time for both the inspection inside and outside the furnace. .

  As described above, using a structure penetrating the RPV lower mirror part (furnace bottom), the three-dimensional coordinate origin is shared between the inside and outside of the furnace, or the two-dimensional coordinate origin among the three-dimensional coordinate origins. By sharing the inside and outside of the furnace, the in-core flaw detection result and the out-of-furnace flaw detection result are expressed on the same coordinate axis, so that the two flaw detection results can be easily combined and evaluated.

  As described above, in the inspection apparatus for inspecting the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, the inspection unit for performing nondestructive inspection from the inside of the RPV (inside the furnace), and the outside of the RPV (outside of the furnace) ) From the RPV inside (furnace) and from the RPV outside (outside of the furnace) the recording unit that receives and records the data from the non-destructive inspection, and from the two directions Display section for displaying both non-destructive inspection data, defect position information obtained by measuring the size or range of the defect by performing non-destructive inspection from inside the furnace, and non-destructive information from outside the furnace The inspection device with a control device that displays the measurement result of the defect position information obtained by measuring the size or range of the same defect by performing destructive inspection on the display unit, the inspection accuracy of a narrow and complex shape welded portion To improve It can be. Moreover, since each inspection result is matched, a more detailed evaluation of a defect can be performed and inspection accuracy can be improved.

  As described above, the relative positional relationship between adjacent CRD housings is measured (the clamp of the CRD housing by the positioning plate 8 or the guide plate 18), and the position from one of the CRD housings to the measurement object is measured (the arm unit). 6, measurement and measurement based on the position of the CRD housing by the position measurement method for measuring the position of the measurement object of the internal structure attached to the RPV or RPV by moving the arm part 16 to the defect position) Can be obtained easily and accurately.

  As described above, the positioning device (positioning plate 8, guide plate 18) that measures the relative positional relationship between adjacent CRD housings, and the arms (6, 16) that measure the position from one of the CRD housings to the measurement object. The position of the measurement object on the basis of the position of the CRD housing by the position measurement device (ultrasonic inspection device main body 5, carriage 15) that measures the position of the measurement object of the internal structure attached to the RPV or the RPV having Can be obtained easily and accurately. In order to easily and accurately obtain the position of the measurement object, the above-described nondestructive inspection apparatus inside and outside the furnace is not necessarily required.

  In each of the above-described embodiments, either the in-furnace inspection or the out-of-furnace inspection is performed first and the other is performed later, but they may be performed simultaneously. However, the inspection that is performed at the same time when the position of the defect is not known in the furnace inside and outside the furnace, the defect position is not known, so that the work efficiency is lowered. Can do. Further, since the non-destructive inspection is performed from two directions from the inside of the RPV (inside the furnace) and from the outside of the RPV (outside of the furnace), the inspection accuracy of the narrow and complicated welded portion can be improved.

  In each of the above-described embodiments, the position measurement is performed using the arm unit 6, the arm unit 16, the positioning plate 8, the guide plate 18, and the like, but other position measurement devices may be used. For example, the position can also be measured by providing an ultrasonic transmitter attached to the container wall as in Patent Document 3 and an ultrasonic receiver attached to the inspection unit and causing the control unit to perform position determination.

1 Reactor pressure vessel (RPV)
2 Control rod drive guide tube (CRD housing)
3 CRD stub 4 CRD stub welded portion 5 Ultrasonic inspection apparatus main body 6, 16 Arm portion 7, 17 Ultrasonic sensor 8 Positioning plate 9 Guide pin 10 Pressing plate 11, 18 Guide plate 12 Pipe center shaft 13 Housing upper surface 14 Heat retaining material 15 Trolley

Claims (8)

  In the inspection of the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, nondestructive inspection is performed from two directions from the inside of the RPV (inside the reactor) and from the outside of the RPV (outside of the reactor). Or the inspection method which measures a range and matches the measurement result by said 2 methods.   The nondestructive inspection according to claim 1, wherein a nondestructive inspection is first performed from inside the furnace for defects generated in RPV or an internal structure incidental to the RPV, and the size and range of the defects are measured. Inspection method that carries out nondestructive inspection from outside the furnace based on the defect position information obtained by.   The nondestructive inspection according to claim 1, wherein nondestructive inspection is first performed from outside the furnace for defects generated in RPV or an internal structure attached to RPV, and the size and range of the defects are measured. Inspection method to perform nondestructive inspection from inside the furnace based on the defect position information obtained by 4. The inspection method according to claim 2, wherein a structure passing through an RPV lower mirror part (furnace bottom) is used, and the origin of a two-dimensional coordinate among the three-dimensional coordinate origins is set in a furnace. Inspection method characterized by sharing inside and outside the furnace. In the inspection method according to any one of claims 2 or claim 3, using the structure that penetrates RPV under the mirror unit (furnace bottom), share a coordinate origin of the three-dimensional in the furnace and the furnace outer Inspection method characterized by that.   In the inspection equipment that inspects the reactor pressure vessel (hereinafter referred to as RPV) or the internal structure attached to the RPV, the inspection part that performs nondestructive inspection from the inside of the RPV (inside the reactor) and the nondestructive inspection from the outside of the RPV (outside the reactor) An inspection unit for performing the non-destructive inspection from two directions from the inside of the RPV (inside the furnace) and the outside of the RPV (outside of the furnace), and a non-destructive inspection from the two directions In addition, a display unit that displays both data, defect position information obtained by measuring the size or range of the defect by performing nondestructive inspection from inside the furnace, and nondestructive inspection from outside the furnace The inspection apparatus which has the control apparatus which displays the measurement result of the defect position information which measured the dimension or range of the same defect on the said display part.   2. The position of the measurement object of the internal structure attached to RPV or RPV by measuring the relative positional relationship between adjacent CRD housings and measuring the position from one of the CRD housings to the measurement object. An inspection method characterized by measuring   7. The measurement of an internal structure attached to an RPV or RPV having a positioning device for measuring a relative positional relationship between adjacent CRD housings and an arm for measuring a position from one of the CRD housings to a measurement object. An inspection apparatus having a position measuring device for measuring the position of an object.

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