JP2010085141A - Method and device for measuring center of in-pile structure in reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability in the measurement of the center of an in-pile structure in a nuclear power plant. <P>SOLUTION: In a method for measuring the center of an in-pile structure in a core to measure an installed center of the in-pile structure as an inspection or replacement of the in-pile structure in the nuclear power plant, a target is mounted on a reference in-pile structure for the measurement of the center, a plumb bob center measurement device is mounted on the in-pile structure where its center should be measured, and the work to move the plumb bob center measurement device from the initial position of a plumb end to the center position of the target and to align it is verified by an underwater camera to measure the center of the in-pile structure by the travel of an XY table hanging a plumb bob wire of the device. This improves the reliability in the measurement of the center. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a core in-core structure and a core in-core structure to be core-measured when performing core measurement of the core in the reactor pressure vessel during the periodic inspection performed during the operation period of the nuclear power plant. The present invention relates to a lead measuring method and a lead measuring apparatus for measuring the amount of misalignment of the lead.

  As an installation core measurement method for the reactor internal structure in a nuclear power plant, there are an optical method using an alignment telescope and a method using a core measurement device disclosed in Japanese Patent Application Laid-Open No. 2002-39735.

  In the method disclosed in Japanese Patent Laid-Open No. 2002-39735, the distance between the first position and the second position that are separated from each other is known, and the distance between the first position and the second position is linear. It is a method of measuring the amount of misalignment between the first and second positions by measuring the amount of inclination of the formed reference bar.

JP 2002-39735 A

  The optical method using the alignment telescope in the prior art has been mainly implemented in the construction work (before the service period) of the nuclear power plant.

  However, when measuring the core of the in-reactor structure during the operation period of the nuclear power plant, the reactor pressure vessel is filled with water to reduce the exposure dose of workers, and the alignment scope (in air) and water Refraction occurs at the boundary of the core and accurate core measurement is not possible.

  On the other hand, as shown in Japanese Patent Laid-Open No. 2002-39735, the first and second are measured by measuring the amount of inclination of a linearly formed reference bar installed between the first and second positions that are separated from each other. In the method of measuring the misalignment amount at the position, it is necessary that the length of the reference rod is not less than the distance between the first and second positions. For example, when measuring the amount of misalignment of the core support plate, the first position is the core support plate hole and the second position is the CRD housing hole. The length of the apparatus becomes a large one of 4 m or more, and the storage location is limited. In addition, it is necessary to perform a precision check calibration test before carrying in the reactor building on the operating floor of the reactor building using a large test stand.

  In addition, since the vicinity of the core support plate is a high-dose site, the electric circuit in the inclinometer may malfunction or be damaged by radiation. If the inclinometer malfunctions due to radiation, and the core measurement value is calculated based on the malfunction, there is a problem that the displayed core measurement value cannot be verified.

  An object of the present invention is to improve reliability with respect to core measurement of a reactor internal structure of a nuclear power plant.

  A down-swing method is employed in a core measurement method for a reactor internal structure that performs installation core measurement of the reactor internal structure as an in-furnace structure inspection or replacement of the reactor internal structure of a nuclear power plant.

  ADVANTAGE OF THE INVENTION According to this invention, reliability can be improved regarding the core measurement of the reactor internal structure of a nuclear power plant.

  This is a simple method to check the amount of misalignment between the tip of the lower swing and the target with an underwater camera when measuring the core of the reactor internal structure during the operation period of the nuclear power plant. Since the vertical direction is always shown without being affected by a high radiation dose, the trouble of adjusting the measuring device is saved, and the core measurement value is highly reliable without requiring skill in measurement.

  In addition, it is easy to check the amount of misalignment indicated by the tip of the swing down to the target on the TV monitor via the underwater camera and measure the center with the amount of movement of the XY table.

  In addition, the amount of misalignment can be discriminated because the tip of the downward swing and the target are remotely visually confirmed by the underwater camera from close distances in two perpendicular directions.

  Also, when installing the swing-down type core measuring device in the furnace structure hole, the centering fixing mechanism is remotely operated so that the position of the swing-down wire becomes the center position of the core structure hole for core measurement. A swing-down core measuring device can be fixed.

  In addition, the downward swing type core measuring device uses the remote automatic XY drive mechanism to remotely move the plane position (XY direction) of the downward swing wire to the target center position or any position, and calculates the amount of misalignment from the amount of movement. Since it can be processed and displayed, the lead measuring operation can be easily performed.

  In addition, the downward swing type core measuring device can change the downward swing wire to an arbitrary length by the remote automatic wire length adjustment mechanism, so that the distance between the installation reference and the in-furnace structure to be measured is different. It is highly versatile because it can be used for core measurement in other plants with different in-furnace structures and installation dimensions.

  Also, by keeping the length of the swing-down wire to the minimum necessary when storing the device and during the accuracy check calibration test, it is not necessary to secure a large storage area, and the calibration test frame structure and the configuration test work can be simplified.

  Further, the downward swing type core measuring device is not affected by the prevention of damage of the downward swing wire and the flow of reactor water by passing the downward swing wire through the inner diameter of the split pipe.

  In addition, when measuring the installation core of the reactor internal structure during the operation period of the nuclear power plant, the reactor pressure vessel is full and the purification reactor water connected to the reactor pressure vessel is Although it is flowing, since the swinging wire passes through the inside of the split pipe, the wire does not swing due to the reactor water flow, and the tip of the swinging swing can stably point on the target.

  In addition, the downward swing type core measuring device is provided with a downward swing fixing mechanism (hereinafter referred to as a shutter) at the lowermost end portion of the split pipe so that the downward swing wire can be used during installation and removal work in the nuclear reactor. It is possible to avoid breakage of the camera and monitor the underwater camera to put it in and out of the shutter.

  By adjusting the length of the swinging-pick core measuring device except for the bottom end of the split-type pipe to a short length and using the remote automatic wire length adjustment mechanism to minimize the length of the swinging wire, the alignment fixing mechanism and remote Adjustment and operation check of the automatic XY drive mechanism and swing-down shutter are made possible by a simple adjustment stand.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a state in which core measurement of a reactor internal structure is being performed by the core measurement device according to the present invention.

  FIG. 1 shows a case where core measurement of the core support plate 3 is performed based on the control rod drive mechanism housing (hereinafter referred to as CRD housing) hole 2 in the reactor pressure vessel 1 in the in-service inspection at the nuclear power plant. An applied example is shown.

  In order to perform core measurement in the reactor during the service period, after opening the reactor pressure vessel top lid (not shown), the reactor well 4 is filled with water, a steam dryer, brackish water separator, fuel, Work from the work cart or refueling cart 6 on the reactor building operating floor 5 (hereinafter referred to as “operoflo”) with the control rod, control rod guide tube, and fuel support fittings (all not shown) removed remotely. An operator remotely installs the target 7 in the CRD housing hole 2 using a rope and a hook.

  Next, a swing-down core measuring device 9 (hereinafter abbreviated as core measuring device 9) is remotely suspended in the reactor by the work truck or the crane 8 of the refueling carriage 6, and the target 7 is installed. It is installed in the core support plate hole 3-1 immediately above the CRD housing hole 2.

  A cable 10 and an air hose 10 are connected to the core measuring device 9, and electric power and compressed air necessary for the function of the core measuring device 9 are supplied through the cable 10 and the air hose 10.

  The cable 10 and the air hose 10 connected to the lead measuring device 9 are connected to a remote operation panel 11 installed on the operation floor 5.

  FIG. 2 is a diagram showing details of the core measuring device 9 and the target 7 of FIG.

  The lead measuring device 9 includes a centering fixing mechanism 12, a remote automatic XY drive mechanism 13 (hereinafter abbreviated as an XY table 13), a downward swing wire 14, a remote automatic wire length adjustment mechanism 15 (hereinafter referred to as a wire length adjustment mechanism 15). For short). A split pipe 16 is attached to the lead measuring device 9.

  FIG. 3 is an explanatory diagram of the alignment fixing mechanism 12 of the core measuring device 9.

  The centering fixing mechanism 12 aligns the planar position of the core measuring device 9 so that the position of the downward swing wire 14 of the core measuring device 9 is the center position of the core supporting plate hole 3-1, so that the core supporting plate hole 3 has an inner diameter. It is to be fixed.

  When the adjusting bolt 17 is remotely rotated by an operation pole (not shown), the three sprockets 19 linked to the chain 18 rotate by the same amount. The three eccentric rings 21 are rotated through the pins 20 by the rotation of the sprockets 19. The pin 20 is attached with an eccentric amount 22 from the center of the eccentric ring 21. When the eccentric ring 21 rotates, a protruding amount 23 is generated, and is fixed at the same time as the three eccentric rings 21 are aligned with respect to the inner diameter of the core support plate hole 3-1. At this time, the protruding amount 23 of the three eccentric rings 21 is adjusted to be the same amount. The rotation of the adjusting bolt 17 performs torque management.

  FIG. 4 is an explanatory diagram of the XY table 13 of the lead measuring device 9.

  The XY table 13 is used to remotely move the planar position (XY direction) of the swing wire 14 to an arbitrary position.

  The XY table 13 is divided into an X table 24 and a Y table 25, and can run on an X direction rail 26 and a Y direction rail 27, respectively.

  A holder 28 through which the swing-down wire 14 is passed is fixed to the X table.

  The X table 24 and the Y table 25 are remotely moved to arbitrary positions on the X rail 26 and the Y rail 27 by rotating the ball screw 30 in the forward and reverse directions by the electric motor 29.

  At this time, rotation control of the electric motor 29 that rotates the ball screw 30 is performed by the remote operation panel 11 installed in the operation floor 5. The movement amount of the XY table 13 is displayed on the simple display 31 and the remote control panel 11.

  FIG. 5 is an explanatory diagram of the wire length adjusting mechanism 15 of the core measuring device main body 9.

  The rotating force of the electric motor 32 is converted into a drum rotating force by the worm 33 and the worm wheel 34 to rotate the drum 35. Since the electric motor 32 can rotate in the normal direction and the reverse direction, the downward swing wire 14 wound around the drum 35 can be remotely adjusted to an arbitrary length.

  At this time, the rotation control of the electric motor 32 that rotates the drum 35 is performed by the remote operation panel 11 installed in the operation floor 5. Note that the length of the swing-down wire 14 is displayed on the remote operation panel 11.

  FIG. 6 is an explanatory diagram of the split pipe 16 that can be attached to the lead measuring device 9.

  The split pipe 16 is used to prevent the swinging wire 14 from being damaged and to prevent the swinging wire 14 from swinging due to the flow in the reactor, from the core support plate hole 3-1 of the core measuring device to the target 7 on the CRD housing hole 2. It is attached in a state where the swinging wire 14 is passed between the parts (about 4 m).

  The split pipe 16 has a structure that can be split at the connecting portion 36. Further, a lower swing fixing shutter 38 is attached to the lower part of the divided pipe 16. The shutter 38 can be remotely opened and closed by driving the air cylinder 39. When the lead measuring device 9 is attached to and detached from the furnace, the shutter 38 is closed and the lowering swing 37 is fixed. As a result, even if the lower swing wire 14 is broken, the lower swing 37 is not dropped from the split pipe 16 and dropped into the nuclear reactor. When the lead measurement operation is performed, the shutter 38 is opened, and the distance between the target 7 and the tip of the downward swing 37 is adjusted to a distance that allows lead measurement by the wire length adjusting mechanism 15.

  Two core measuring underwater cameras 40 and one shutter 38 monitoring underwater camera 41 are attached to the lower part of the split pipe.

  The underwater camera 40 for core measurement is for photographing the tip of the downward swing 37 and the target from two directions at right angles, and the underwater camera 41 for monitoring the shutter 38 is for monitoring the downward swing shutter 38, and each image is set in the operation floor 5. The lead is measured by checking with the TV monitor of the remote control panel 11 that has been made.

  The above is an example in which the work procedure when performing the core measurement of the core support plate hole 3-1 based on the CRD housing hole 2 is described.

  When the core measurement of the upper lattice plate hole 3-2 is performed with reference to the core support plate hole 3-1, the core measurement device 9 is replaced with the alignment fixing mechanism 12 and the upper lattice plate hole 3-2. The hole 7 is replaced with the core support plate hole 3-1. The work procedure at this time is basically the same as the core measurement of the core support plate hole 3-1.

  Thus, it is characterized by being applicable to core measurement of other in-furnace structures including the jet pump 3-3.

  FIG. 7 shows an explanatory diagram of an adjustment / function confirmation test using the adjustment stand 41 of the lead measuring device 9 in the operation 5.

  Before the core measuring device 9 is inserted into the reactor pressure vessel 1 and the core measuring operation is performed, when the adjustment / function confirmation test of each part of the core measuring device is performed in the operating floor 5, the split pipe 16 is set to the minimum required length. It can be performed using the dedicated adjustment mount 42 in a state where it is removed from the connecting portion 36.

  Here, the adjustment / function confirmation test includes an operation confirmation of the alignment fixing mechanism 12, an operation confirmation of the XY table 13, an operation confirmation of the wire length adjustment mechanism 15, an operation confirmation of the shutter 38, and an underwater camera 40 image confirmation.

  Since the adjustment mount 42 can be replaced with the core support plate hole simulation 43 and the upper lattice plate hole simulation, it can be shared for adjustment and function test work of both core measuring devices.

  The target 7 is installed on an XY table 45 with a simple water tank 44.

  By filling the simple water tank 44 with water, the target 7, the tip of the downward swing 37, and the tip of the underwater camera 40 for core measurement can be made under the same underwater conditions as the actual work. In addition, the target 7 can be changed to an arbitrary position by the XY table 45, and it can be used for the operator's core measuring device operation training.

  As described above, according to the present embodiment, when measuring the centering of the in-furnace structure during the operation period of the nuclear power plant, it is easy to confirm the amount of misalignment between the tip of the swing-down and the target with the underwater camera. This is a method, and since the downward swing does not affect the temperature of the reactor water and is not affected by the high radiation dose, it always indicates the vertical direction, so that the core measurement value is highly reliable without requiring skill in core measurement.

  In addition, since the amount of misalignment indicated by the tip of the swinging down on the target is confirmed on the TV monitor via the underwater camera, and the lead is measured by the amount of movement of the XY table, the lead measuring operation is quick and easy.

  The split-type pipe of the down-swing type core measuring device is a detachable type, and since the length of the down-swing wire can be minimized by the remote automatic wire length adjustment mechanism, the device can be stored, adjusted, and function-checked easily. be able to.

Explanatory drawing which shows the state which is measuring the core of the reactor internal structure with the core measuring device by this invention. The figure which shows the detailed structure of a lead measuring apparatus. The figure which shows the detail of the alignment fixing mechanism of a core measuring device. The figure which shows the detail of XY table of a core measuring apparatus. The figure which shows the detail of the remote automatic wire length adjustment mechanism of a lead measuring device. The figure which shows the detail of the split-type pipe attached to a lead measuring device. Explanatory drawing at the time of adjusting and confirming a function of a lead measuring device by an adjustment stand.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reactor pressure vessel 2 CRD housing hole 3-1 Core support plate hole 3-2 Upper lattice plate hole 3-3 Jet pump 4 Reactor well 5 Operation floor 6 Work carriage or refueling carriage 7 Target 8 Crane 9 Core measuring device 10 Cable, hose 11 Remote operation panel 12 Alignment mechanism 13, 45 XY table 14 Lower swing wire 15 Remote automatic wire length adjustment mechanism 16 Split pipe 17 Adjustment bolt 18 Chain 19 Sprocket 20 Pin 21 Eccentric ring 22 Eccentric ring Amount 23 Projection amount 24 X table 25 Y table 26 X rail 27 Y rail 28 Holder 29 Electric motor 30 Ball screw 31 Simple display 32 Electric motor 33 Worm 34 Worm wheel
35 Drum 36 Joint 37 Lower swing 38 Shutter 39 Air cylinder 40 Underwater camera for core measurement 41 Underwater camera for shutter monitoring 42 Adjustment stand 43 Core support plate hole simulation 44 Simple water tank

Claims (10)

In the core measurement method of a reactor internal structure that performs installation core measurement of the reactor internal structure as an inspection of the nuclear reactor internal structure or replacement of the reactor internal structure,
Attach the target to the core measurement standard in the furnace structure, attach the down swing type core measuring device to the core structure that performs the core measurement, and move from the initial position of the downward swing tip to the target center position. A core measurement method for a reactor internal structure, wherein the core measurement of the reactor internal structure is performed based on the amount of movement of an XY table on which the swing wire is suspended, which is confirmed by an underwater camera.   When checking the in-core structure in the reactor pressure vessel during the operation period of the nuclear power plant or replacing the in-core structure, the in-core structure used as the standard for core measurement Remotely attach the target to the object and remotely attach the swing-type core measuring device to the in-furnace structure that performs core measurement and move it from the initial position of the swing-down tip to the target center position with a remote camera A core measuring method for a reactor internal structure, characterized in that the core measurement of the reactor internal structure is performed based on the amount of movement of the XY table hanging the swinging wire. In the core measuring device for the reactor internal structure that performs the installation core measurement of the internal structure of the nuclear power plant as the internal structure inspection or replacement of the internal structure of the nuclear power plant,
A standard for core measurement, comprising a target attached to the in-furnace structure, and a downward swing type core measuring device attached to the in-furnace structure for measuring the core, wherein the initial position of the tip of the downward swing A core measuring device for a reactor internal structure, comprising: an underwater camera capable of confirming an operation to move to a target center position from the target.   4. The lead measuring device according to claim 3, wherein the tip of the downward swing and the target position can be remotely visually confirmed by the underwater camera from two directions at right angles.   5. The lead measuring device according to claim 3, further comprising a centering fixing mechanism in which the position of the downward swing wire is the center position of the in-furnace structure.   The lead measuring device according to any one of claims 3 to 5, wherein a distance is obtained by remotely moving the planar position (XY direction) of the swing wire to a target center position or an arbitrary position by a remote automatic XY drive mechanism. A center measuring apparatus, wherein the center misalignment amount is calculated from the amount of movement and displayed.   The lead measuring device according to any one of claims 3 to 6, further comprising a remote automatic wire length adjusting mechanism capable of remotely changing arbitrarily the swinging wire length. Measuring device.   The core measuring device according to any one of claims 3 to 7, wherein the swinging wire is passed through the inner diameter of the split pipe, thereby preventing the swinging wire from being damaged and the swinging wire being affected by the reactor water flow. Core measuring device characterized by a structure that is not subject to damage.   The lead measuring device according to claim 7, further comprising a mechanism for collecting the swing-down swing and an underwater camera for monitoring the collecting state at the lowermost end portion of the split pipe.   The lead measuring device according to any one of claims 3 to 7, wherein the lead measuring device is a short lead measuring device from which the split-type pipe is removed. A lead measuring device characterized in that adjustment of the wire length adjusting mechanism is made possible by an adjusting stand.

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