JP2014106015A - Horizontal monitor device and method for main steam line plug device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a horizontal monitor device such that a tilt of a main steam line plug device at a water depth position exceeding 10 m can be visually monitored from above when the main steam line plug device is suspended in cooling water at the height of a main steam nozzle in a state where a reactor pressure vessel is filled with the cooling water.SOLUTION: A horizontal monitor device 20 includes: a scale plate 22 fixed to an upper surface of a main steam line plug device; and a rod-like pendulum device 24 which has an upper end 24a suspended above the device to swing and extended perpendicularly downward and also has a lower end located at the center O of the scale plate 22 with its own weight when the device is positioned horizontally. The device is suspended so that when the pendulum device 24 is viewed from perpendicularly above, the lower end (a tip of tip hardware) of the pendulum device 24 overlaps the center O of the scale plate 22, and the device is monitored to be held horizontally.

Description

  The present invention relates to a horizontal monitoring device and method for a main steam line plug device that monitors the main steam line plug device to keep it horizontal.

  The main steam (MS) line of the boiling water reactor (BWR) is composed of four main steam pipes that guide the steam generated in the reactor pressure vessel (RPV) to the turbine. Each main steam pipe is provided with a main steam flow controller and a relief safety valve in the main steam nozzle of the reactor pressure vessel, and a main steam isolation valve (MSIV) is provided before and after the penetration portion of the containment vessel. .

The main steam (MS) line is inspected (leak test, pressure test, etc.) for the relief safety valve, main steam isolation valve, etc. that constitute the main steam line in a periodic inspection conducted at a preset cycle (for example, one and a half years). , Functional tests, etc.).
In this periodic inspection, a main steam line plug device (MSLP) is used to close the main steam nozzle from the inside of the reactor pressure vessel.

  The main steam line plug device has four plugs for closing four main steam nozzles provided at the same height in the reactor pressure vessel from the inside, and has a function of pushing each plug into the main steam nozzle. Therefore, the four plugs of the main steam line plug device and the pushing mechanism thereof are located close to the inner surface of the reactor pressure vessel.

  The closing operation of the main steam nozzle by the main steam line plug device is performed in a state where the reactor pressure vessel is filled with cooling water (pure water). At this time, it is necessary to lift the main steam line plug device by a crane provided on the upper part of the reactor pressure vessel and to suspend the cooling water by the crane to the height of the main steam nozzle while maintaining the level.

  Therefore, a plurality of (for example, four) water depth sensors are attached to the outer periphery of the main steam line plug device, and the detected values (water depths) of the respective water depth sensors are monitored so that the main steam line plug device is kept horizontal. I was planning.

  Means for measuring the inclination relative to the horizontal is disclosed in, for example, Patent Documents 1 and 2.

Patent Document 1 is a method and apparatus for examining how much a boring hole is displaced with respect to a planned drilling line, and has a bubble level that is a measuring device for measuring an inclination with respect to the horizontal. It is.
Japanese Patent Application Laid-Open No. H10-228561 remotely transmits an accurate inclination angle with respect to the core to the operator by using an electronic level in an alignment apparatus for installing a control rod drive mechanism housing.

JP 2008-14893 A JP-A-2-264890

The inner diameter of the reactor pressure vessel is large (for example, 6 m or more), and the water depth at which the main steam line plug device (MSLP) is located is deep (for example, 10 m). Therefore, if the main steam line plug device tilts in the reactor pressure vessel when the main steam line plug device is lifted or lowered in the cooling water, the main steam line plug device may stick to the inner surface of the reactor pressure vessel. There is.
However, at the time of lifting and hanging at a depth of 10 m, only monitoring from above was possible, and it was difficult to detect inclination.

In order to avoid this stick, conventionally, as described above, monitoring is performed so that the detection values (water depths) of a plurality of (for example, four) water depth sensors coincide with each other to maintain the main steam line plug device horizontally. It was.
However, in the case of this means, since a long sensor cable of 10 m or more connecting the water depth sensor and the upper part of the reactor pressure vessel is handled at the same time, workability deteriorates, and the water depth sensor and the sensor cable are easily damaged by the water pressure in the water. There was a problem that the water depth detection accuracy was likely to deteriorate.

  The present invention has been developed to solve the above-described problems. That is, the object of the present invention is to suspend the main steam line plug device from the main steam line plug device to the height of the main steam nozzle in the state where the reactor pressure vessel is filled with the cooling water, at a main water depth position exceeding 10 m. An object of the present invention is to provide a horizontal monitoring device and method for a main steam line plug device that can visually monitor the inclination of the steam line plug device from above.

According to the present invention, a horizontal monitoring device for a main steam line plug device suspended by a hanger,
A scale plate fixed to the upper surface of the main steam line plug device;
When the upper end of the main steam line plug device is swingably suspended above the main steam line plug device and extends vertically downward, and the main steam line plug device is positioned horizontally, the lower end is located at the center of the scale plate with its own weight. A lowering device,
The main steam line plug device is kept horizontal by hanging the main steam line plug device so that the lower end of the swing device overlaps the center of the scale plate when the swing device is viewed from above. A horizontal monitoring device for the main steam line plug device is provided.

According to the embodiment of the present invention, the hanging tool and the main steam line plug device are configured such that when the main steam line plug device is positioned horizontally, the hanging object suspended by the hanging tool is vertically above the center of the scale plate. Connected to be located at
The swing-down device includes a spherical bearing in which a contact surface between an inner ring and an outer ring is a spherical surface and the outer ring is fixed to a lower portion of a suspended object, a bar member whose upper end is fixed to the inner ring of the spherical bearing and linearly extends downward, And a tip hardware fixed to the lower end of the member and having a pointed portion at the lower end.

Further, the upper surface of the scale plate is a spherical surface with a horizontal or central recess when the main steam line plug device is positioned horizontally.
A plurality of circular marks concentrically surrounding the center are displayed on the upper surface of the scale plate, and the radius of each circular mark is proportional to the inclination angle of the main steam line plug device.

Moreover, according to the present invention, there is provided a horizontal monitoring method for a main steam line plug device suspended by a hanging tool,
A scale plate fixed to the upper surface of the main steam line plug device;
When the upper end of the main steam line plug device is swingably suspended above the main steam line plug device and extends vertically downward, and the main steam line plug device is positioned horizontally, the lower end is located at the center of the scale plate with its own weight. A lowering device,
The main steam line plug device is kept horizontal by hanging the main steam line plug device so that the lower end of the swing device overlaps the center of the scale plate when the swing device is viewed from above. There is provided a method for horizontal monitoring of a main steam line plug device characterized by monitoring.

According to the apparatus and method of the present invention, the upper end of the swing-down device is suspended so as to be swingable above the main steam line plug device, and vertically extends downward. The lower end is always located under its own weight directly below the upper end.
The scale plate is fixed to the upper surface of the main steam line plug device, and the swing-down device is positioned so that the lower end is located at the center of the scale plate by its own weight when the main steam line plug device is positioned horizontally. Therefore, when the main steam line plug device is tilted off the horizontal, the lower end of the swing-down device is moved away from the center of the scale plate in the downward direction of the main steam line plug device by a distance proportional to the tilt angle. Therefore, the magnitude and direction of the inclination of the main steam line plug device can be visually confirmed by the distance and direction.

  Therefore, when the swinging device is viewed from above, the main steam line plug device is kept horizontal by suspending the main steam line plug device so that the lower end of the swinging device overlaps the center of the scale plate. Can be monitored.

Thus, when the cooling water is suspended to the height of the main steam nozzle in the state where the reactor pressure vessel is filled with the cooling water, the main steam line plug device at a water depth position exceeding 10 m. Can be monitored visually from above, and troubles (such as sticks) due to deterioration in workability, such as when using a water depth sensor, damage to the water depth sensor and sensor cable, and deterioration in water depth detection accuracy It can be avoided in advance.

It is a schematic diagram which shows the closing operation | work of the main steam nozzle by the main steam line plug apparatus. It is an AA arrow line view of FIG. It is a principal part enlarged view of FIG. It is a figure which isolate | separates and shows the main steam line plug apparatus of FIG. FIG. 4 is a partially enlarged view of FIG. 3. It is a schematic diagram of the horizontal monitoring apparatus by this invention. It is a figure which shows the use condition of the horizontal monitoring apparatus by this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a schematic diagram showing a closing operation of the main steam nozzle 2 by the main steam line plug device 10.

  In this figure, 1 is a reactor pressure vessel (RPV), 2 is a main steam nozzle, 3 is an upper water tank provided at the top of the reactor pressure vessel 1, and 4 is a ceiling provided at the top of the reactor pressure vessel 1. A crane 5 is a hanging tool suspended by the overhead crane 4, 6 is a connecting beam that connects the lifting tool 5 and the main steam line plug device 10, and 7 is a hanging object that is suspended by the lifting tool 5.

The top lid 1a of the reactor pressure vessel 1 has already been removed in this figure. Cooling water (pure water) is stored in the reactor pressure vessel 1 and the upper water tank 3, and the upper part of the upper water tank 3 is open.
Further, the main steam pipe, the main steam flow controller, the relief safety valve, the main steam isolation valve, and the like connected to the outside of the main steam nozzle 2 are not shown.

  The cooling water has no flow or vortex at the start of the closing operation, is at room temperature, and has a transparency that can be seen visually from the top to the height of the main steam nozzle 2 (water depth of about 10 m).

FIG. 2 is an AA arrow view of FIG.
In this example, four main steam nozzles 2 are provided, of which the main steam nozzles 2 </ b> A and 2 </ b> C and the main steam nozzles 2 </ b> B and 2 </ b> D are provided symmetrically with respect to the center of the reactor pressure vessel 1.

FIG. 3 is an enlarged view of the main part of FIG. 1, and FIG. 4 is a diagram showing the main steam line plug device 10 of FIG. 3 separately.
2 to 4, the main steam line plug device 10 includes a plug 12, a back pressure support ring 14, and an X beam 16.

  The plug 12 has a function of being inserted into the main steam nozzle 2 from the inside and sealing the main steam nozzle 2, and includes a pneumatic or water pressure seal and an O-ring. In this example, four plugs 12 are prepared, one for each of the four main steam nozzles 2 (2A, 2B, 2C, 2D).

The back pressure support ring 14 has a ring mount 14 a that extends in a ring shape along the inner surface of the reactor pressure vessel 1. The cross-sectional shape of the ring mount 14a is rectangular in this example. With this configuration, the fuel in the reactor pressure vessel 1 can be moved even during the periodical inspection even when the reactor pressure vessel 1 is attached.
The ring mount 14a of the back pressure support ring 14 is set on a bracket (not shown) provided in the reactor pressure vessel 1, and functions as a mount that supports the entire apparatus when the plug 12 is inserted and pulled out.

As shown in FIG. 4, the back pressure support ring 14 includes a plug support member 14b that can move horizontally outward from the outer peripheral surface of the ring mount 14a, and a plug pressing jack 14c that presses the plug support member 14b outward in the horizontal direction. It has.
The plug support member 14b and the plug pressing jack 14c are provided at positions facing the plugs 12 in total, one for each of the four plugs 12.
With this configuration, the back pressure support ring 14 is set at the height of the main steam nozzle 2 after the plug is attached, and the plug 12 is attached to the pressure on the main steam piping side during the main steam isolation valve (MSIV) leak test. It can be pressed from the inside of the furnace pressure vessel 1.

In FIG. 2, a plurality of guides 14d are further provided on the outer peripheral surface of the ring mount 14a. The guide 14d has a vertical groove that extends vertically and opens outward.
On the other hand, a plurality of vertically extending guide rods 1b are fixed to the inner surface of the reactor pressure vessel 1, and the circumferential position of the ring mount 14a is adjusted by fitting the guide rod 1b into the vertical groove of the guide 14d. The four plugs 12 are guided to maintain the corresponding positions of the main steam nozzles 2 in the circumferential direction.

  The X beam 16 is composed of a first horizontal beam 16a whose both ends are close to the main steam nozzles 2A and 2C and a second horizontal beam 16b whose both ends are close to the main steam nozzles 2B and 2D. Have. The heights of the first horizontal beam 16a and the second horizontal beam 16b are set to be the same.

  As shown in FIG. 4, the X beam 16 has a connecting jack 17 at the lower ends of both ends of the first horizontal beam 16a and the second horizontal beam 16b, and a plug push-in jack 18 at the upper ends of both ends.

The connecting jack 17 inserts or pulls out pins into the fitting holes provided on the inner surface of the ring mount 14a in a state where both ends of the first horizontal beam 16a and the second horizontal beam 16b are supported on the upper surface of the ring mount 14a. It is like that.
With this configuration, the X beam 16 can be integrated with the back pressure support ring 14 by inserting a pin into the fitting hole, and the X beam 16 can be removed from the back pressure support ring 14 by pulling the pin out of the fitting hole. Can be separated.

The plug push-in jack 18 pushes or pulls the plug 12 radially outward in a state where the X beam 16 is integrated with the back pressure support ring 14. Moreover, the attachment / detachment mechanism (not shown) with the plug 12 is also provided.
With this configuration, at a position where the plug 12 faces the main steam nozzle 2, the plug 12 can be pushed into the main steam nozzle 2 radially outward or pulled out from the main steam nozzle 2.

  In the above-described example, the plug 12, the back pressure support ring 14 and the X beam 16 constituting the main steam line plug device 10 are configured to be separable, but the present invention is not limited to this configuration, and the whole May be configured integrally.

FIG. 6 is a schematic diagram of a horizontal monitoring device 20 according to the present invention.
In this figure, a horizontal monitoring device 20 according to the present invention includes a scale plate 22 and a swing-down device 24.

The scale plate 22 is fixed to the center of the upper surface of the main steam line plug device 10 (specifically, the X beam 16), as shown in FIGS.
Moreover, when the main steam line plug apparatus 10 is located horizontally, the upper surface of the scale plate 22 is a spherical surface that is recessed horizontally or in the center. Further, a plurality of circular marks 22 a are displayed on the upper surface of the scale plate 22. Each circular mark 22a concentrically surrounds its center O and has a radius proportional to the inclination angle of the main steam line plug device 10. In this example, the four circular marks 22a are, for example, 1, 2, 3, 4 degrees from the inside. The inclination angle is shown. In addition, you may make it show the level difference between the both ends of the main steam line plug apparatus 10 or the X beam 16 instead of an inclination angle.

  The swinging device 24 is a rod-like member, and the upper end 24a is suspended so as to be swingable above the main steam line plug device 10 and extends vertically downward, so that the main steam line plug device 10 is positioned horizontally. The lower end 24b is positioned at the center O of the scale plate 22 by its own weight.

In FIG. 6, the swing-down device 24 has a spherical bearing 25a fixed to the lower part of the hanging object 7 on which the contact surface of the inner ring and the outer ring is spherical and the outer ring is suspended by the hanger 5, and an upper end on the inner ring of the spherical bearing 25a. Is fixed to the lower end of the bar member 25b and has a tip metal piece 25c having a pointed end at the lower end.
The bar member 25b is preferably a metal member having high bending rigidity, and is not deformed by resistance due to movement in the cooling water.

1 and 3, the main steam line plug device 10 (specifically, the X beam 16) is such that when the main steam line plug device 10 is positioned horizontally, the hanger 7 is perpendicular to the center O of the scale plate 22. They are connected by a plurality (at least three) of connecting beams 6 so as to be positioned above.
The connecting beam 6 is preferably a metal member having high bending rigidity, and the hanging object 7 is integrated with the X beam 16 through the connecting beam 6.

  Further, in this example, the hanger 7 and the main steam line plug device 10 are arranged such that the hanger 7 is positioned vertically above the center O of the scale plate 22 when the main steam line plug device 10 is positioned horizontally. Is set.

FIG. 7A is a diagram showing a usage state of the horizontal monitoring device 20 according to the present invention.
In this figure, the main steam line plug device 10 includes a plug 12, a back pressure support ring 14, and an X beam 16 that are integrally connected to each other. Shows a state in which is inclined.
The inclination of the main steam line plug device 10 is higher on the right side and lower on the left side in this example.
In this case, the center O of the scale plate 22 moves to the right in the figure with respect to the upper end 24a of the swinging device 24, but the lower end 24b of the swinging device 24 continues to be positioned directly below the upper end 24a due to its own weight.
That is, when the main steam line plug device 10 is tilted away from the horizontal, the lower end 24b of the swing-down device 24 is in the center of the scale plate 22 in the direction in which the main steam line plug device 10 is lowered by a distance proportional to the tilt angle. Since it leaves | separates from O, the magnitude | size and direction of the inclination of the main steam line plug apparatus 10 can be visually confirmed with the distance and direction.

FIG. 7B is a diagram showing another usage state of the horizontal monitoring device 20 according to the present invention.
In this figure, the plug 12 and the back pressure support ring 14 constituting the main steam line plug device 10 are left in the reactor pressure vessel 1 and set at the height of the main steam nozzle 2, so that the pressure on the main steam line side is set. In contrast, the plug 12 is pressed from the inside of the reactor pressure vessel 1. In this state, a leak test of the main steam isolation valve (MSIV) can be performed.
In this example, only the X beam 16 constituting the main steam line plug device 10 is suspended by the hanger 5, and the X beam 16 is tilted.
In this example, the inclination of the X beam 16 is higher on the right side and lower on the left side.
In this case, the center O of the scale plate 22 moves to the right in the figure with respect to the upper end 24a of the swinging device 24, but the lower end 24b of the swinging device 24 continues to be positioned directly below the upper end 24a due to its own weight.
That is, when the X beam 16 is tilted away from the horizontal, the lower end 24b of the swing-down device 24 is separated from the center O of the scale plate 22 in the downward direction of the X beam 16 by a distance proportional to the tilt angle. The magnitude and direction of the inclination of the main steam line plug device 10 can be visually confirmed by the distance and direction.

  Therefore, by using the horizontal monitoring device 20 described above, the main steam line plug device 10 so that the lower end 24b of the swinging device 24 overlaps the center O of the scale plate 22 when the swinging device 24 is viewed from vertically above. Can be monitored to keep the main steam line plug device 10 horizontal.

According to the above-described apparatus and method of the present invention, the upper end 24a of the swinging device 24 is suspended so as to be swingable above the main steam line plug device 10 (lower portion of the hanging object 7 suspended by the hanging tool 5), Since it extends vertically downward, the lower end 24b (tip metal piece 25c) is always located under its own weight under the upper end 24a unless it receives a strong water flow even in water.
The scale plate 22 is fixed to the upper surface of the main steam line plug device 10, and the swing-down device 24 has a lower end 24b at the center O of the scale plate 22 when the main steam line plug device 10 is positioned horizontally. Therefore, when the main steam line plug device 10 is tilted away from the horizontal, the swing-down device is lowered in the downward direction of the main steam line plug device 10 by a distance proportional to the tilt angle. Since the lower end 24b (tip metal piece 25c) of 24 is separated from the center O of the scale plate 22, the magnitude and direction of the inclination of the main steam line plug device 10 can be visually confirmed by the distance and direction.

  Therefore, when the swinging device 24 is viewed from above, the main steam line plug device 10 is suspended so that the lower end 24b (tip metal piece 25c) of the swinging device 24 overlaps the center O of the scale plate 22. The main steam line plug device 10 can be monitored to remain horizontal.

  As a result, when the cooling water is suspended from the main steam line plug device 10 to the height of the main steam nozzle 2 in the state where the reactor pressure vessel 1 is filled with the cooling water, the main steam at a depth of more than 10 m is obtained. The inclination of the line plug device 10 can be visually observed from above, and troubles associated with deterioration in workability such as when using a water depth sensor, damage to the water depth sensor and sensor cable, and deterioration in water depth detection accuracy ( For example, sticks) can be avoided in advance.

  In addition, this invention is not limited to embodiment mentioned above, Of course, a various change can be added in the range which does not deviate from the summary of this invention.

1 Reactor pressure vessel (RPV),
1a Top lid, 1b Guide rod,
2, 2A, 2B, 2C, 2D main steam nozzle,
3 Upper water tank, 4 Overhead crane, 5 Lifting tool,
6 articulated beams, 7 hanging objects,
10 main steam line plug devices, 12 plugs,
14 Back pressure support ring,
14a ring mount, 14b plug support member,
14c plug pressing jack, 14d guide,
16 X beam,
16a first horizontal beam, 16b second horizontal beam,
16c X mount, 17 connection jack,
18 Plug-in jack,
20 horizontal monitoring device,
22 Scale plate, 22a Circular mark,
24 swing-down device, 24a upper end, 24b lower end,
25a Spherical bearing, 25b Bar member, 25c Tip metal

Claims (4)

A horizontal monitoring device for a main steam line plug device suspended by a hanger,
A scale plate fixed to the upper surface of the main steam line plug device;
When the upper end of the main steam line plug device is swingably suspended above the main steam line plug device and extends vertically downward, and the main steam line plug device is positioned horizontally, the lower end is located at the center of the scale plate with its own weight. A lowering device,
The main steam line plug device is kept horizontal by hanging the main steam line plug device so that the lower end of the swing device overlaps the center of the scale plate when the swing device is viewed from above. A horizontal monitoring device for a main steam line plug device characterized by monitoring. The hanger and the main steam line plug device are connected such that when the main steam line plug device is positioned horizontally, the hanger suspended by the hanger is positioned vertically above the center of the scale plate. ,
The swing-down device includes a spherical bearing in which a contact surface between an inner ring and an outer ring is a spherical surface and the outer ring is fixed to a lower portion of a suspended object, a bar member whose upper end is fixed to the inner ring of the spherical bearing and linearly extends downward, The horizontal monitoring device for a main steam line plug device according to claim 1, further comprising: a tip metal fitting fixed to the lower end of the member and having a pointed portion at the lower end. When the main steam line plug device is positioned horizontally, the upper surface of the scale plate is a spherical surface with a horizontal or central recess.
2. The upper surface of the scale plate displays a plurality of circular marks concentrically surrounding the center thereof, and the radius of each circular mark is proportional to the inclination angle of the main steam line plug device. Horizontal monitoring device for main steam line plug device as described. A horizontal monitoring method for a main steam line plug device suspended by a lifting tool,
A scale plate fixed to the upper surface of the main steam line plug device;
When the upper end of the main steam line plug device is swingably suspended above the main steam line plug device and extends vertically downward, and the main steam line plug device is positioned horizontally, the lower end is located at the center of the scale plate with its own weight. A lowering device,
The main steam line plug device is kept horizontal by hanging the main steam line plug device so that the lower end of the swing device overlaps the center of the scale plate when the swing device is viewed from above. A horizontal monitoring method for a main steam line plug device, characterized by monitoring.

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