JPH0827385B2 - Traveling valve loading / unloading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of Invention] (Field of Industrial Application) The present invention relates to a reactor containment vessel (hereinafter referred to as PCV) of a nuclear power plant.
The main steam release safety valve (hereinafter referred to as SRV) or the main steam isolation valve (hereinafter referred to as MSIV) attached to the main steam pipe inside is disassembled and carried out of the PCV, or carried into the PCV to be assembled The present invention relates to a valve loading / unloading device.

(Prior Art) In a nuclear power plant, a reactor pressure vessel is housed in a PCV, and steam generated in the reactor pressure vessel is sent to a steam turbine via a main steam pipe, and this steam turbine is Driven to work. For this reason,
The main steam pipe extends from the reactor pressure vessel through the PCV and is connected to the steam turbine. In addition, to prevent the release of steam generated in the reactor pressure vessel to the outside of the PCV and the release of radioactive substances to the environment, MSI is installed in the main steam pipe inside the PCV.
V is provided. In addition, an SRV is installed in the main steam pipe in the PCV to prevent overpressure in the reactor pressure vessel.

The MSIV and SRV are regularly tested, disassembled, and inspected in consideration of the importance of their functions.

Usually, this overhaul and inspection is performed outside the PCV because it is necessary to prevent radiation exposure during work and improve workability and reliability.

At that time, the disassembly of MSIV and SRV and the transfer work to the outside of PCV are performed as follows.

 First, the disassembly and removal work of MSIV will be described.

To disassemble the MSIV, install the first chain block directly above the MSIV and install the second chain block with the main steam pipe inclined 45 ° in the axial direction of the MSIV. Next, the MSIV is attached to the upper mechanism of the first chain block and the second chain block MSIV, and both chain blocks work together.
Disassembly work.

The cooperative work of the first and second chain blocks is carried out by gradually winding both chain blocks and pulling out the upper mechanism of the MSIV from the main body of the MSIV.

After this withdrawal, the chain block attached to the monorail installed right above the MSIV is used to suspend the upper mechanism of the MSIV and move it out of the PCV along the monorail.

After the disassembling / inspecting work, the work of attaching the upper mechanism of the MSIV to the body of the MSIV is performed in the reverse order of the disassembling work of the upper mechanism of the MSIV described above.

 Next, the SRV disassembly and unloading work will be described.

The first chain block placed above the SRV is hung on the upper part of the SRV attached to the main steam pipe, and this is lifted. Then hang the second chain block on the bottom of the SRV,
Overturn this SRV. Next, suspend the SRV by the chain block attached to the monorail, carry it out of the PCV along the monorail and inspect it for disassembly. After overhaul work SRV
The mounting work is performed in the reverse order of the above-mentioned SRV disassembly and carry-out work.

(Problems to be Solved by the Invention) As described above, conventionally, the work of disassembling SRV or MSIV is performed by using a plurality of chain blocks and cooperating them. For discharging SRV or MSIV from the PCV, suspend the SRV or MSIV in the chain block attached to the monorail, and then use the PCV along the monorail.
It is carried out by moving it to the outside.

However, the disassembling work in which a plurality of chain blocks are cooperated and the suspending work of the monorail into the chain block requires a skill in a related operation and a large number of workers.

Furthermore, in general, there are four MSIVs in the PCV and six SRVs in the PCV.
-18 units are provided, but since the PCV is not so wide, there is a problem that if a temporary chain block is used for each valve, the workability is poor and the danger is high.

The present invention has been made in consideration of such points, and it is possible to easily disassemble / assemble and carry in / out the MSIV and SRV in the PCV, and it is possible to significantly improve reliability, safety and reliability. It is an object of the present invention to provide a traveling valve loading / unloading device in a PCV that can be used.

[Structure of Invention]

(Means for Solving Problems) The present invention relates to a wheel that engages with a plurality of monorails that horizontally extend between an upper portion of a main steam pipe valve in a reactor containment vessel and an upper portion of an equipment inlet / outlet port, A wheel support base to which the wheels are attached and corresponding to each of the monorails, a rail support body that is hung on each wheel support base orthogonal to the monorail and moves along the monorail, and a rail support body by the rail support body. A rail supported parallel to the rail, an electric chain block movably arranged along the rail, and a control device for controlling the rail support and a drive mechanism of the electric chain block, wherein the wheels are The wheel support frame, which is composed of drive wheels driven by a drive motor and driven wheels that move according to the movement of the rail support, is provided corresponding to the driven wheels, and The traveling valve loading / unloading device is characterized by being movable along a holding body.

(Operation) An electric chain block is placed above the valve for the main steam pipe by the control device, the valve is lifted by this electric chain block, and the valve is moved along the monorail to the equipment inlet / outlet port.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 illustrate one embodiment of the traveling valve loading / unloading device according to the present invention.

FIG. 2 is a schematic diagram of the inside of PCV4. In Figure 2, PC
A reactor pressure vessel 3 is installed in V, and one end of a main steam pipe 5 is connected to the reactor pressure vessel 3. The other end of the main steam pipe 5 penetrates the PCV 4 and is connected to a steam turbine (not shown) so that the steam generated in the reactor pressure vessel 3 can be sent to the steam turbine through the main steam pipe 5. ing.

The main steam pipe 5 in the PCV4 has a valve for the main steam pipe, for example, SR
V6 and MSIV7 are installed. Further, three monorails 20 are horizontally arranged between the upper side of the SRV6 and the upper side of an equipment carry-in / out port (not shown) of the PCV4. In addition, MSIV
Three monorails 21 are horizontally arranged between the upper part of 7 and the upper part of the PCV4 device loading / unloading port.

And these monorails, for example Monorail 20,
A traveling valve loading / unloading device 1 for SRV6 is installed, and a traveling valve loading / unloading device 2 for MSIV7 is installed on the monorail 21.

Next, the traveling valve loading / unloading devices 1 and 2 will be described in detail with reference to FIG.

The traveling valve loading / unloading devices 1 and 2 for SRV6 and MSIV7 have the same structure. As shown in Fig. 1, monorail
Three wheels 20 and 21 are arranged. Wheels 8a and 8b are movably mounted on the monorails 20 and 21, respectively, and central axes of the wheels 8a and 8b are attached to a wheel support base 9.

Further, a rail support 11 is hung on the wheel support base 9 orthogonally to the monorails 20 and 21, and therefore the rail support 11 is suspended.
Is movable along monorails 20 and 21. Further, of the wheels 8a and 8b, the wheel 8a at the center is a drive wheel 8a driven by the drive motor 10 provided on the rail support 11, and the wheels 8b on both sides move the rail support 11. It is a driven wheel 8b that moves according to.

Further, below the rail support 11 and below the rail support
The rail 13 is fixed in the same direction as the rail 11, and the rail 13 is also arranged orthogonal to the monorails 20 and 21.

Electric chain block 14 with hooks 15 on rails 13
Two are provided. Electric chain block 14 is a rail
It is possible to move along 13 and electric chain block
The movement of 14 along the rail 13 and the vertical movement of the hook 15 are
Both are driven by a drive mechanism (not shown) in the electric chain block 14. Further, stoppers 12 are fixed to both ends of the rail 13.

Of the three wheel support bases 9, the wheel support base 9 at the center is fixed to the rail support 11, but the wheel support bases 9 on both sides are movable along the rail support 11. . Therefore, the driven wheels 8b of the wheel support bases 9 on both sides are
Can easily follow the bending of monorails 20 and 21 and the difference in width. Further, as described above, since the wheels are composed of the drive wheels 8a and the driven wheels 8b,
When the traveling valve loading / unloading device 1 bends the curved portions of the monorails 20 and 21, the driven wheels 8b can absorb the difference in rotation amount between the wheel located outside the curve and the wheel located inside the curve. Therefore, unlike the case where all the wheels are composed of the drive wheels, it is not necessary to control the rotation amount of each drive wheel in accordance with the curvature of the curve, and the traveling valve loading / unloading device 1 can be installed in the monorails 20 and 21. When bending a curved portion, it can be easily bent even if the curvature of the curve is small.

The drive motor 10 for driving the wheels 8 and the drive mechanism in the electric chain block 14 are controlled by a control device (not shown) built in the rail support.

Next, the operation of this embodiment having such a configuration will be described with reference to FIGS.

First, referring to FIG. 3, the disassembling and unloading work of the SRV6 by the traveling valve loading / unloading device 1 will be described.

First, a hook 15 of one electric chain block 14 closest to the SRV6 is hooked on the SRV6 attached to the main steam pipe 5 and lifted up.

In this case, a biased load is applied to the rail support 11 and the rail 13, but this biased load is received by the three wheels 8a, 8b and the wheel support frame 9 mounted on the three monorails 20. To be held.

Next, the hook 15 of the other electric chain block 14 is SR
Hook it below V6 and turn SRV6 sideways. Then, the drive motor 10 is started with the SRV 6 suspended horizontally by the two electric chain blocks 14. As a result, the wheels 8 at the center are driven, and the traveling valve loading / unloading device 1 is moved to the monorail
SRV6 is carried to the equipment carry-in / out entrance.

Next, SRV6 is carried from the equipment loading / unloading port to the outside of PCV4 for disassembly and inspection work.

Next, the SRV6 which has been disassembled and inspected is carried in to the main steam pipe 5 in the PCV4 by the reverse operation to the above and assembled.

All the driving operations of these traveling valve loading / unloading devices 1 are automatically controlled by the control device.

Next, referring to FIG. 4, the disassembling and carrying out work of the MSIV7 by the traveling valve carrying in / out device 2 will be described.

First, diagonally above the MSIV7 attached to the main steam pipe 5 (4
Place one electric chain block 14 at 5 °). Next, hook the hook 15 of the electric chain block 14 on one side onto the upper part of the upper mechanism 7a of the MSIV7 to move the upper mechanism 7a of the MSIV7 to the MSI.
Pull up diagonally from the main body 7b of V7.

In this case, the hook 15 of the other electric chain block 14
It is hooked on the lower part of the upper mechanism 7a of MSIV7. By gradually lifting the lower part of the upper mechanism 7a of the MSIV7, the upper mechanism 7a can be smoothly pulled out from the main body 7b.

When hoisting the upper mechanism 7a, the offset load applied to the rail support 11 and the rail 13 is three monorails.
Three wheels 8a, 8b and a wheel support base 9 mounted on the 21
Will be taken care of by.

After completely pulling out the upper mechanism 7a of the MSIV7 from the main body 7b,
The drive motor 10 is started while the MSIV 7 is hung horizontally by the two electric chain blocks 14. As a result, the drive wheels 8a in the central portion are driven, the traveling type loading / unloading device 2 moves along the monorail 21, and the upper mechanism 7a is carried to the equipment loading / unloading port.

Next, the upper mechanism 7a is carried to the outside of the PCV4 from the equipment carry-in / out port, and disassembly and inspection work is performed. After the disassembly and inspection work is completed, the upper mechanism 7a is carried in and assembled to the main body 7b of the MSIV7 of the main steam pipe 5 in the PCV4 by the operation reverse to the above.

The operation of the traveling valve loading / unloading device 2 is also automatically controlled by the control device.

As described above, according to the present embodiment, in disassembling and carrying out the SRV6 and MSIV7, a large number of chain blocks are not required, and moreover, it is not necessary to suspend between the chain blocks, so that the work can be easily performed. It is possible to reduce the number of workers and improve work safety.

In the above-mentioned embodiment, the configuration of the two traveling type loading / unloading devices 1 and 2 for SRV6 and MSIV7 is shown.
One traveling type valve loading / unloading device for only one of the SIV7 may be used.

〔The invention's effect〕

According to the present invention, in disassembling / carrying out a valve for a main steam pipe, a large number of chain blocks are not required and a suspension between the chain blocks is not required. Therefore, it is possible to easily perform the work. It is possible to reduce the number of employees and work safety. Further, according to the present invention, the wheel includes a drive wheel driven by a drive motor and a driven wheel that moves according to the movement of the rail support, and the wheel support base provided with the driven wheel moves along the rail support. Therefore, when the traveling valve loading / unloading device bends a curved portion of the monorail, it can be easily bent even when the curvature of the curve is small. That is, according to the present invention, since the wheels are composed of driving wheels and driven wheels, when the traveling valve loading / unloading device bends a curved portion of the monorail, the wheels located outside the curve and the wheels located inside the curve. The driven wheel can absorb the difference in the amount of rotation. Therefore, it is not necessary to control the rotation amount of each drive wheel in accordance with the curvature of the curve as in the case where all the wheels are drive wheels. Further, according to the present invention, since the wheel support frame provided corresponding to the driven wheels is movable along the rail support, the change in mutual spacing between the plurality of monorails, especially the mutual spacing in the curved portion. Can be absorbed by the movement of the wheel support base. Therefore, the traveling valve loading / unloading device can smoothly travel along the monorail.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a traveling valve loading / unloading device according to the present invention, FIG. 2 is a layout view of the traveling valve loading / unloading device in a PCV, and FIG. 3 is an SRV disassembly / unloading work. Showing the fourth
The figure is a diagram showing the disassembly and unloading work of MSIV. 1, 2 ...... Traveling valve loading / unloading device, 3 …… Reactor pressure vessel,
4 …… PCV, 5 …… Main steam pipe, 6 …… SRV, 7 …… MSIV,
8 ... Wheels, 9 ... Wheel support frame, 10 ... Drive motor,
11 …… Rail support, 13 …… Rail, 14 …… Electric chain block, 20, 21 …… Monorail.

Claims (1)

[Claims] 1. A wheel engaging with a plurality of monorails horizontally extending between an upper portion of a main steam pipe valve and an upper portion of an equipment carry-in / out port in a reactor containment vessel, and each of the monorails to which the wheel is attached. A wheel support cradle corresponding to, a rail support that is hung perpendicular to the monorail on each wheel support cradle and moves along the monorail, and a rail supported by the rail support in parallel with the rail support, An electric chain block that is movably arranged along the rail, and a control device that controls a drive mechanism of the rail support and the electric chain block, the wheels being drive wheels driven by a drive motor. And a driven wheel that moves according to the movement of the rail support, and a wheel support base provided corresponding to the driven wheel is movable along the rail support. Traveling valve loading and unloading apparatus according to claim Rukoto.