JPS61119891A - Detachable device for expansion joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an expansion joint attachment/detachment device, and is mainly used for LPCI (Low Pres-s) in boiling water nuclear reactors.
ure (:, oolant l njecti
on 3 ystea Low-pressure water injection The present invention relates to a coupling used for connecting low-pressure water injection pipes to each other, that is, an expansion joint attachment/detachment device that allows the expansion joint to be attached or removed at a connection position in a piping system.

(Technical background of the invention and its problems) In a boiling water reactor, as shown in FIG. The shroud S contains a low-pressure water injection system (LP (1), which is one of the emergency core cooling systems).
) Piping W is installed by penetrating the reactor pressure vessel P. This low pressure water injection system piping W is connected to the reactor pressure vessel P.
and Schifroud S are connected by an expansion joint 1.

This expansion joint 1 has a sleeve 2 as shown in FIG.
The front and rear flanges 3゜3 are respectively fitted to the outer peripheries of the spherical seats at both ends, and the sleeve 2 is inserted so that it slides between the front and rear flanges 3 fixed between the reactor pressure vessel P and the shroud S. By inserting it, a slip joint is formed, and the relative displacement caused by the difference in thermal expansion between the reactor pressure vessel P and the shroud S in the operating state can be absorbed with a relatively short length. In order to prevent leakage from the slip joint when differential pressure occurs between the inside and outside during operation, a bellows 4 is welded between the flanges 3 so as to surround the sleeve 2, and the outer circumference of the bellows 4 is connected to a pair of front and rear joints. It is surrounded by a bellows cover 5. The expansion joint 1 has a thermal sleeve 10 welded to the nozzle of the reactor pressure vessel P.
and shroud flange 11 welded to the shroud S side.
Then, the 7 flange 3 are fitted together, and the thermal sleeve 10 and the 7 flange 3, and the shroud flange 11 and the flange 3 are connected to each other using a half-split clamp 15 to tighten the bolts and nuts 1.
7, the reactor pressure vessels P1 and shrouds S are interposed between them. At this time, the expansion joint 1 itself has seven flange 3 each with a thermal sleeve 10.
By engaging the shroud flange 11 with pins 18, the shroud flange 11 is structured so that it will not fall downward even if the clamp 15 is removed. Further, the sleeve 2 is connected to one flange 3 via a connecting pin 7, and the expansion joint 1
The structure is such that the sleeve 2 does not fall off even when the sleeve 2 is removed.

However, during operation, the bellows 4 receives a relatively large relative displacement over a short length, resulting in a high stress level, and there is usually no flow inside the expansion joint 1, resulting in a stagnation area. Due to the harsh conditions under which this equipment is used, it is considered important to periodically inspect or replace it.

However, the installation site of the expansion joint 1 itself is extremely close to the fuel, and there is a problem in terms of radiation exposure for humans to get close to it and perform attachment/detachment work. It was desired to be able to perform the attachment and detachment work by remote control.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and its purpose is to provide an expansion joint attachment/detachment device that can smoothly and reliably grip an expansion joint even underwater, and that can be remotely operated to reduce radiation exposure to workers. That's true.

[Summary of the invention]

Therefore, in the present invention, a center rod extending along the elevation direction and a guide rod extending in the left and right horizontal directions perpendicular to the center rod are provided on the base plate fixed to the operating ball that is elevated and lowered. The fixed support mechanism is connected to the cylinder rod of the opening/closing cylinder fixed to the base plate, and a link mechanism that expands and contracts in the vertical direction by being guided by the center rod as the cylinder rod moves in and out. , an opening/closing grip mechanism that opens and closes the grip that fits the bellows cover of a predetermined expansion joint, and a cylinder rod of a removable cylinder fixed to the base plate. A link mechanism that expands and contracts in the horizontal direction is connected, and a support that grips both ends of the expansion joint is opened and closed in the axial direction of the expansion joint via the link mechanism. By doing so, we succeeded in achieving the above objective.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 8.

The present invention can be roughly divided into a support mechanism 20 for suspending the entire device at a working place between the reactor pressure vessel P and the shroud S, and a support mechanism 20 for holding and suspending a predetermined expansion joint 1. It comprises an R-opening grip mechanism 30 and a telescopic attachment/detachment mechanism 50 which expands/contracts the expansion joint 1 in its axial direction to attach/detach between the reactor pressure vessel P and the shroud S.

The support mechanism 20 includes an operating ball 21 that is suspended by a crane or other device (not shown) and is lifted and lowered at the work site.
A base plate 22 having a substantially right triangular side surface is fixed to the lower end, and the base plate 22 includes a center rod 23 extending in the vertical direction, and a center rod 23 extending perpendicularly to the center rod 23 at the lower end of the center rod 23 in the left and right horizontal directions. The guide rods 25 along the guide rods are fixed to each other.

The opening/closing grip mechanism 30 also includes a cylinder rod 32 of an opening/closing cylinder 31 fixed to the upper part of the base plate 22 in the vertical direction thereof, which is fitted into the center rod 23, and is guided by the center rod 23 through the protrusion and retraction of the cylinder rod 32. A link mechanism 35 that expands and contracts in the vertical direction is connected to the tip of the cylinder rod 32, and the grip 37 to which the bellows cover 5 of the predetermined expansion joint 1 is fitted is opened and closed via the link mechanism 35. It is.

The opening/closing cylinder 31 is configured such that fluid is supplied and discharged through a hose 33 piped inside the operation ball 21.
The cylinder rod 32 is designed to move in and out along the up-and-down direction. This opening/closing grip mechanism 30 will be explained in detail according to the illustrated example. A long hole-shaped or groove-shaped elevation guide 24 is formed in the center rod 23 along the elevation direction.
The rear end of a 7-shaped link mechanism 35 consisting of a pair of links is pivotally connected to a hinge rod 34 that is movably fitted into the 1M and connected to the cylinder rod 32 of the opening/closing cylinder 31, and is opened in the bellows cover 5. The rear end of a grip 37, which is formed by swinging and intersecting a pair of hooks 38 that fit into a hanging hole 6, is pivoted to the front end of a link mechanism 35. Suspension hole 6
are the front and rear bellows covers 5 of the expansion joint 1 described above.
There are 8 hooks in total, 2 on each side, which are opened in a substantially rectangular shape, and are circular arc-shaped hooks with protrusions protruding from the inner periphery that fit into each of the hanging holes 6. 38 are crossed at a hinge 39 to form a grip 37, and the rear end of this grip 37 is pivotally connected to each link front end of the link mechanism 35 via a hinge 36. Therefore, the cylinder rod 32 in the opening/closing cylinder 31
When the hinge rod 34 is extended and protruded, the lifting guide 24
The link mechanism 35, which slides downward within the interior and is opened accordingly, separates the hooks 38 from each other, thereby releasing the grip 37.
Conversely, when the cylinder rod 32 is contracted and retracted, the grip 37 is closed and the hook 38 is fitted into the suspension hole 6, thereby suspending and supporting the expansion joint 1. .

On the other hand, the telescopic attachment/detachment mechanism 50 is attached to a cylinder rod 52 of a detachable cylinder 51 fixed to the front part of the base plate 22 in the front and back direction, and is guided by the guide rod 25 as the cylinder rod 52 comes out and goes in the front and rear horizontal direction. A link mechanism 55 that expands and contracts is connected, and a support 58 that grips both ends of the expansion joint 1 is opened and closed in the axial direction of the expansion joint 1 via this link mechanism 55. The removable cylinder 51 is configured to cause the cylinder rod 52 to protrude and retract along the front-rear direction by supplying and discharging fluid through a hose 53 piped inside the operation ball 21. This telescopic attachment/detachment mechanism 50 will be explained in detail according to the illustrated example.A central hinge 56 is slidably fitted into a long hole-shaped or groove-shaped front and rear guide 26 formed in the guide Otsudo 25 along the left and right direction. A diamond-shaped link mechanism 55 is formed, and front and rear hinges 5 at the front and rear of this link mechanism 55 are connected to each other.
7, both ends of the expansion joint 1, that is, C-shaped supports 58 along the outer peripheral surface of the flange 3 are connected, and either the front or rear of the link mechanism 55 is connected to the cylinder rod 52 of the detachable cylinder 51 via the relay rod 54. It is something. Therefore, when the cylinder rod 52 in the removable cylinder 51 is extended and protruded, the entire link mechanism 55 is extended in the front-rear direction via the relay rod 54, and at this time, the central hinges 56 approach each other within the front-rear guide 26. Therefore, the supports 58 are separated from each other, the expansion joint 1 itself is expanded, and the flange 3 end is attached to the thermal sleeve 10 on the reactor pressure vessel P side, and the shroud on the shroud S side is attached to the thermal sleeve 10 on the reactor pressure vessel P side. Conversely, when the cylinder rod 52 is contracted and retracted, the supports 58 are brought closer to each other, the entire expansion joint 1 is contracted, and separated from the thermal sleeve 10 and the shroud flange 11. shall be allowed to do so.

At this time, the detachable cylinder 51 is fixed to the front part of the base plate 22, and the cylinder rod 52 extends to the rear of the base plate 22. This is to open and separate the supports 58 from each other, and to reduce the overall length in the front-rear direction. Of course, it is possible to make them different depending on the shape, structural difference, the direction of operation of the cylinder rod 52 by supplying and discharging fluid to the removable cylinder 51, and so on.

In Figure 4. Another embodiment for ensuring the return to operation of the cylinder rod 32 in the opening/closing cylinder 31 and the cylinder rod 52 in the detachable cylinder 51 is shown. That is, the cylinder rod 32 of the opening/closing cylinder 31 in the opening/closing grip mechanism 30 is equipped with a spring 40 that elastically biases the grip 37 toward closing. 32 and a ring 41 fixed thereto, the coil is inserted in the form of a coil. By doing this, before mounting on the expansion joint 1, fluid is supplied to the opening/closing cylinder 31 to extend the cylinder rod 32 and compressing the spring 40.
When the fluid supply to the expansion joint 1 is turned off, the cylinder rod 32 is contracted by the spring 40, and the expansion joint 1 can be supported by the grip 37.

Further, the cylinder rod 52 of the attachment/detachment cylinder 51 in the telescopic attachment/detachment mechanism 50 is equipped with a spring 60 that elastically biases the expansion joint 1 toward compression in the axial direction. and a ring 61 fixed to the cylinder rod 52 in the form of a coil.

By doing this, before mounting on the expansion joint 1, the cylinder rod 52 that supplies fluid to the detachable cylinder 51 is expanded and the spring 60 is compressed. When the fluid supply is turned off, the cylinder rod 52 is contracted by the spring 60, and the expansion joint 1 can be compressed in the axial direction at the support 58.

In this way, the elastic return operation of the cylinder rods 32 and 52 is achieved by the opening/closing cylinder 31 and the detachable cylinder 5.
The system for supplying fluid to 1 can be simplified, and even if the supply source is lost, the expansion joint 1 will not be dropped midway, thereby further improving safety.

Note that the hoses 33 and 53 for supplying and discharging fluid to the opening/closing cylinder 31 and the detachable cylinder 51 are clamped as appropriate to prevent them from becoming loose and connected to the power source above via the operating ball 21. It is something that exists.

Next, the operation and use will be explained as follows.

To attach or detach the expansion joint 1, first loosen the nut 17 of the half-split clamp 15 using the long wrench 12 (see FIG. 5), and then loosen the hanging ear 16 of the clamp 15 with the hook 13. They are engaged and suspended from the thermal sleeve 10 on the reactor pressure vessel P side and from the shroud flange 11 on the shroud S side (see Fig. 6). At this time,
The expansion joint 1 is supported by the thermal sleeve 10 and the shroud flange 11 by a pin 18 provided on the flange 3 and is maintained in that state.

Therefore, the attachment/detachment device according to the present invention is suspended by the operation ball 21. At this time, by supplying fluid to the opening/closing cylinder 31 and extending the cylinder rod 32, the link [
The grip 37 is kept open via the grip 135. On the other hand, by supplying fluid to the detachable cylinder 51 and extending the cylinder rod 52, the supports 58 are kept open and separated from each other via the link mechanism 55. When the suspension is further lowered, the support 58 is fitted into the 7-lunge 3, and the grip 37 is set on the side of the bellows cover 5 at the position of the suspension hole 6. , a tapered surface 5 on the front side of each support 58.
9, this tapered surface 59 comes into sliding contact with the tapered surface of the 7 flange 3, allowing automatic positioning guidance (see FIG. 7). Next, the opening/closing cylinder 3
1 to contract the cylinder rod 32, the grip 37 closes via the link #135 and fits into the hanging hole 6. When the detachable cylinder 51 is further operated to contract the cylinder rod 52, the link The supports 58 close and approach each other via the mechanism 55, pressing both the front and rear sides of the bellows cover 5, and compressing the entire expansion joint 1 in its axial direction (see FIG. 8). By the above steps,
The expansion joint 1 can be pulled upward, and conversely, when installing the expansion joint 1, the opening/closing cylinder 31 and @removal cylinder 51 can be operated in the opposite manner.

〔Effect of the invention〕

Since the present invention is configured as described above, the expansion joint can be reliably and easily attached and detached by remote control, thereby shortening the working time and further reducing the radiation exposure of workers. This makes it possible to achieve this goal.

In particular, the grip in the opening/closing grip mechanism and the support in the telescopic attachment/detachment mechanism utilize the unique shape of the expansion joint, and since these grips and supports are opened/closed or moved in and out by the link mechanism, they are symmetrical. This provides excellent effects such as being able to reliably suspend or extend the expansion joint by replacing it with an open rll operation or an expansion/contraction operation.

[Brief explanation of the drawing]

Fig. 1 is a front view, Fig. 2 is a side view, Fig. 3 is a partially cutaway plan view, Fig. 4 is a partially cutaway front view of another embodiment, and Figs. 5 to 8 show the usage procedure. This is the fifth part of the explanation.
The figure is a side view when the clamp is removed, FIG. 6 is a side view when the clamp is moved, FIG. 7 is a side view when the TM device according to the present invention is suspended, and FIG. 8 is a side view when the clamp is moved. FIG. 9 is a sectional view of a main part of a boiling water reactor equipped with an expansion joint, and FIG. 10 is a cross-sectional perspective view of the expansion joint. P...Reactor pressure vessel, S...Shroud, F...
・Fuel assembly, W...low thickness water injection system, 1...expansion joint 2.2...sleeve, 3...flange, 4...bellow, 5...bellow cover, 6...・Suspension hole, 7...
・Connection bottle, 10... Thermal sleeve, 11...
Shroud flange, 12... Wrench, 13... Hook, 15... Clamp, 16... Hanging ear, 17...
...Nut, 18...Bin, 20...Support mechanism, 2
1... Operation ball, 22... Base plate, 23
... Center rod, 24 ... Lifting guide, 25.
...Guide rod, 26...Front and rear guide, 30...
Opening/closing grip mechanism, 31... Opening/closing cylinder, 32...
- Cylinder rod, 33... Bose, 34... Hinge rod, 35... Link mechanism, 36... Hinge, 37
...Grip, 38...Hook, 39...Hinge, 40...Spring, 41...Ring, 50...
- Telescopic attachment/detachment mechanism, 51... Attachment/detachment cylinder, 52...
Cylinder rod, 53... Hose, 54... Relay rod, 55... Link mechanism, 56... Central hinge,
57... Front and rear hinges, 58... Support, 59...
・Tapered surface, 60...spring, 61...ring. Applicant's agent Hisashi Hatano Figure 1 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A center rod extending in the elevation direction and a guide rod extending in the left and right horizontal directions perpendicular to the center rod are fixed to a base plate fixed to an operating ball that is elevated and lowered. A link mechanism is connected to the cylinder rod of the opening/closing cylinder fixed to the base plate, and the link mechanism expands and contracts in the vertical direction as the cylinder rod moves in and out while being guided by the center rod. The opening/closing grip mechanism opens and closes the grip that fits the bellows cover of a given expansion joint, and the cylinder rod of the removable cylinder fixed to the base plate is guided by a guide rod as the cylinder rod comes out and goes back and forth. A telescopic attachment/detachment mechanism is provided in which a link mechanism that expands and contracts in the horizontal direction is connected, and a support that grips both ends of the expansion joint is opened and closed in the axial direction of the expansion joint via the link mechanism. A device for attaching and detaching expansion joints. 2. The opening/closing grip mechanism has a rear end of a link mechanism consisting of a pair of links, which is slidably fitted into a lifting guide formed on the center rod along the lifting direction, and connected to a hinge rod connected to the cylinder rod of the opening/closing cylinder. At the same time as pivoting the
The attachment/detachment device for an expansion joint according to claim 1, wherein the rear end of the grip, which is formed by swinging and intersecting a pair of hooks that fit into a hanging hole opened in the bellows cover, is pivotally attached to the front end of a link mechanism. 3. The telescopic attachment/detachment mechanism forms a diamond-shaped link mechanism in which a central hinge is slidably fitted to front and rear guides formed at both ends of the guide rod along the left-right direction, and the front and rear hinges of this link mechanism The expansion joint according to claim 1 or 2, in which C-shaped supports along both ends of the expansion joint are connected, and either the front or rear of the link mechanism is connected to the cylinder rod of the detachable cylinder via a relay rod. attachment/detachment device. 4. The cylinder rod of the opening/closing cylinder in the opening/closing grip mechanism is equipped with a spring that elastically biases the grip toward closing.
The attachment/detachment device for an expansion joint according to any one of paragraphs. 5. The telescopic device according to any one of claims 1 to 4, wherein the cylinder rod of the removable cylinder in the telescopic removable mechanism is equipped with a spring that elastically biases the expansion joint toward compression in the axial direction. Attachment and detachment device for fittings.