JPS58178290A - Reactor container structure - 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 The present invention relates to an improvement of nine nuclear reactor vessel structures equipped with a photographing mechanism, and particularly to a nuclear reactor vessel structure that improves the safety of a suspended type reactor main vessel against severe earthquake forces.

A suspended nuclear reactor vessel generally consists of a tank-type main vessel that houses the reactor core and core structures and forms a coolant boundary around them, and a safety vessel that extends around the outside of this main vessel. These contents S are suspended from a roof slab serving as a common lid. The tank-type main vessel has a large-diameter, thin-walled structure for the purpose of alleviating thermal stress and reducing manufacturing costs, so it is necessary to take into account possible vibrations between the built-in fluid and the main vessel wall, such as sloshing and bulging during earthquakes. Yes, q
In the case of the llK suspension structure, a support structure for the outer wall of the main container was required as a countermeasure against the seismic behavior of each container.

However, conventional support structures have various problems. For example, in a method where the main container is supported by a safety container using an elastic spring or oil-based dashpot, the damper becomes directional and has no supporting force against seismic waves that cannot be predicted from which direction. It won't be uniform.

In order to install the damper, the damper sequential sealing part and their reinforcement S are required on both the main container and the safety container.
If these sealing parts and reinforcement parts are formed, the main container will have a non-uniform plate thickness structure, which will easily cause thermal stress problems, and will also lead to failures such as in-service inspections (I8I). Increasing the overall thickness of the main container in order to achieve a uniform plate thickness not only significantly increases the cost of counterfeiting, but also causes thermal stress problems.

Furthermore, if the main container and the safety container are filled with fluid or the like, there is a problem that the main container welding part I8I cannot be formed.

Main issue 11! This was made to eliminate the above-mentioned drawbacks of the conventional device, and it is possible to weld the main container part III.
The present invention aims to provide a nuclear reactor vessel structure 'f that is easy to construct and is equipped with a vibration isolation mechanism that has excellent anti-seismic properties.

The present invention will be described in detail below with reference to the illustrated embodiments.

In FIG. 1, a reactor vessel 1ii1ic has a watertight safety vessel 4 whose upper end is fixed to a roof slab 2. The internal pressure of this safety container is strangely that a main container 5 with a medium to small diameter and length is arranged, and is fixed to a 4Fi roof frame 2 to form a hanging structure. The roof slag 2 is installed on the roof surface with its peripheral portion directly supported on the support part 6. The iC inside the main vessel 5 is the reactor core 7 and the reactor internal structure! It! 118 is housed, and the surrounding area VCf is filled with liquid sodium, M9, which is a coolant. Lord 1! A cover 3 covering the welded part is attached to the main container 5 to maintain an airtight structure.
Nito 9 is attached b.

Further, liquid sodium 10 is filled between the main container 45 and the safety container 4 as a fluid damper medium.

In the defense 4M4w of the present invention configured as described above,
When the main passenger unit 5 is heated up at the start of operation, it thermally expands in the axial direction, but since its outer periphery is filled with liquid sodium 10, the thermal expansion of the main passenger unit 5 is absorbed by the movement of this liquid sodium. and therefore safe @′
There is no natural restraining force between it and a4.

However, when an earthquake occurs and the seismic waves propagate from the 4+1 roof through the reactor vessel m1ll and the roof slab 2 and act on the main passenger unit 5, the main passenger i5 receives the acceleration and tries to take a picture. At this time, the IJum 10 exerts a force in the direction of suppressing the acceleration of the main passenger 45 (liquid filled between it and the safety container 4), so the force received by the main container 5 is alleviated, and therefore the large seismic force is Even if it acts, it will not be damaged.

9. Fill 10 tons of liquid sodium between the main passenger unit 5 and the safety vessel 4 to not only function as a damper medium as described above, but also to be used in case an accident such as melting of the reactor core occurs. Since it is used as a coolant, the safety container functions as a 4-piece core catcher.

Furthermore, since the cover 3 is installed in the main container 5 [1 part and sealed with a damper medium, by sampling gas from this part and guiding it to the aerosol sampling mNa leak detector, it becomes possible to perform the molten P4 part I8I. In the above explanation, an example was described in which IJum 10 was filled between the main container 5 and the safety container A4, but the present invention is not limited to this, and for example, as shown in Figure 2, Damper media 11 such as ticks, sand, balls, etc. can also be used. Additionally, as shown in the figure, if 12t of braking fins are protruded from the outer surface of the main f1.55, the braking force will increase when the main passenger unit 5 receives acceleration force, thereby further improving earthquake resistance. .

Furthermore, in the method of Wang Yongjin 5 welding part I81, as long as the cover 3 is provided, a contact type Na leak detector may be installed;
This can also be done by installing a rail inside the cover and driving the inspection side 6 using a UT or the like.

As described above, according to the present invention, it is possible to avoid the local reaction force that occurs due to the attachment of a damper such as a conventional elastic spring Yadashbonoto, and there is no need to reinforce the main container to provide support. A main vessel without thermal problems can be used. Further, since the damper according to the present invention has no directionality, it can sufficiently deal with the ground 1 from any direction.

Furthermore, even when a tie is made between the main container and the safety container, ISI of the welded portion of the main container can be performed.

[Brief explanation of the drawing]

1 and 2 are longitudinal sectional views of the reactor vessel structure in one embodiment of the present invention, respectively. 2 Roof slab 3 Cover 4 Safety container 5 Main container 10 Liquid sodium 11 Damper medium 12
Fin (7317) Agent Patent Attorney Noriyuki Chika (
1 other person) Figure 1

Claims (1)

[Claims] 1. Suspend the reactor main vessel and the safety vessel that covers it from the same roof slab, fill the gap between the main vessel and the safety vessel with a fluid damper medium, and Outside welding area m
Nuclear reactor structure 02, characterized in that the main vessel has a braking fin on its outer wall. 3. The reactor vessel structure according to claim 1, characterized in that the fluid damper medium is made of a liquid such as +1 um. reactor vessel structure.