JPS593293A - Fast breeder container - 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 to which the invention pertains] This invention aims to increase the allocation effect of the upper core mechanism and the core within the reactor vessel when horizontal vibration occurs in the fast breeder reactor vessel due to an earthquake. The present invention relates to a fast breeder reactor vessel characterized by:

[Prior art and its problems]

Figure 1 schematically shows the reactor structure of a conventional tank-type fast breeder reactor, in which a main vessel 2 filled with liquid sodium is housed in a concrete structure 3 and suspended from a roof slab 4. . In addition to the core 5, the main vessel 2 has a structure in which a circulation pump 7 and a heat exchanger 6 are suspended from the roof slab 4. Further, a core upper mechanism 8 is installed inside the suspension shell 9 that suspends the core, and performs operations such as driving control rods.

In this way, the tank-type fast breeder reactor has the circulation pump 7 and the heat exchanger 6 built into the main vessel 2;
And the roof slab 4 becomes very large.

By the way, if a large seismic force is applied to the main vessel and the roof slab, horizontal vibrations will occur in the core and core upper mechanism suspended by the roof slab inside the main vessel.

As described above, when the vibrations of the core and upper core mechanism become large, the lateral seismic load becomes excessive, and it becomes a problem whether the core integrity can be maintained.

[Purpose of the invention]

The purpose of this invention is to increase the allocation effect of the reactor core and upper core mechanism when horizontal vibrations occur due to an earthquake, thereby reducing the seismic response in the horizontal direction and increasing the safety of the nuclear reactor.

[Summary of the invention]

Multiple rows of plate-shaped vanes, which serve as vibration damping members, are installed on the outer periphery of the lower core of the upper core mechanism in the fast breeder reactor vessel and the hanging shell that suspends the core. When the reactor core and upper core mechanism vibrate due to an earthquake, the plurality of vanes receive fluid resistance equal to their horizontal cross-sectional area, which can act as a resistance force against the vibrations.

In this way, the fluid resistance acting on the vanes increases the vibration damping effect of the core and upper core mechanism.

〔Effect of the invention〕

Horizontal fluid resistance is increased and horizontal vibrations are controlled by providing multiple rows of vanes, which are vibration damping members, on the upper core mechanism inside the fast breeder reactor vessel and on the outer periphery of the lower part of the hanging shell that suspends the reactor core. It can increase the vibration effect and improve the safety of the nuclear reactor.

[Embodiment of the Invention] An embodiment of the invention will be described with reference to FIGS. 2 and 3. Note that the same parts as in FIG. 1 are given the same reference numerals and their explanation will be omitted.

A plurality of rows of plate-shaped vanes 11, which are vibration damping members, are attached to the lower outer circumference of the suspension shell 9 that suspends the core upper mechanism 8 and the reactor core 5 in the fast breeder reactor vessel.

When the core 5 and the upper core mechanism 8 vibrate due to an earthquake, the vibration damping effect of the core 5 and the upper core mechanism can be increased by suppressing the horizontal vibration by the fluid resistance acting on the plurality of vanes 11. I can do it.

[Brief explanation of drawings]

FIG. 1 is a sectional view schematically showing a conventional tank-type fast breeder reactor vessel, FIG. 2 is a plan view showing an embodiment of a vibration damping member according to the present invention, and FIG. 3 is a tank-type fast breeder reactor vessel according to the present invention. FIG. 1 is a schematic cross-sectional view of one embodiment of a breeder reactor vessel. 1...Safety container 7...Circulation pump 2...
Main vessel 8... Core upper mechanism 3... Concrete structure 9... Lifting shell 4... Roof slab 7" 10... Conical? Bow) 5.
... Furnace core 11 ... Plate-shaped vane plate 6 ...
Heat exchanger

Claims (1)

[Claims] A fast breeder reactor reactor vessel characterized in that a plurality of rows of vanes serving as vibration damping members are provided on the outer periphery of the lower part of a suspension shell that suspends a reactor core upper mechanism and a reactor core within the fast breeder reactor reactor vessel.