JPS6296894A - Horizontal supporter for boiling water type reactor pressurevessel - Google Patents

Abstract

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

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a horizontal support device for a boiling water reactor pressure vessel.

(Technical background of the invention and its problems) Reactor pressure vessel (hereinafter abbreviated as RPV) of a boiling water reactor
As shown in FIG. 6, the RPV pedestal 3 is installed in the reactor containment vessel 2 (hereinafter abbreviated as PCV), and an RPV stabilizer 5 is installed between the RPV 1 and the reactor heat shielding wall 4. A PC is installed between the reactor heat shield wall 4 and the PCV 2.
A truss 6 is provided, and the structure is such that the RPV stabilizer 5 and the PC truss 6 suppress horizontal displacement of the RPV 1 during an earthquake and transmit seismic force to the reactor building 7.

However, in the above structure, RPVI and reactor heat shield l! ! Since there is an RPV stabilizer 5 between 4 and 4, the RPV
When inspecting the weld between I and the main steam pipe 8, the RPV stabilizer 5 became an interference, and there was a problem in that the I5I (in-service inspection) could not be carried out as expected.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to develop a boiling water reactor pressure vessel that can suppress the horizontal displacement of RPV during an earthquake without hindering the implementation of ISI. The object of the present invention is to provide a horizontal support device.

[Summary of the invention]

The horizontal support device for a boiling water reactor pressure vessel according to the present invention installs a bracket on the top of the reactor heat shielding wall or the top slab of the reactor containment vessel to horizontally hold the main steam piping, This system is characterized by suppressing horizontal displacement of the reactor pressure vessel.

[Embodiments of the invention]

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

FIG. 1 is a longitudinal cross-sectional view of a nuclear reactor building showing one embodiment of the present invention, and FIG. 2 is a view taken along the line ■--■ in FIG. 1. In Figure 1, 101 is RPV and 102 is concrete PCV.
Then, RPVlol connects P via RPV skirt 101a.
It is installed on an RPV pedestal 103 erected inside the CV 102. Further, 104 is a reactor heat shielding wall surrounding the outer periphery of the RPVlol, and a bracket 109 is installed on the top of this heat shielding wall 104 as shown in FIG. This bracket 109 is provided with the main steam pipe 108 in between, and has a structure that does not restrict the main steam pipe 108 in the axial direction and the vertical direction. Supports 110 support the bracket 109 on both sides to prevent it from falling sideways.
is supported by In addition, 102a in the figure is PCV102
This is the top slab.

In this way, the main steam pipe 1 is installed at the top of the reactor heat shield wall 104.
By installing the bracket 109 that horizontally holds the RPVlol, the horizontal displacement of the RPVlol during an earthquake can be suppressed by the bracket 109 alone.
There is no need to provide an RPV stabilizer between Vlol and the reactor heat shield wall 104. Therefore, since it is possible to remove the RPV stabilizer, which was an interference in the past, the RP
Inspection of the weld between Vlol and the main steam pipe 108, etc. can be easily carried out.

Note that the present invention is not limited to the above embodiments,
For example, as shown in FIG.
It may be attached to the top slab 102a of 02. Also,
If the seismic force is not directly transmitted to the bracket 109 due to the design of the main steam pipe 108, etc., the fourth
As shown in the figure, a dashbot 111 may be interposed between the bracket 109 and the main steam pipe 108. Roughly speaking, there is no problem when the installation angle θ of the main steam pipe 108 with respect to RPVlol is 90° as shown in Fig. 5(a), but if θ is 90° as shown in Fig. 5(b), is RP
A plurality of dummy supports 112 may be attached to the outer periphery of Vlol, and these dummy supports 112 may be held between brackets 109.

(Effects of the Invention) As described above, according to the present invention, by installing brackets that horizontally sandwich the main steam piping on the top of the reactor heat shield wall or the PC top slab, the horizontal direction of the RPV during an earthquake can be improved. RPV because displacement can be suppressed only with the bracket
It is possible to easily inspect the outer circumferential welded part and shorten the ISI implementation period.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of a reactor building showing one embodiment of the present invention, FIG. 2 is a view taken along the ■-■ arrow in FIG. 1, and FIGS. 3 and 4 are other embodiments of the present invention. Front view of the bracket showing the fifth
The figure shows that the installation angle of the main steam piping with respect to the RPV is θ (900
FIG. 6 is a longitudinal sectional view of a reactor building showing a conventional example. 101...RPV (reactor pressure vessel), 102...
PCV (reactor containment vessel), 103...RPV pedestal, 104...reactor heat shield wall, 108...main steam piping, 109...bracket. Applicant's representative Patent attorney Takehiko Suzue Figure 2 Figure 3 Figure 5 Figure 6

Claims (1)

[Claims] In a boiling water reactor pressure vessel installed on a reactor pressure vessel pedestal installed upright in a reactor containment vessel and surrounded by a reactor heat shield wall, the top of the reactor heat shield wall or the reactor A boiling water reactor pressure vessel characterized in that a bracket is installed on the top slab of the containment vessel to horizontally sandwich the main steam piping, and this bracket suppresses horizontal displacement of the reactor pressure vessel during an earthquake. Support device.