JPS5975188A - Reactor pressure vessel supporting device - 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 provides seismic support for a reactor pressure vessel of a nuclear power plant in the horizontal direction, and prevents displacement in the vertical direction due to thermal expansion of the vertically elongated reactor pressure vessel. The present invention relates to a support device for a nuclear reactor pressure vessel.

The reactor pressure vessel is a vessel that houses the reactor core containing nuclear fuel inside, and as shown by reference numeral 1 in Figure 1, it has the shape of a vertical cylinder placed on a pedestal 3 inside the reactor containment vessel 2. will be installed. The reactor containment vessel 2 is covered with a biological shielding wall 4 made of a concrete wall and is installed on the foundation floor 5 of one reactor building. Further, a reactor shielding wall 6 is placed around the reactor pressure vessel up to the top, and a top plate 7 at the upper end thereof is connected to the inner surface of the reactor containment vessel 2 to maintain rigidity.

Conventionally, a reactor pressure vessel stabilizer 8 as shown in FIGS. 2 and 3 has been used as an earthquake-resistant support device for the reactor pressure vessel 1 having such a configuration. That is,
The reactor pressure vessel stabilizer 8 includes a stabilizer sole plate 9 on the top plate 7 of the reactor shielding wall 6.
A stabilizer bracket (11) to which a gusset 10 is welded, and this gusset 10 protrudes from the outer surface of the reactor pressure vessel 1
is clamped and tightened by a disc spring 12 to suppress horizontal vibration of the reactor pressure vessel 1 during an earthquake. The reactor pressure vessel stabilizer 8 is provided with a plurality of stabilizers distributed at equal intervals around the reactor pressure vessel 1, and is resistant to earthquakes in all directions.

[Problems with background technology]

Because the reactor pressure vessel 1 is functionally heated to a high temperature, thermal expansion occurs, and the amount of displacement in the vertical direction is particularly large due to its elongated cylindrical shape. The reactor pressure vessel stabilizer 8 is provided with a gusset 1 in advance so as not to restrict displacement in the vertical direction.
0, a vertical space corresponding to the amount of displacement is provided. However, since the stabilizer bracket 11 of the reactor pressure vessel stabilizer 8 is strongly tightened in the horizontal direction, thermal expansion in the vertical direction is constrained by this tightening surface, resulting in the generation of unnecessary stress somewhere. ing. If this acts as locally concentrated stress or repeated stress, it may lead to deterioration or damage to the member.

[Purpose of the invention]

The present invention takes the above-mentioned points into consideration, and makes it possible to suppress horizontal vibrations caused by earthquakes and prevent the generation of unnecessary stress without restricting the vertical thermal expansion of the reactor pressure vessel. The purpose is to provide a support device for a nuclear reactor pressure vessel.

[Summary of the invention]

In order to achieve the above object, the present invention provides a laminar bearing in which metal plates and hard rubber are alternately laminated. Focusing on the fact that the reactor pressure vessel has an extremely low characteristic, multiple lance bearings are installed between the outer surface of the reactor pressure vessel and the reactor shielding wall surrounding it, with the direction of stacking parallel to the diameter of the pressure vessel. The present invention provides a reactor pressure vessel support device that is arranged and interposed in accordance with the direction.

[Embodiments of the invention]

Embodiments of the present invention will be described with reference to FIG. 4 and subsequent figures.

Since the structure of the reactor pressure vessel and its surroundings is the same as in FIG. 1, each part is given the same reference numeral and a description thereof will be omitted.

The latitude bearing 13 used in the present invention is constructed by alternately laminating metal plates 14 and hard rubber 15, and welding the negative side onto the latitude bearing sole plate 16. There is a gap 17 between the outer surface of the reactor pressure vessel 1 and the reactor shielding wall 6, and within the gap 17, a pedestal 18 is provided protruding from the inner surface of the reactor shielding wall 6, and a pedestal 18 is mounted on the pedestal 18. - Tighten the bearing sole plate 16. U-U-
The direction of the laminated structure of the bearing 13 faces outward in the diametrical direction of the reactor pressure vessel 1, and the tip surface 1.3a faces the outer surface of the reactor pressure vessel 1 with a slight gap therebetween. Since the reactor pressure vessel 1 is cylindrical, the tip surface 13a is
As shown in FIG. 6, it is curved in the circumferential direction so that slight gaps are distributed over the entire surface. This gap is the reactor pressure vessel 1
filled by thermal expansion. A plurality of such lance bearings 13 are arranged at equal intervals in the circumferential direction of the reactor pressure vessel 1, and are configured as an earthquake-resistant support device for the reactor pressure vessel 1.

Next, we will discuss the effect.

The Lano Bearing 13 has the characteristic that it can bear a large compressive load in the stacking direction, but has extremely low shear patency in the normal direction, and depending on the design, the spring constant in the compression direction is 1000 times the spring constant in the shear direction. It can be set to a certain degree. Horizontal vibrations of the reactor pressure vessel 1 due to an earthquake are suppressed by the large compression spring constant of the latitude bearing 13, thereby fully demonstrating its performance as an earthquake-resistant support.

On the other hand, the longitudinal elongation due to thermal expansion of the reactor pressure vessel 1 acts on the laminar bearing 13 as a considerable amount of displacement accumulated at the upper end, but as described above, the laminar pair 13 acts in the shear direction. Since its spring constant is extremely low, it easily follows its displacement and does not constrain the longitudinal thermal expansion of the reactor pressure vessel.

FIG. 7 shows another embodiment of the invention. A slide frame that is rigid in the circumferential direction and has a friction damper function is combined on both sides of the rough bearing 13. The slide frame is fitted into a base frame 21 fixed to the reactor shielding wall 6 so as to be able to slide up and down.
It is pressed inward by the spring 22 to press the front friction plate against the reactor pressure vessel 1.

With the above-described structure, the latitude bearing 3 suppresses the vibration of the reactor pressure vessel 1 in the compression direction during an earthquake by its high compression spring constant. The spring 22 of the slide r-frame condyle also assists in part. Torsional vibration of the reactor pressure vessel 1 or compressive load vibration deviated from the front as shown in FIG. 8 functions to suppress it. For longitudinal displacement due to thermal expansion of the reactor pressure vessel 1,
U-N - Bearing 13 and slide frame B should not be restrained.

〔Effect of the invention〕

As explained above, in the reactor pressure vessel support device according to the present invention, a lance bearing having high rigidity in the compression direction and low rigidity in the shear direction is installed between the reactor pressure vessel and the reactor shielding wall. By interposing the reactor pressure vessel and making use of its characteristics, it is possible to suppress the horizontal vibration of the reactor pressure vessel and provide seismic support, while allowing almost free displacement in the vertical direction without restricting thermal expansion. Therefore, unnecessary stress due to thermal expansion is not generated, and the safety of the reactor pressure vessel and its surrounding members is increased. In addition, since the laminar bearing itself is used, the device can be simplified and costs can be reduced, which has the effect of improving both the function as an earthquake-resistant support and the economic efficiency.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view schematically showing the main parts of a nuclear power plant, Fig. 2 is a plan view showing a conventional reactor pressure vessel support device, Fig. 3 is a side view of the same, and Fig. 4 is a nuclear reactor according to the present invention. A cross-sectional view of the main parts of a nuclear power plant equipped with a pressure vessel support device, Figure 5 is
FIG. 6 is an enlarged cross-sectional view of part A in the figure, FIG. 6 is an enlarged cross-sectional plan view taken along the arrow B-B in FIG. FIG. 8 is an explanatory diagram illustrating the operation. ■...Reactor pressure vessel, 2...Reactor containment vessel, 6
...Reactor shielding wall, 13...Rano-bearing,
14...Metal plate, 15...Hard rubber, 17...Gap, Red...Slide frame, n...Friction plate. Applicant's agent Hideo Hatano 2 Figure 3 Figure 4 Figure 4 /7 Figure 6

Claims (1)

[Claims] 1. Between the outer surface of the reactor pressure vessel and the inner surface of the reactor shielding wall surrounding it, a plurality of lano-4 rings are arranged at appropriate intervals in the circumferential direction. A support device for a nuclear reactor pressure vessel, characterized in that it is interposed. 2. The Lanosse bearing is constructed by alternately laminating metal plates and hard rubber, and is interposed with the lamination direction aligned with the diameter direction of the reactor pressure vessel. Furnace pressure vessel support device.