JPS6280587A - Pressure vessel device for nuclear reactor and assembling method thereof - 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 a nuclear reactor pressure vessel device that has an improved combination configuration of a reactor pressure vessel installed in a nuclear power plant and a steel formwork that shields the surrounding area. and its assembly method.

[Technical background of the invention and its problems]

A nuclear reactor pressure vessel is a container that houses the heart of a nuclear reactor, such as fuel, control rods, and a steam/water separator. This reactor pressure vessel is located inside the reactor containment vessel and is fixed to the head of the pedestal by a cylindrical skirt provided on the lower head plate of the reactor pressure vessel. It is shielded by a steel formwork surrounding it.

In addition, a large number of 5 main steam pipe nozzles, water supply pipe nozzles, spray pipe nozzles, and recirculation wood pipe nozzles protrude around the reactor pressure vessel, and each pipe from these various nozzles penetrates the steel formwork. It is installed to connect to each compatible device.

Therefore, in the assembly equipment for the reactor pressure vessel, pedestal, and steel formwork, the conventional assembly sequence is to fix the reactor pressure vessel and the steel formwork separately to the top of the pedestal, and then fix the above-mentioned various piping. Pass it inside the steel formwork through the opening,
The conventional method was to connect it to the nozzle end protruding around the reactor pressure vessel and then fix it by welding.

However, the connection work between the nozzle end of the reactor pressure vessel and the piping is approximately 1m between the 1M slave reactor pressure vessel and the steel formwork.
The workers had no choice but to perform welding and other tasks in an awkward position, leaning into the reactor pressure vessel through the opening of the steel formwork. Also, when a nuclear power plant starts operating and periodically inspects the connection between the nozzle end and piping, inspectors insert their bodies through the opening of the steel formwork and inspect while clinging to the opening. We are verifying the soundness of the system.

[Purpose of the invention]

It is an object of the present invention to provide a nuclear reactor pressure vessel, a pedestal, and a steel formwork that can be easily assembled and configured, and that can also easily connect nozzles and piping protruding around the reactor pressure vessel. The present invention provides a furnace pressure vessel device and a method for assembling the same.

[Summary of the invention]

The reactor pressure vessel device according to the present invention has a combination configuration of a reactor pressure vessel fixed to the top of a pedestal in a 1M sub-reactor containment vessel and a m-shaped formwork concentrically surrounding the outside of the reactor pressure vessel,
The dimension of the nozzle protruding into the reactor pressure vessel is such that it protrudes to the outside of the steel formwork, and the ll formwork is divided into a plurality of sections along its circumferential direction, and the nozzle is cut and divided in the longitudinal direction. It is characterized by being composed of a combination of a plurality of steel formwork blocks each having an opening through which a nozzle protruding from the furnace pressure vessel passes.

Further, the method for assembling a nuclear reactor pressure vessel device according to the present invention includes:
In a combined configuration of a reactor pressure vessel fixed to the top of a pedestal in the reactor containment vessel and a steel formwork concentrically surrounding the outside of the reactor pressure vessel, the dimensions of the nozzle protruding into the reactor pressure vessel are as follows. m'I5 The length should protrude outside the formwork,
The fI formwork is divided into a plurality of sections along its circumferential direction, and a plurality of pieces of steel are cut and divided in the longitudinal direction and each has an opening through which a nozzle protruding from the reactor pressure vessel passes. A formwork block is provided, and before fixing the reactor pressure vessel and the steel formwork to the pedestal, each steel formwork block is inserted into the outer peripheral side of the reactor pressure vessel while passing a nozzle through its opening. After temporarily attaching the steel formwork blocks concentrically at intervals, the joints of each steel formwork block are made into an integral structure by welding, and then the integrated reactor pressure vessel and steel 1-tatami formwork are attached to the pedestal. It is characterized by fixing the nozzle, connecting piping to the end of the nozzle, and then filling the steel formwork with concrete to configure the entire steel formwork as a radiation shield.

[Embodiments of the invention]

Embodiments of the present invention shown in the drawings will be described below. In FIG. 1, a reactor pressure vessel 1 constituting a reactor pressure vessel apparatus according to the present invention has a cylindrical skirt 2 provided on its lower end plate, which allows the top of a pedestal 3 to protrude from the bottom of a reactor containment vessel 30 to Fixed. Inside the reactor containment vessel 30, a dry well 5 is formed by a diaphragm floor 4.
and a suppression chamber 6, and the dry well 5 and the suppression chamber 6 are communicated with each other through a plurality of vent pipes 7. Further, the steel formwork frame constituting the reactor pressure vessel apparatus of the present invention is fixed to the top of the pedestal 3 and concentrically surrounds the outside of the reactor pressure vessel 1 at predetermined intervals.

Therefore, in the present invention, the length of the nozzles 90, such as the main steam pipe nozzle, spray pipe nozzle, and recirculation wood pipe nozzle, provided around the reactor pressure vessel 1 is adjusted slightly to the outside of the steel formwork. It is selected as follows. Further, the steel formwork stands are made of steel formwork blocks 8a, 8b, and 8c that are divided into multiple sections in the circumferential direction and cut in the longitudinal direction, as shown in FIGS. 2 and 3.

It is composed of a collection of 8d.

Each of the blocks 88 to 8d constituting the steel formwork -β- has an outer plate 9 of the same curvature, as shown in detail in FIG.
8 to 9d and inner plates 10a to 10d, both plates 9
A to 9d and 10a to 10d are maintained at intervals by supports 11, and a temporary support 12 is provided between the inner plate 10 and the reactor pressure vessel 1 to maintain the interval. Further, the bottom of the space formed by the outer plates 98 to 9d and the inner plates 10a to 10d of each of the blocks 88 to 8d is closed by the bottom plates 13a to 13d.

Furthermore, in the present invention, the various nozzles 90 of the reactor pressure vessel 1 protrude through the ll-made formwork -β-, and the blocks 8a and 8 through which the nozzles 90 penetrate
Openings 14a and 14b are provided at opposite locations of b, and the nozzle 90 is passed through the openings 14a and 14b. In the openings 14a, 14b, the space between the outer plates 9a, 9b and the inner plates 10a, lob is closed by a prismatic partition plate 15.

Next, a procedure for assembling the nuclear reactor pressure vessel device according to the present invention will be explained. Outside the reactor containment vessel 30,
First, the steel formwork blocks 8a and 8b through which the nozzle 90 of the reactor pressure vessel 1 passes are opened at their openings 14a and 14b.
The temporary support 12 is moved close to the outside of the reactor pressure vessel 1 so that the nozzle 90 comes out from the reactor pressure vessel 1 and the inner plate 1.
Install between 0a and 10b.

After this, the steel formwork block 8c that the nozzle 90 does not penetrate
, 8d are inserted between the blocks 8a and 8b and brought close to the reactor pressure vessel 1. When the reactor pressure vessel 1 is brought close to the predetermined position, a temporary support 12 is attached and fixed between the reactor pressure vessel 1 and the inner plates 10c and 10d.

In this way, the outer plates 98 to 9 of each steel formwork 88 to 8d
d and the inner plates 10a to 10d have a structure that surrounds the reactor pressure vessel 1 in a concentric relationship. Then, make sure that the top and bottom surfaces of each block 88 to 8d are on the same plane↓
After this correction, the outer plates 9a~ of each block 88~8d
9d, inner plates 10a to lOd and bottom plate 13a"13d
A cylindrical steel formwork l is constructed by fixing the joints by welding.

In this way, the reactor pressure vessel 1 and the steel formwork l are lifted up by the lifting machine 16 and gently lowered to the top of the pedestal 3, as shown in FIG. In addition, the lower part of the steel formwork stand is directly fixed to the pedestal 3. After the reactor pressure vessel 1 and the steel form stand are fixed to the top of the pedestal 3, the piping 17 is connected and fixed to the tip of the nozzle 90 protruding to the outside of the steel form stand.

The connection work between the nozzle 90 and the piping 17 can be performed in a place where there is a relatively large space outside the steel formwork stand, so it can be performed efficiently and easily. Also m
Outside plates 98 to 9 of each block 88 to 8d of m formwork once -
The space between d and the inner plate 10a=10d is poured and filled with concrete, and the entire steel form stand is configured as a radiation shield.

Note that the number of divisions of the steel formwork -β- does not necessarily have to be equal, and can be any number and unequal, taking into account the protruding location of the nozzle 90, etc.

〔Effect of the invention〕

As described above, in the present invention, the steel formwork that surrounds the outside of the reactor pressure vessel is divided into multiple sections along the circumferential direction, cut vertically, and divided, and the nozzle protruding from the reactor pressure vessel penetrates the steel formwork. The reactor pressure vessel and steel formwork can be temporarily assembled together and then fixed to the top of the pedestal inside the reactor containment vessel. Therefore, the assembly work period can be shortened, and in particular, the work of connecting nozzles and piping can be done in a large work area outside the steel formwork, which improves the safety of work such as connection and welding. In addition, inspection of the welded part between the nozzle and piping during assembly and operation can be done outside the m-made formwork, improving inspection work efficiency and reducing radiation exposure for inspectors. be able to.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view showing one embodiment of the reactor pressure vessel device according to the present invention, FIG. 2 is a front view showing the combination structure of the reactor pressure vessel and the steel formwork, and FIG. FIG. 1... Reactor pressure vessel 3... Pedestalt... Steel formwork 88-8d... Steel formwork blocks 98-9
d...Outer plate 10a-10d...Inner plate 14
... Opening 17 ... Piping 30 ... Reactor containment vessel 90 ... Nozzle agent Patent attorney Yoshiaki Inomata (and one other person) Figure 1

Claims (3)

[Claims] (1) In a combination configuration of a reactor pressure vessel fixed to the top of a pedestal in the reactor containment vessel and a steel formwork concentrically surrounding the outside of the reactor pressure vessel, a nozzle protruding into the reactor pressure vessel The steel formwork is divided into a plurality of sections along its circumferential direction, and the nozzle protruding from the reactor pressure vessel penetrates the steel formwork. 1. A nuclear reactor pressure vessel device comprising a combination of a plurality of steel formwork blocks each having an opening. (2) The reactor pressure vessel apparatus according to claim 1, wherein the plurality of blocks of the steel formwork are divided into blocks through which the nozzle penetrates and blocks through which the nozzle does not penetrate. (3) In a combined configuration of a reactor pressure vessel fixed to the top of a pedestal in the reactor containment vessel and a steel formwork concentrically surrounding the outside of the reactor pressure vessel, a nozzle protruding into the reactor pressure vessel an opening having a length protruding from the outside of the steel formwork, the steel formwork being divided into a plurality of sections along its circumferential direction, cut and divided vertically, and through which a nozzle protruding from the reactor pressure vessel penetrates; A nozzle is passed through each steel formwork block through its opening before fixing the reactor pressure vessel and the steel formwork to the pedestal. After temporary installation concentrically at intervals on the outer circumference of the reactor pressure vessel, the respective joints of each steel formwork block are welded into an integral structure, and then the integrated reactor pressure vessel and The steel formwork is fixed to the pedestal, piping is connected to the end of the nozzle, and the steel formwork is then filled with concrete, making the entire steel formwork a radiation shield. A method of assembling a nuclear reactor pressure vessel device.