JPH0513225B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a construction method for a nuclear reactor in a nuclear power plant, and particularly to improvements in a reactor building and lifting equipment.

[Technical background of the invention and its problems]

Conventionally, in a reactor building that houses a nuclear reactor in a nuclear power plant, extremely large structures such as a reactor containment vessel and a pressure vessel are transported and installed using a large tower crane or the like at the same time as the reactor building is constructed. Large equipment such as reactor internal structures that cannot be brought in after the reactor building is completed are transported directly from outside to the top floor using tower cranes prepared for construction before the ceiling of the reactor building is assembled. An overhead crane, which will be used as lifting equipment for operations on the top floor of the reactor building such as opening and closing the reactor pressure vessel lid during a reactor refueling shutdown, was assembled and made operational. Since then, it has been moved and installed using the overhead crane. For this reason, it is not possible to install large reactor internal structures until after the overhead crane is in operation, and therefore building work above the top floor of the reactor building, installation of the overhead crane, and installation of the reactor internal structure using the overhead crane are required. The installation work formed one of the critical paths of the entire nuclear power plant construction process.

Figure 3 is a cross-sectional view of the reactor building of a conventional boiling water nuclear power plant, in which a concrete plug for shielding 1 and a reactor containment vessel lid 2 are used to open the reactor when the reactor is stopped for refueling. and the top floor of the reactor building (operation floor) for lifting the pressure vessel lid 3, etc.
An overhead crane 5 is installed as a lifting machine for temporarily placing the container on the roof 4. The overhead crane 5 consists of a club 6 whose main part is a lifting device and a girder 8 that runs on a runway 7, and the runway 7 is constructed on a crane column 9.

However, during the construction of the reactor building, the overhead crane 5 is brought in and assembled before the construction of the roof steel frame 11 and the roof 12, which are the ceiling 10, due to the construction procedure and process of the reactor building. Work scaffolding 14 is being erected for the concrete work of the top floor wall 13, which will be constructed in parallel with the assembly of the overhead crane 5 after the construction of the roof steel frame 11.
Therefore, the girder 8 of the overhead crane 5 cannot run, and even if the finishing work on the wall 13 is completed, the work scaffold 1
After roof crane 4 is dismantled, the overhead crane 5 must pass a running test and completion inspection before it can be operated. Therefore, even if the roof steel frame 11 is completed, it will take a long time (3 to 4 (Kezuki) Lifting equipment was not available on the top floor of the reactor building, making it impossible to install large reactor internal structures 17 such as the upper lattice plate, which is one of the reasons for the lengthening of the construction period for the entire nuclear power plant. I was getting used to it.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems. After constructing the roof steel frame of the ceiling of the reactor building, monorails and hoists are attached to the lower part of the reactor building, so that the inside of the reactor is not affected by the walls of the reactor building or other processes. The purpose of the present invention is to provide a construction method for a nuclear reactor building that allows installation work of structures and the like and shortens the construction period of a nuclear power plant.

[Summary of the invention]

The present invention involves the process of constructing a reactor building up to the top floor, and carrying in an overhead crane and internal reactor structures into the reactor building using a tower crane installed outside the reactor building, and then carrying and installing a roof steel frame. The process includes laying a monorail on this roof steel frame and suspending a lifting machine on this monorail, transporting and installing equipment using this lifting machine, and constructing a work scaffold on the top floor in parallel with the construction of the top floor wall. A method of constructing a nuclear reactor building, which comprises a step of carrying out a traveling test of the overhead crane and a completion inspection.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a sectional view of the main parts of the reactor building. The reactor pressure vessel 15 is housed in the reactor containment vessel 16, but during construction work, the reactor internals 17 such as the upper lattice plate were installed. Both the pressure vessel 15 and the reactor containment vessel 16 have their reactor containment vessel lid 2 and pressure vessel lid 3 removed, and are in a state where they are open to the top floor of the reactor building. The ceiling 10 on the top floor of the reactor building has a steel truss structure, and a roof steel frame 11 is constructed between the pillars on the top floor, and a roof 12 is provided above this. A monorail 18 is installed at the lower end of this roof steel frame 11 so as to pass directly above the core of the pressure vessel 15.
A traveling lifting device 19 such as a hoist or chain block is attached to this.

Figure 2 is a plan view of the top floor of the reactor building, where the pressure vessel 15, reactor containment vessel 16, spent fuel storage pool 20, equipment temporary storage pool 21, hatch 22 for loading and unloading equipment, etc. are arranged. .

Next, construction work according to the present invention will be explained. When the reactor building is completed up to the top floor 4, the roof steel frame 1
1. Before constructing the wall 13, install the overhead crane 5, concrete plug 1 for damping, and assembled steam/water separator,
Large and heavy items such as steam dryers and other furnace structures that cannot be brought in until the top floor building is completed will be brought in using a tower crane installed outside (not shown).
The top floor building including the rear wall 13 and roof 12 will be constructed, but the roof steel frame 11 will be constructed using an outdoor tower crane.
The wall 13 is constructed by constructing a work scaffold 14. Regarding the ceiling 10, after assembling the roof steel frame 11, a monorail 18 is laid at the lower end, and a lifting machine 19 is suspended on this monorail 18, and the lifting machine 19 is used to transport the equipment to the top floor 4 or into the temporary equipment storage pool 21. The placed reactor internals 17 and the like are lifted up and installed in the pressure vessel 15, and equipment is carried in and out through the equipment carry-in/out hatch 22. During this time, work scaffolding 14 is erected in the top floor building and construction work on walls 13 and roof 12 is carried out in parallel.

According to the present invention, once the roof steel frame 11 of the reactor building is constructed, even during periods when the overhead crane 5 is not available due to assembly of the overhead crane 5 or construction of the walls 13 on the top floor, the roof steel frame 11 of the reactor building can be constructed without waiting for their completion. Since the lifting and installation work of the reactor internals 17 and the like becomes possible, the construction process for the entire nuclear power plant can be shortened.

The monorail 18 can be left in place even after the overhead crane 5 is completed, and the lifting equipment 18 can be moved to a corner of the building where it does not interfere with the operation of the overhead crane 5. ,
When working with the reactor containment vessel cover 2 or hatch 22 for carrying in and out of equipment, the center position can be determined easily, so it can be used extremely easily for these purposes.

〔Effect of the invention〕

As described above, according to the present invention, during the construction of the top floor of a nuclear power plant building, the construction of the building and the transportation and installation of heavy objects such as reactor internal structures are carried out in parallel using a monorail lifting machine instead of an overhead crane that cannot be operated. This has the effect of efficiently carrying out the construction work of the nuclear power plant building, shortening the construction period and improving economic efficiency.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main parts of the reactor building of the present invention, FIG. 2 is a plan view of the top floor of the reactor building of the present invention, and FIG.
The figure is a cross-sectional view of a conventional reactor building. 5...Ceiling crane, 10...Ceiling, 11...
Roof steel frame, 13...Wall, 14...Work scaffolding, 1
5...Pressure vessel, 16...Reactor containment vessel, 17
...Reactor internal structure, 18...Monorail, 19...
Lifting machine, 22... Hatch for loading and unloading equipment.

Claims (1)

[Claims] 1. The construction process up to the top floor of the reactor building,
A process of transporting an overhead crane and reactor internal structures into the reactor building using a tower crane installed outside the reactor building, then transporting and installing a roof steel frame, and a process of laying a monorail on this roof steel frame and installing a lifting machine on this monorail. a process of suspending the equipment, a process of transporting and installing the equipment using this lifting machine, a process of constructing a working scaffold on the top floor and constructing the top floor wall in parallel, and a process of carrying out a running test of the above-mentioned overhead crane and a completion inspection. A construction method for a nuclear reactor building characterized by comprising the following steps.