JPH0375594A - Fast breeder reactor - Google Patents

Abstract

PURPOSE:To make a reparing device accessible to the entire area of a cold plenum by laying travelling rails for the reparing device, which have its end pat at the barrier wall penetration part of a coolant circulation pump or an intermediate heat exchanger, along the outer circumference of a reactor core support structure. CONSTITUTION:Travelling rails 16 for a reparing device have its one end in the vicinity of a joint between a stand pipe 17 surrounding a coolant circulation pump 9 and a barrier wall 13, and are fixed to the barrier wall 13 through studs 18, along the outer circumference of a reactor support structure 4. When repair work is required in a cold plenum 11 surrounded by a nuclear reactor vessel 1, the barrier wall 13 and the structure 4, the reactor core 3 is removed, for the first place, to drain the whole amount of liquid sodium 2, and then the pump 9 is withdrawn. After that, the reparing device loaded with a manipulator, is suspended through a through-hole in the slab 7, and placed on the rails 16. By running the repairing device on the rails 16 laid on the outer circumference of the structure 4, the manipulator of the repairing device can access to a repairing place through remote control.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a fast breeder reactor, and particularly relates to repairability within the reactor.

(Prior Art) A fast breeder reactor that generally uses liquid metal such as liquid sodium as a coolant has a partition wall that adiabatically separates the inside of the reactor vessel into a high temperature region (hot plenum) and a low temperature region (cold plenum). Multiple intermediate heat exchangers and coolant circulation pumps are mounted on the loop slab that closes off the top of the reactor vessel. These onboard devices penetrate the bulkhead and are installed around the core, and the high-temperature coolant (liquid sodium) that flows from the hot plenum into the intermediate heat exchanger exchanges heat with the secondary coolant. The structure is such that it is cooled and flows out into the cold plenum.

On the other hand, the low-temperature coolant flowing into the coolant circulation pump from the cold plenum flows into the artificial plenum of the core support structure through the reactor piping. The coolant that has flowed into the artificial plenum flows into the reactor core from the high-pressure plenum and flows from the bottom to the top in the core. During this time, the coolant is heated to a high temperature by the nuclear reaction heat of the fuel, flows out from the upper part of the core to the hot plenum, and circulates through the above-mentioned flow path.

(Problem to be solved by the invention) By the way, in such a fast breeder reactor, sufficient design margin is provided to prevent damage to core support structures, bulkheads, and other reactor internal structures, and the design is designed to minimize the possibility of damage occurring. However, in the unlikely event that repairs are required in the cold plenum, it is possible to pull out installed equipment such as intermediate heat exchangers and coolant circulation pumps, and access the repair area through through holes in the loop slab and bulkhead. I will try to figure it out. In this case, various repair devices can be considered, but for example, if a manipulator is attached to a rod-shaped column, there is a limit to the length of the manipulator, and it is structurally difficult to access all areas within the cold plenum. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of these problems, and is to provide a fast breeder reactor that allows repair equipment to approach all areas within the cold plenum.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention includes a reactor vessel containing a coolant, and a nuclear reactor vessel installed within the reactor vessel via a core support structure. a bulkhead that adiabatically separates the inside of the reactor vessel into a high-temperature region and a low-temperature region; a loop slab that closes off the upper part of the reactor vessel; In a fast breeder reactor having a plurality of coolant circulation pumps and intermediate heat exchangers disposed around the reactor, a repair device for running has an end at a partition wall penetrating portion of the coolant circulation pump or the intermediate heat exchanger. Rails are laid along the outer periphery of the core support structure.

(Function) That is, the present invention installs a repair device running rail having an end at the partition wall penetrating portion of the coolant circulation pump or the intermediate heat exchanger along the outer periphery of the core support structure. The repair equipment can run on rails provided along the outer periphery of the core support structure, allowing the repair equipment to approach all areas within the cold brenum.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

1 to 3 show one embodiment of the present invention, and FIG. 1 shows a schematic configuration of a fast breeder reactor. In the figure, a reactor vessel 1 contains liquid sodium 2 as a coolant, and a reactor core 3 is installed on a core support structure 4. The core support structure 4 is bolted onto a core support skirt 5 welded to the bottom of the reactor vessel 1, and an artificial plenum 6 is formed around the outer periphery of the core support structure 4.

On the other hand, a loop slab 7 is installed at the top of the reactor vessel 1, and the loop slab 7 hermetically closes the upper opening of the reactor vessel 1. A plurality of intermediate heat exchangers 8 and a coolant circulation pump 9 are disposed on the loop slab 7.
is installed.

These intermediate heat exchanger 8 and coolant circulation pump 9 are
The reactor core 3 penetrates through partition walls 12 and 13 that adiabaticly separate the inside of the reactor vessel 1 into a hot plenum 10 and a cold plenum 11.
The furnace piping 14 is connected to the discharge port of the coolant circulation pump 9 . This furnace piping 14
is connected to the inlet plenum 6, and the low temperature liquid sodium 2 flowing into the coolant circulation pump 9 from the cold plenum 11 flows into the inlet plenum 6 through the furnace piping 14.

Also, inside the artificial plenum 6, there is a high pressure plenum 15.
The liquid sodium 2 that has flowed into the artificial plenum 6 flows into the reactor core 3 from the high-pressure plenum 15 and flows within the reactor core 3 from below to above. During this time, the liquid sodium 2 is heated to a high temperature by the nuclear reaction heat of the core fuel (not shown), and is passed from the top of the core 3 to the hot plenum 1.
It is designed to flow out to 0. The high-temperature liquid sodium 2 flowing out from the upper part of the core 3 into the hot plenum 10 flows into the intermediate heat exchanger 8, where it exchanges heat with the secondary coolant, and then flows out into the cold plenum 11. It has become.

Furthermore, inside the reactor vessel 1, there is a rail 1 for running the repair equipment.
6 is provided. This repair equipment running rail 16 has one end near the joint between the stand pipe 17 provided around the coolant circulation pump 9 and the bulkhead 13, and has a stud 18 along the outer periphery of the core support structure 4 to form the bulkhead. 13
is attached to the wall.

In such a configuration, if a situation that requires repair occurs in the space surrounded by the reactor vessel 1, bulkhead 13, and core support structure 4, that is, within the cold plenum 11, the reactor core 3 is first removed and The entire limb sodium 2 is drained, and the coolant circulation pump 9 is pulled out. Then, by suspending a repair device (not shown) equipped with a manipulator from the through hole of the loop slab 7 and digging it into the repair device traveling rail 16, the repair device is moved along the outer periphery of the core support structure 4. The repair device can run on the provided repair device running rails 16. therefore,
In this embodiment, even if a situation requiring repair occurs within the cold blemish 11, the manipulator of the repair device can be brought close to the repair location by remote control.

In the above embodiment, the end of the repair equipment running rail 16 was provided near the partition wall penetration part of the coolant circulation pump 9, but the repair equipment running rail 16 was provided with an end near the partition wall penetration part of the intermediate heat exchanger 8. A section may be provided.

[Effects of the Invention] As explained above, the present invention provides a reactor vessel containing a coolant, a reactor core installed in the reactor vessel via a core support structure, and a reactor vessel that is heated to high temperatures. A bulkhead that insulates and separates the reactor vessel from the low-temperature zone, a loop slab that closes off the upper part of the reactor vessel, and a plurality of coolant units that are mounted on the loop slab, penetrate the bulkhead, and are arranged around the reactor core. In a fast breeder reactor having a circulation pump and an intermediate heat exchanger, a repair device running rail having an end at a partition wall penetration portion of the coolant circulation pump or the intermediate heat exchanger is provided along the outer periphery of the core support structure. It was installed by

Therefore, when a situation requiring repair occurs in the cold plenum, the repair equipment can be run on the rails for running the repair equipment installed along the outer periphery of the core support structure. Since it becomes possible to approach all areas within the cold plenum, repairability within the furnace can be improved.

[Brief explanation of drawings]

1 to 3 show one embodiment of the present invention, FIG. 1 is a schematic diagram of a fast breeder reactor, and FIG. 2 is a development of the rail for running the repair equipment as seen from the direction of the arrow shown in FIG. 1. 3 are detailed views showing section A in FIG. 1. 1... Reactor vessel, 2... Liquid sodium, 3...
- Core, 4... Core support structure, 5... Core support skirt, 6... Population plenum, 7... Loop slab, 8... Intermediate heat exchanger, 9... Coolant circulation pump,
10... Hot plenum, 11... Cold plenum, 12.13... Partition wall, 14... Furnace piping, 15
...High pressure plenum, 16...Repair equipment running rail.

Claims (1)

[Claims] A reactor vessel containing a coolant, a reactor core installed in the reactor vessel via a core support structure, a partition wall that adiabatically separates the interior of the reactor vessel into a high temperature region and a low temperature region, and the reactor In a fast breeder reactor that has a loop slab that closes the upper part of the vessel, and a plurality of coolant circulation pumps and intermediate heat exchangers that are mounted on the loop slab and are arranged around the reactor core passing through the partition wall. A fast breeder reactor, characterized in that a repair device running rail having an end at a partition wall penetration portion of the coolant circulation pump or the intermediate heat exchanger is laid along the outer periphery of the core support structure.