JPS5937497A - Nuclear fuel transporting facility - 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 The present invention relates to a fuel transfer facility for transferring new fuel and spent fuel between a reactor vessel and an extra-core fuel storage tank in a liquid metal cooled fast breeder reactor.

The above mentioned fuel transfer equipment is used for fuel exchange in N sub-reactors, and in order to improve the operating rate of the reactor, it must be possible to transfer fuel efficiently in the shortest possible time and its handling. It is desirable that maintenance and inspection can be easily performed.

In this type of equipment, fuel is taken in and out of the 9M sub-reactor vessel and the extra-core fuel storage tank (hereinafter referred to as 1"EVSTJ) using an inclined chute method, and a fuel transfer cell is connected between the two vessels, and inside this cell Conventionally known systems have been known in which spent fuel and new fuel taken out of the reactor core are put into fuel packets and transferred between the reactor vessel and the EVST through chutes by running a fuel transfer machine. By using the slope type chute in this way, the fuel exchange machine inside the reactor vessel, which handles fuel by hanging vertically, and the above-mentioned fuel transfer machine do not interfere with each other, and the packets can be easily handled. Therefore, the fuel relay device inside the reactor that was used in the previous system can be omitted, which has the advantage of simplifying the equipment.However, on the other hand, the fuel transfer as mentioned above The method of transferring fuel inside the cell has the following disadvantages: The inside of the fuel transfer cell is communicated with the inside of the reactor vessel through a chute, and the radiation used as secondary coolant is The cell is a radioactively contaminated area due to dripping accumulation of oxidized sodium and infiltration of the cover gas from inside the reactor.For this reason, the cell has sufficient airtightness and is equipped with sufficient airtightness to prevent spent fuel and the above radioactivity. Jahei function is required.

As a result, the cell becomes a large, heavy structure made of thick, heavy concrete, and there are also problems with earthquake resistance, resulting in extremely high equipment costs. In addition, since maintenance personnel are not allowed to enter the cell, maintenance and inspection of the transfer machine installed inside the cell and its attached equipment, etc.

All repairs must be performed inside the cell by remote control from the outside using a manipulator or the like, resulting in poor maintainability.

This invention has been made in view of the above points,
The purpose is to provide a new fuel transfer facility that eliminates the drawbacks of the conventional inclined chute cell system, has low equipment costs, and allows easy maintenance such as maintenance and inspection of component equipment.

The configuration and operation of the present invention will be described in detail below based on illustrated embodiments.

First, an overview of the entire equipment will be described with reference to Figures 1 and 2. In the figure, l is a steel reactor containment vessel, 2 is a reactor vessel installed under the floor of the containment vessel 1, 3 is a reactor core, and 4
6 is a fuel exchanger installed on the rotary plug 5 of the reactor vessel, and 6 is an ex-core fuel storage tank (ST) installed outside the containment vessel 1.

Reference numeral 7 indicates a fuel storage rack installed in the tank, and reference numeral 8 indicates the fuel handling machine. The nuclear reactor facilities up to this point are the same as conventional ones.

Now, according to the present invention, as a fuel inlet/outlet passage extending between the inside and outside of the reactor vessel 2 and the EVST 6, firstly, the passage between the containment vessel 1 and the reactor vessel 2, and between the containment vessel and the FiVST 6.
There are constructed ramp-type fuel inlet/output chutes 9 and 10, each of which has an upper end boat that independently opens onto the floor surface of the containment vessel. Of these, chute 9 penetrates the fixed plug of reactor vessel 2.

One chute (10) is configured to penetrate the tank wall ring of the EVST 6 and the containment vessel (1) and open onto the floor, and each shoe (9)
．． A floor door valve 11j12 is connected to the upper end boat 10. Incidentally, for the chute 10, a flexible body 13 is constructed to surround the chute. On the other hand, inside the containment vessel l, there is a fuel transfer path l connecting the chute 9 and the boat lO mentioned above.
A traveling rail 14 is laid along this line.

A traveling trolley type fuel transfer machine 15, the detailed structure of which will be described later, is disposed on this rail. Along the running route of the nuclear fuel transfer device 15, a pit for maintenance and inspection of the transfer structure, indicated by reference numeral 16, and a bit for separating the fuel storage packet, indicated by reference numeral 17, are constructed under the floor. .

Next, as shown in Figures 3 to 6, the one-truck type fuel transfer machine 15
The detailed structure of is explained below. That is, the transfer machine 15 is
A closed coffin 18 is mounted on a self-propelled cart 16 that runs on a traveling rail 14, and the coffin has a door valve 19 at its lower end and a fuel storage packet as described below at its top for lifting and lowering operations. A fuel storage packet 21 is suspended from the drive unit 20 via a chain or tape 20A, and is housed in the coffin. As shown in the figure, the fine 58 is surrounded by a shield 18A of sufficient thickness.

In addition, the packet 21 is composed of two fuel storage pots 21A and 21B with open tops, and wheels 2IC are provided above and below the fuel storage pots 21A and 21B. Guide supported. On the other hand, as shown in FIGS. 3 and 7, the fuel inlet/outlet chute 9 is provided with a guide rail 9A that guides the packet 21 along its slope. Note that 9B is a cylindrical body. This structure is the shoe on the EVST side)1
The same applies to 0. In addition, as shown in FIG. 8, there are four fuel relay racks 23A to 4 in parallel with the end of the chute 9 along the movement locus 22 of the refueling machine in the reactor vessel.
23D is deployed.

Next, the fuel transfer operation ζ in the equipment with the above configuration will be described. First, move the fuel transfer device 15 to the EVST T side chute 1.
0 to the upper end boat position, and here door pulp 19 and 1
2 is connected and opened, and in this state, the packet 21 is suspended into the tank of the EVST 6 through the shoe 10. Here, the fuel handling machine 8 is driven, and the new fuel that has been brought into the EVST in advance is loaded into the two cylinders (1-21) 21A.
, 21B. During this time, on the reactor vessel side, the fuel exchanger 4 is driven to pull out the spent fuel from the reactor core 3.
They are inserted into the relay chics 23A and 23D in the furnace shown in FIG. 8 as indicated by black circles 27 and are on standby, ready for transport outside the furnace. Next, on the l1iVST side.

The bucket) 21 containing fresh fuel is pulled up through the chute 10 into the coffin 18 of the transfer machine 15, and the door pulps 19 and 12 are closed, and the connection between them is severed. Next, the transfer machine 15 is run on the rail i4 and
Move to the chute 9 position on the opposite side, connect the door pulps 19 and 11 at this position, and then open it. Then, shoot the packet 21 containing the new fuel!・Hang down inside 9,
When it reaches the end, operate the fuel exchanger 4 and pour new fuel 28 into the pots 21A and 21B of the packet 21 as shown by the arrows (A) and (1:I) in Figure 8.
Transfer the spent fuel 27 from the racks 23A and 23D to the in-furnace relay racks 23B and 23C as shown by the arrows ) and ←) in the empty packet bottles.
Insert 21A and 21DJ. Once this work is completed,
Immediately, the packet 21 is hoisted up and stored in the coffin 58 of the transfer machine 15, and the doorknobs (lubs 19 and 11 are closed to separate the two).Then, the transfer machine 15 is moved to the EVST again.
Move to the chute 10 on the side, connect the door pulps 19 and 12, and then feed the packet 21 through the shoe 10.
The spent fuel is suspended into the VST tank and then transferred from the packet 21 to the storage rack 7 by operating the fuel handling machine 8. During this time, on the reactor side, the fuel exchanger 4 takes out new fuel from the racks 23B and 23C and loads it into the reactor core 3. This completes one cycle of fuel transfer, and the same cycle is repeated to perform fuel exchange while transferring a large amount of new fuel and spent fuel between EVST 6 and reactor vessel 2. . In addition, it is also possible to transfer fuel one by one by setting one of the two pots in the fuel bucket (21) exclusively for new fuel and the other exclusively for spent fuel. According to this method, there are no in-reactor racks 23A to 23D. You can.

Next, the method of maintenance and inspection of the main body of the fuel transfer device 15 and the fuel nozzle 9-21 will be explained.The detailed structure of the two bits 16 and 17 shown in Figs.
As shown in the figure, the packet separating bit 17 in particular is equipped with a floor door pulp 17A on its upper part, and furthermore a packet separating device 24 and a packet accommodation cask 25 inside the bit, and the cask 25 is provided as necessary. It is designed to accommodate the bucket) 21 and transport it to an external maintenance facility. In addition, maintenance personnel can directly enter the inspection pit (16) for the main body of the transfer machine, and the inside of the bit (for cleaning the door pulp 19)
It is equipped with maintenance equipment 26 necessary for disassembly and inspection. Maintenance and inspection of the transfer machine 15 is carried out by first moving the transfer machine 5 directly above the bit 17, and with the door pulp 19 and 17A connected, the packet 21 containing sodium is transferred to the cask 2.
5, then bucket l-21,! : Separate from the hanging tape 20. Next, pick the transfer machine 15)1
6, and after thoroughly cleaning the main body of the transfer machine, the door pulp 19 and the like are disassembled and inspected. This work should be carried out directly by maintenance personnel.

As described above, according to the present invention, the fuel transfer equipment is constructed by combining the inclined fuel inlet/output chute and the traveling trolley type fuel transfer machine equipped with a coffin. Not only can fuel be fully utilized and efficiently loaded and transferred in a short period of time, but on the other hand, there is no need for a conventional large, heavy-structured fuel transfer cell, resulting in lower equipment costs. Furthermore, maintenance work on the fuel transfer machine, which requires frequent maintenance and inspection, can be performed directly by approaching the fuel transfer machine, rather than by remote control of a manual operator as in the past, which improves maintenance efficiency. Effects such as significant improvements can be obtained.

[Brief explanation of drawings]

Each figure shows an embodiment of the present invention. Figure 1 is a configuration diagram showing an outline of the entire equipment, Figure 2 is a partial plan view of Figure 1, and Figure 3 shows a fuel transfer machine and an atom. A vertical cross-sectional view showing the detailed structure of the chute on the reactor vessel side, Fig. 4 is a front external view of the fuel transfer device, Fig. 5 is a cross-sectional view taken along arrow v-■ in Fig. 3, and Fig. 6
The figure is a front external view of the fuel packet, Figure 7 is a sectional view taken along the arrow ■-■ in Figure 3, Figure 8 is an explanatory diagram of the operation of fuel transfer in the reactor, and Figure 9 is a maintenance and inspection of the fuel transfer machine. FIG. l...Reactor containment vessel, 2...Reactor vessel, 3...
- Core, 4... Fuel exchange machine, 6... Ex-core fuel storage tank, 7... Fuel storage rack, 8... Fuel handling machine, 9.
10... Slope type fuel inlet/out shoe), 11.12...
Floor door pulp, 14... Traveling rail, 15... Traveling trolley type fuel transfer machine, 16... Pit for maintenance and inspection of fuel transfer machine body. 17...Fuel packet separation bit, 18...Coffin, 19...Door pulp, 20...Packet lifter 4 doctor, 5 Figure 76 Figure 1

Claims (1)

[Scope of Claims] l) A slope type structure in which an upper end boat is opened above the floor surface of the reactor containment vessel and is connected to the reactor vessel and the external fuel storage tank below the floor surface. a fuel inlet/output chute, a floor door valve installed on the upper end boat of each chute, and a running rail laid on the floor surface of the containment vessel along a fuel transfer path connecting the boats of both chutes; The fuel packet includes a fuel packet, a packet lifting/lowering drive mechanism for lifting and lowering the packet by suspending the packet with a chain or tape, and a traveling trolley type fuel transfer machine for mounting a coffin equipped with a door pulp on a traveling trolley and traveling on the rail, Fuel transfer equipment for a nuclear reactor, characterized in that new fuel and spent fuel are transferred between a reactor vessel and an external fuel storage tank by operating a fuel transfer device. 2. In the fuel transfer equipment according to claim 1, the fuel packet is composed of a plurality of fuel pots each storing one bottle of fuel. 4! This is a characteristic nuclear reactor fuel transfer facility. 3) I\j#v-In the fuel transfer equipment according to claim 1, along the travel route of the traveling trolley type fuel transfer machine,
1. Fuel transfer equipment for a nuclear reactor, comprising a bit for separating fuel packets and a bit for maintenance and inspection of a fuel transfer device body under the floor of a containment vessel.