JP2501222B2 - Refueling equipment - Google Patents

Description

The present invention relates to a hot cell type fuel exchange facility for a fast breeder reactor, and particularly to a fuel exchange facility suitable for reducing the upper space of the reactor and preventing scattering of sodium mist in the reactor. Regarding

[Conventional technology]

FASt breeder systems: Experience Gain is a conventional hot cell refueling facility for fast breeder reactors.
ed and Path to Economical Power Generation, Septemb
er 13-17, 1987, PP 9.5-1 to 9.5-6, and the structure thereof is shown in FIG. In this figure, 1 is a core, and a fuel pot 2 is installed on the outer periphery of the core 1. An opening 4 communicating with the furnace upper chamber 3 is formed in the furnace upper part, and the furnace upper mechanism, that is, UIS (upper internal
structure) 5 is located. A UIS lifting device 6 is installed above the upper furnace mechanism 5 in the upper furnace chamber 3, and a crane-type fuel exchanger 7 is arranged in the upper furnace chamber 3.

At the time of refueling, after the operation was stopped,
The UIS hoisting device 6 hoists to open the opening 4 at the top of the furnace. Next, the crane type fuel exchanger 7 is moved to the vicinity of the opening 4, the fuel exchanger 7 is inserted from the opening 4, and the fuel in the core 1 is moved or moved to the fuel pot 2. The fuel transferred to the fuel pot 2 is taken out through the furnace upper opening 4, passes through the furnace upper chamber 3, and is transported to the fuel storage facility.

[Problems to be Solved by the Invention]

In this conventional equipment, refueling is performed by a crane-type refueling machine 7 that is vertically lowered from the upper opening 4 of the furnace.
Therefore, the diameter of the reactor upper opening 4 needs to be as large as the diameter of the core 1 plus the diameter of the fuel pot 2 installed outside thereof. Therefore, the opening area of the opening 4 becomes large, and there is a problem that sodium mist in the furnace is scattered from the opening 4 to the furnace upper chamber 3 at the time of refueling.

Further, since the crane-type refueling machine 7 has a wide movable range, the furnace upper chamber 3 needs to have a size commensurate with the movable range, the space of the furnace upper chamber 3 becomes large, and at the time of refueling, the opening 4 is Since the furnace upper mechanism 5 that is lifted is located above, there is a problem that it is difficult to perform fuel exchange by the crane type fuel exchanger 7.

The object of the present invention is to suppress the scattering of sodium mist,
An object of the present invention is to provide a fuel exchange facility capable of smoothly performing fuel exchange within a limited space in the upper chamber of the furnace.

[Means for solving the problem]

The above-mentioned object is to install a traveling rail in the upper chamber of the furnace and to have a fuel holding portion supported on the traveling rail by a laterally and longitudinally expandable / contractible supporting means, and also serves as a fuel exchanger and a fuel inlet / outlet unit. This is achieved by a fuel exchange facility in which the refueling device is movably mounted and the traveling rail is configured such that a portion located above the furnace opening is extendable with respect to other portions.

The upper furnace chamber is preferably provided in an upper portion of the upper furnace chamber, and has a storage space in which the upper furnace mechanism including a control rod drive mechanism is lifted and stored at the time of refueling. An openable and closable sodium saucer is provided adjacent to the storage space to vertically partition the storage space from the other parts of the furnace upper chamber.

(Operation) The fuel exchange device on the traveling rail installed in the furnace upper chamber moves on the rail to exchange fuel. At this time, the fuel exchange device extends the supporting means in the vertical direction to lower the fuel holding portion into the reactor from the opening in the upper part of the furnace, and extends the supporting means in the lateral direction to move the fuel holding portion over the required range of the core. . As a result, the furnace upper opening can be made smaller. Since the furnace upper opening can be made smaller in this way, it is possible to reduce the scattering of sodium mist from the furnace to the furnace upper chamber. Further, since the traveling rail for moving the refueling device is configured such that the upper portion of the furnace opening can be extended with respect to other portions, for example, the traveling rail is extended while traveling during refueling. By configuring the rail, it is possible to effectively utilize the limited space in the upper chamber of the furnace and smoothly perform fuel exchange.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, 10 is the core of the fast breeder reactor,
10 is arranged in the center of the reactor vessel 11, and a fuel pot 12 is arranged on the outer periphery of the core 10. The upper part of the core 10 is equipped with a reactor control rod drive mechanism, that is, UIS (upper interna
l structure) 13 is located, and the furnace upper part mechanism 13 is arranged in an opening 15 having a relatively small diameter that communicates with the furnace upper chamber, that is, the cell chamber 14. A traveling rail 16 is installed in the cell chamber 14, and on the traveling rail 16, a fuel exchanging device 17 which also serves as a fuel exchanging machine and a fuel ejecting machine is movably mounted on the traveling rail 16 as described later.

The traveling rail 16 is configured such that a portion located above the furnace opening portion 15 can be extended with respect to other portions in order to enable the upper furnace mechanism 13 to be lifted. Specifically, for example, it can be configured as shown in FIGS. 2 to 4. That is, the traveling rail 16 is composed of a fixed rail 21 fixed to the building 20 and a movable rail 22 movable in the longitudinal direction with respect to the fixed rail 21, and the movable rail 22 is usually shown in FIG. As described above, the fixed rail 21 is made to stand by at the lower retracted position. At this position, the tip of the moving rail 22 is the rail support
Supported by 23. The rail support 23 is provided with height adjusting means 24 (see FIG. 4) such as a fluid cylinder. In this state, after lifting the furnace upper part mechanism 13, the rail pedestal attached to the building 20 with the moving rail 22 facing the fixed rail 21.
It is extruded toward 25, and the tip of the moving rail 22 is placed on the pedestal 25 as shown in FIG. Next, the height adjusting means 24 of the rail support 23 adjusts the height of the rear end of the moving rail 22,
Combined linearly with the tip of the fixed rail 21 and fixed integrally.

A storage space for arranging the furnace upper part mechanism 13 lifted at the time of refueling in the upper part of the furnace upper part mechanism 13 of the cell chamber 14 at the upper part of the furnace.
A UIS lifting device 31 is installed on the ceiling of the storage space 30. Further, on the ceiling of the cell chamber 14 near the lower end position of the storage space 30, an openable and closable sodium tray 32 is provided in the lower part of the storage space 30, and when the fuel is exchanged, the storage space 30 and other parts of the cell chamber 14 are The tray 32 is vertically partitioned.

As shown in FIGS. 5 and 6, the fuel exchange device 17 is
The bogie part 40 placed on the traveling rail 16 and the bogie part 40
The fuel handling part 41 and the fuel handling part
Reference numeral 41 denotes a link-type telescopic arm 43 that supports the fuel holding portion, that is, the gripper 42 so as to be capable of laterally telescoping, and the telescopic arm 43.
And a telescopic tube portion 44 for supporting the telescopically in the vertical direction. The gripper 42 is a tubular body 43A that forms a part of the telescopic arm 43.
Is inserted into the upper end of the gripper 42 and is linked to a gripper arm 45 for operating the gripper 42. Telescopic arm 43
It is connected to an arm moving shaft 46 as shown in FIGS. 7 and 8 and is operated by moving the arm moving shaft 46 up and down. The fuel handling portion 41 also has a case 47 for accommodating the telescopic arm 43 and the telescopic tube portion 44 together with the gripper 42 and the fuel in the contracted state.

When the refueling device is moved, as shown in FIGS. 5 and 7, the telescopic arm 43 is contracted, and the telescopic arm 43, the gripper 42, and the gripper arm 45 are housed in the lowermost cover 44A of the telescopic tube portion 44. Then, by contracting the expansion / contraction tubular portion 44, the contraction tubular portion 44 is housed in the case 47 together with the members. At the time of refueling, as shown in FIGS. 6 and 8,
Extend the telescopic tube arm 43 and telescopic tube section 44 to
42 and the gripper arm 45 are taken out laterally from the telescopic tube portion 44 to perform fuel exchange.

A sodium saucer 50 is provided at the lower open end of the case 47 so that it can be opened and closed, and a sodium drain line 51 and a vapor trap pipe 52 are connected to the lower part of the case 47. It is connected to the device 53 and the vapor trap 54. The sodium pan 50 is open when refueling, and the sodium pan 50 is closed when the refueling device is moved.
It functions as a saucer for sodium dripping with a gripper etc. stored in 47. The sodium accumulated in the tray 50 is removed by the suction device 53 via the sodium drain line 51. The sodium paper in the case 47 is also removed by the vapor trap 54 via the vapor trap pipe 52.

An example of the structure of the gripper 42 is shown in FIG. here,
The gripper 42 includes a gripper cylinder 60, a gripper shaft 61 that moves up and down in the gripper cylinder 60, and is pivotally attached to the gripper cylinder 60 with a pin 62. It comprises a support 65 which is moved by 64. The gripper cylinder 60 is inserted into the upper end of the arm cylinder portion 43A described above, and the gripper shaft 61 is associated with the gripper arm 45 described above. A groove 67 is formed on the inner circumference of the upper end of the fuel rod or fuel pot 66, into which the tip of the support member 64 projects.

When gripping the fuel rod or fuel pot 66, the gripper arm 45 is operated to move the gripper shaft 61 to the position shown in the figure, and the support tool 65 is pushed from the inside by the large-diameter portion 63 of the tip of the gripper shaft 61. Hook the tip of the support tool 65 into the groove 67 of the fuel rod or fuel pot 66. When removing the fuel rod or the fuel pot 66, move the gripper shaft 61 downward to move the rear large diameter portion 64.
Pushes the rear projection of the support tool 65 inside the gripper body to move the tip of the support tool inward and bring the tip of the support tool out of the groove 67. In this way, the fuel rod or the fuel port 66 can be gripped and opened by operating the gripper shaft 61 up and down.

Actually, since the diameter of the fuel rod is different from that of the fuel pot, the gripper 42 should have a diameter corresponding to each diameter.
Two sets of telescopic arms 43 and gripper arms 45 are similarly prepared.

The spent fuel transfer route in which the fuel exchange facility of this embodiment is arranged will be described with reference to FIG.

The fuel is taken out from the core 10 by the fuel exchange device 17, inserted into the fuel pot 12 at the outer peripheral position of the core, taken out together with the fuel pot 12 to the canning equipment 70. Refueling device 17
Also serves to transfer the new fuel in the fuel pot into the reactor.

In the canning equipment 70, the fuel pot 12 in which the fuel is inserted is covered. The canned fuel is taken out by the in-cell crane 71, and the canned fuel is cooled by gas and transferred to the spent fuel underground cart 72. The spent fuel transfer crane 73 lifts fuel from the spent fuel underground truck 72 and installs it in the spent fuel storage facility 74.

Next, the procedure for refueling by the refueling facility of this embodiment will be described with reference to FIGS. 11 (A) to 11 (D).

UIS to prepare for lifting the upper furnace mechanism 13 after operation stop
The lifting device 31 is attached to the furnace upper mechanism 13. In addition, while replacing the inside of the cell chamber 14 in the upper part of the furnace with nitrogen gas, in order to reduce the specific gravity of nitrogen gas and to prevent sodium mist from reaching the melting temperature and adhering to the cell chamber wall surface, the temperature inside the cell chamber is operated. From about 50 ℃ to about 150 ℃.

Next, as shown in FIG. 11 (A), the UIS lifting device 31
The upper furnace mechanism 13 is lifted by means of a UIS fixing device (not shown), and the upper furnace mechanism 13 is fixed in the storage space 30 of the cell chamber 14 so that there is no problem in terms of earthquake resistance.

In addition, the moving rail 22 of the traveling rail 16 is extended to the upper part of the furnace and installed (see FIG. 4), and the sodium tray 32 is placed at the lower part of the upper part of the furnace 13 so that sodium adhering to the upper part of the furnace 13 does not drip onto the upper part of the furnace. To install. The sodium tray 32 also serves as a seal function between the space 30 for accommodating the furnace upper part mechanism 13 in the furnace upper cell chamber 14 and the other part. That is, the storage space 30 of the furnace upper mechanism 13 is set at 150 ° C as described above.
Since the amount is set to about, sodium adhering to the furnace upper part mechanism 13 or the like becomes sodium mist and scatters in the cell chamber 14, and may adhere to electric parts such as CRDM. By installing the sodium saucer 32, the storage space 30 can be
It is possible to prevent the sodium mist from scattering into the cell chamber 14 by keeping it isolated from 14, and to keep the temperature in the storage space 30 as low as about 50 ° C. during operation to reduce the generation of sodium mist itself.

On the other hand, since the nitrogen gas in the furnace upper cell chamber 14 has a high temperature of about 150 ° C., the sodium mist in the cell chamber 14 becomes higher than the melting temperature and is prevented from adhering to the cell chamber wall surface. Further, nitrogen gas has a low specific gravity, but the specific gravity is further reduced by heating the light nitrogen gas having a low specific gravity to a high temperature of 150 ° C. The nitrogen gas having a low specific gravity covers the furnace upper opening 15,
Sodium mist is prevented from flowing into the cell chamber 14 from the inside of the furnace through the opening 15. In order to prevent the nitrogen gas atmosphere from flowing into the furnace vessel 11, a slight amount of Ar gas is purged in the furnace.

Next, as shown in FIG. 11 (B), the fuel exchange device 17 is moved above the furnace upper opening 15, and the telescopic cylinder portion 44 of the fuel exchange device 17 is extended and its tip is lowered, so that the telescopic arm is extended. 43 is stretched laterally (see Figures 5 and 6). Core 10
Since the fuel of (1) is taken out of the reactor directly by the fuel exchange device 17, the in-reactor storage facility is not provided. First of all,
As shown in FIG. 11 (C), the gripper 42 of the fuel exchange device 17
Thus, the core 10 is pulled out from a predetermined position and inserted into the pot 12 installed on the outer periphery of the core. Next, as shown in FIG. 11 (D), the fuel is taken out of the furnace together with the pot 12 by the same fuel exchange device 17. As described above, the fuel exchange device 17 is provided with the sodium tray 50 for receiving the sodium dropped from the pot 12 and the sodium drain line 51. The pot 12 containing fuel is a refueling device.
While being cooled by the nitrogen gas cooling system provided in 17,
It is carried out to the above-mentioned fuel canning facility 70 (see FIG. 10).
The sodium mist that comes out in the cooling nitrogen gas is charged into the upper chamber of the furnace.
It is removed by the vapor trap pipe 52 and the vapor trap 54 so as not to be released into the inside 14.

The new fuel is put in the fuel pot 12 and is first inserted into the position of the pot 12 in the furnace by the fuel exchange device 17. Next, the fuel is grabbed by the same fuel exchange device 17, taken out from the pot 12, and inserted into a predetermined position in the furnace.

As described above, the fuel exchange device 17 moves on the traveling rail 16 to carry out the fuel from the upper part of the core to the canning facility, and also carry in the new fuel into the reactor, thereby serving as an in-cell crane.

When the above fuel exchange is completed, the upper furnace mechanism 13 is restored in the reverse procedure from the operation stop to the fuel exchange.

In this manner, the fuel exchange device 17 takes in and out the fuel and exchanges the fuel by the support means 43 and 44 that can be expanded and contracted in the vertical and horizontal directions, and at the time of movement, the support means, the gripper 42, etc. are housed in the case 47. Move in a compact form. As a result, the furnace upper opening 15 can be made smaller as shown in FIG. 1 and the like, and the scattering of sodium mist from the furnace to the furnace upper chamber 14 can be reduced. Therefore, in combination with the use of nitrogen gas and the temperature increase thereof, it is possible to effectively prevent the sodium mist in the furnace vessel 11 from scattering into the furnace upper chamber 14. In addition, the traveling rail 16 has a furnace opening.
Since the portion located above 15 is configured to be extendable with respect to other portions, for example, the traveling rail 16 can be configured by extending what was normally folded at the time of refueling. The fuel exchange device 17 moves on the traveling rail 16 to perform the fuel exchange, and the gripper 42 and the like are housed and moved in the case 47 so that the limited space of the upper furnace chamber 14 can be effectively used. It can be used for smooth refueling.

〔The invention's effect〕

As is clear from the above, according to the present invention, it is possible to prevent the sodium mist from scattering due to the reduction of the furnace upper opening.
Further, the compact fuel exchange device moves on the traveling rail having the extendable structure to perform the fuel exchange, so that the limited space can be effectively utilized and the smooth fuel exchange can be performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a fast breeder reactor including a fuel exchange facility according to an embodiment of the present invention, FIG. 2 is a top view of a traveling rail of the fuel exchange facility, and FIG. FIG. 4 is a side view, FIG. 4 is a side view showing an extended state of the traveling rail, FIG. 5 is a partial cross-sectional side view of a fuel exchange device of the fuel exchange facility, and FIG. FIG. 7 is a partial cross-sectional side view showing an extended state of the supporting means of the device, FIG. 7 is a cross-sectional view of the lower end of the fuel handling portion in the fuel exchange device shown in FIG. 5, and FIG. 8 is a fuel exchange in FIG. FIG. 9 is a sectional view of a lower end of a fuel handling portion in the apparatus, FIG. 9 is a sectional view of a gripper of the fuel handling portion, and FIG. 10 is a diagram showing a fuel transfer route in which the fuel exchange equipment of the present invention is arranged. , FIG. 11 (A) to FIG. 11 (D) show the fuel exchange by the above fuel exchange facility. Procedure is a process diagram showing a FIG. 12 is a sectional view of the reactor of a conventional refueling facilities. Explanation of symbols 10 …… Reactor core, 12 …… Fuel pot 13 …… Reactor upper mechanism 14 …… Reactor upper chamber (cell chamber) 15 …… Opening, 16 …… Traveling rail 17 …… Refueling device 22 …… Moving Rail (extendable part) 30 …… Storing space, 32 …… Sodium saucer 42 …… Gripper (fuel holding part) 43 …… Extensible arm (supporting means) 44 …… Extensible cylinder part (supporting means) 47 …… Case

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuji Motonaga, 3-1-1, Saiwaicho, Hitachi, Ibaraki Hitachi Ltd., Hitachi Works (56) References JP-A-55-54495 (JP, A) Actually open 60-152999 (JP, U) Actually open 58-156298 (JP, U) Actually open 58-104998 (JP, U) Actually open 57-112294 (JP, U)

Claims (2)

(57) [Claims] 1. In a hot cell type fuel exchange facility for a fast breeder reactor, a traveling rail is installed in the upper chamber of the reactor, and a fuel holder supported on the traveling rail by a supporting means that is capable of expanding and contracting in the horizontal and vertical directions. A refueling device that has a portion and serves both as a refueling machine and a fuel in-and-out machine, and is movably mounted, and
A fuel exchange facility, wherein the traveling rail is configured such that a portion located above the furnace opening portion can be extended with respect to other portions. 2. The furnace upper chamber has a storage space which is provided in an upper portion of the furnace upper chamber and in which a furnace upper mechanism having a control rod drive mechanism is lifted and stored at the time of refueling. 2. The refueling facility according to claim 1, further comprising an openable / closable sodium tray provided in the vicinity of the lower end of the space to vertically partition the storage space from the other part of the furnace upper chamber.