JP3079771B2 - Fast Breeder Refueling System - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel exchange device for a fast breeder reactor using liquid metal as a coolant.

[0002]

2. Description of the Related Art A fast breeder reactor uses fast neutrons and has a higher rate of producing new fissile material by absorbing neutrons into nuclear fuel material than by consuming nuclear fuel required for a chain reaction. Since heat is extracted from a small core, sodium, which has a good heat transport capacity, is used as a coolant. Since the sodium must not be exposed to the air, the reactor vessel is sealed and the liquid level is covered with an inert gas. The upper lid of the furnace is strictly sealed and serves as a shield. However, the fuel needs to be changed without opening the lid, so various measures are required.

FIG. 4 is a configuration diagram of a conventional direct-acting refueling apparatus. In FIG. 4, a door valve 5 is provided on the upper surface of the rotary plug 8, the fuel exchange device main body 1 is installed on the door valve 5, the integral gripper 3 is lifted by the wire rope 6, and the wire rope is wound by an electric drum (not shown). The gripper 3 is moved up and down by unwinding. Gripper 3
Is constituted by a cylindrical container enclosing an actuator rod for opening and closing the claw connected at the tip thereof, and is provided with a gripper driving device 4 at an upper portion.

FIG. 5 is an enlarged view of a portion V in FIG. To open and close the gripper claw, the actuator rod 14 for opening and closing the claw at the tip of the gripper is moved up and down, the cam of the gripper claw 12 is moved to open and close, and the gripper driving device is rotated below to rotate the entire gripper cylindrical container. . 7 is the gripper claw 1
2 illustrates a stroke of the actuator rod 14 that opens and closes the actuator rod 2. The seal of this type of direct-acting refueling device is provided with a shaft sealing device 2 in a portion below the refueling device main body 1 through which the gripper 3 passes, and sealed by a special gland packing having a sodium wiping function. I have.

[0005]

The conventional refueling system has the following problems in operating the fast breeder reactor. When the gripper is repeatedly moved up and down, the sodium adhering to the outer surface of the gripper sodium immersion part moves when the gripper repeatedly passes through the gland packing part, causing the gripper lifting load to fall due to the sodium. Increase. For this reason, it is necessary to frequently replace the gland packing in order to prevent the lifting and lowering from stopping due to a large lifting load of the gripper during operation and the phenomenon of lifting and stopping. Since the gripper cannot handle an object having a shape other than the core component pan drigging head, a special handling machine is required to handle the furnace internal structure having the odd-shaped handling head.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a refueling device that prevents a portion of a gripper immersed in sodium in a fast breeder reactor from coming into contact with a gland packing of a shaft sealing device to prevent an increase in gripper lifting load. And Also,
An object of the present invention is to provide a refueling apparatus capable of handling a reactor internal having a handling head other than a core component of a fast breeder reactor.

[0007]

A fuel exchange device main body, a gripper driving device housed in the fuel exchange device main body and raised and lowered by a wire rope, a cylindrical gripper coupled below the gripper driving device, In a fuel exchange device for a fast breeder reactor equipped with a shaft sealing device that seals the gripper, an outer ring fixed in a lower portion of the fuel exchange device main body and having an elevating bearing and packing, and the gripper driving device. The above object is achieved by providing a shaft sealing device which is suspended via a tensioner, is supported on the inner diameter side of the outer ring so as to be able to move up and down, and includes an inner ring having an upper packing and a lower stopper. To achieve.

[0008] Further, the refueling device main body, a gripper driving device housed in the refueling device main body and moved up and down by a wire rope, a cylindrical gripper coupled below the gripper driving device, and a shaft connected to the gripper. A fuel exchange device for a fast breeder reactor equipped with a shaft sealing device for sealing, the adapter having a detachable head on a gripper claw of the gripper, and having an adapter claw engageable with a handling head of a furnace internal structure; The above object is achieved by providing an actuator rod which is built into the gripper and protrudes from the gripper head and opens and closes the adapter claw, and an actuator attached to the middle of the actuator rod and which opens and closes the gripper claw. To achieve.

[0009]

In the present invention, the gripper shaft sealing device has a double structure of an outer ring and an inner ring, and the inner ring moves up and down following the gripper. Since the sodium adhering to the surface does not come into contact, the gripper lifting load due to the sodium adhering does not increase.
Further, since the sodium immersion portion of the gripper is included in the shaft sealing device, diffusion of the activated sodium can be prevented.

Further, in the present invention, when handling an irregular structure having a handling head different from the core component, an adapter having a shape adapted to the handling head of the furnace internal structure is mounted on the gripper, and the adapter is built in the gripper. By operating the actuated rod, the adapter claws can be opened and closed to handle the furnace internals.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a structural view of a refueling apparatus provided with a shaft sealing device according to the present invention. In FIG. 1, the same parts as those in FIG. 4 are denoted by the same reference numerals. 1, the refueling device main body 1, gripper 3, gripper driving device 4, door valve 5, and wire rope 6 are the same as those in FIG. FIG. 2 is a detailed view of the shaft sealing device of FIG. In FIG. 2, the gripper 3 is connected to a gripper driving device 4, and the gripper driving device 4 is suspended by a wire rope 6. The lifting and lowering is performed by winding the wire rope by a winding drum (not shown).
It is performed by unwinding. The gripper driving device 4 rotates the gripper 3 and opens and closes the pawl. A shaft sealing device according to an embodiment of the present invention is fixed in a lower portion of a refueling device main body, and has an outer ring 1 having a lifting bearing 20 and a packing 19.
7 and an inner ring 18 suspended from the gripper driving device 4 via a tensioner 21 and supported on the inner diameter side of the outer ring 17 so as to be able to move up and down, and having an upper packing 19 and a lower stopper 12. The shaft sealing device 2 was provided. The tensioner 21 uses a spring-shaped metal plate. When the gripper 3 is lifted from the lower limit, the inner ring 18 rises while sliding along the seal portion of the outer ring 17 following the gripper. When the gripper 3 is further pulled up, the stopper 12 of the inner ring 8 is caught on the fixing portion, and the tensioner 21
While the gripper 3 only rises and reaches the upper limit.
At this time, the portion of the gripper 3 immersed in sodium is accommodated in the inner ring 18, and the portion immersed in sodium is not raised up to the packing 19 of the inner ring 18. Therefore, the sodium of the gripper 3 does not come into contact with the outer ring 17. When the gripper 3 moves down, the inner ring 17 operates in the opposite direction to the case where the gripper 3 moves up.

Embodiment 2 FIG. 3 is a configuration diagram of an adapter showing an embodiment of a refueling apparatus using the adapter of the present invention. 1, the refueling device main body 1, gripper 3, gripper driving device 4, door valve 5, and wire rope 6 are the same as those in FIG. In FIG. 3, the refueling apparatus according to the embodiment of the present invention has an adapter claw 1 having a detachable head 11a on a gripper claw 12 and capable of engaging with a furnace internal structure.
And an adapter claw 13 which is built in the gripper 3 and protrudes the rod head 14a from the gripper 3.
And an actuator rod 14b attached to the middle of the actuator rod 14 for opening and closing the gripper claw 12. The actuator rod 14 moves in conjunction with both the gripper and the adapter,
In the position shown in FIG. 3, the rod head 14a is at the position A, the actuator 14b is at the position D, the adapter pawl 13 is opened to engage with the handling head of the furnace internal structure, and the gripper pawl 12 is Is engaged. When the actuator rod 14 is raised by the adapter claw opening / closing stroke 15, the rod head 14a is at the position B and the actuator 14b is at the position E. At this time, the adapter claw 13 is closed and the engagement of the furnace internal structure with the handling head is released, and the gripper claw 12 is engaged with the adapter 11 while being opened. When the actuator rod 14 is further raised by the gripper claw opening / closing stroke 16, the rod head 14a
Is at the position C, and the actuator 14b is at the position F. At this time, the adapter claw 13 is kept closed, the gripper claw 12 is closed, and the engagement of the adapter 11 with the head 11a is released. By exchanging the adapter 11, various internal structures can be handled.

[0013]

According to the present invention, the shaft seal device of the gripper has a double structure, the gripper is housed in the inner ring, and the inner ring follows the gripper and contacts the seal portion of the outer ring. Since the gripper sodium does not come into contact with the outer annular seal portion, the gripper lifting load does not increase due to sodium attached to the gripper. Therefore, since the gland packing is not damaged, it is not necessary to frequently replace the gland packing. Further, since the sodium immersion portion of the gripper is included in the shaft sealing device, public exposure due to diffusion of activated sodium can be reduced.

Since the adapter for engaging the handling head of the in-furnace structure is attached to the tip of the gripper, the handling of the in-furnace structure having the odd-shaped handling head does not require the use of a dedicated handling machine. In addition, since the replacement operation inside the furnace can be performed with one refueling device, the work of attaching and detaching the dedicated handling machine is not required, and the operation time can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a fuel exchange device according to a first embodiment of the present invention.

FIG. 2 is a detailed view of the shaft sealing device of FIG. 1;

FIG. 3 is a configuration diagram of an adapter of a refueling apparatus according to Embodiment 2 of the present invention.

FIG. 4 is a configuration diagram of a conventional fuel exchange device for a fast breeder reactor.

FIG. 5 is an enlarged view of a portion V in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Refueling device main body 2 Shaft sealing device 3 Gripper 4 Gripper drive device 11 Adapter 12 Gripper claw 13 Adapter claw 14 Actuator rod 14a Rod head 14b Actuator 15 Adapter opening / closing stroke 16 Gripper claw opening / closing stroke 17 Outer ring 18 Inner ring 19 Packing 20 Lifting bearing 21 Tensioner 22 Stopper

Claims (2)

(57) [Claims] 1. A refueling device main body, a gripper driving device housed in the refueling device main body and raised and lowered by a wire rope, a cylindrical gripper coupled below the gripper driving device, and a shaft mounted on the gripper. In a fast breeder reactor fuel exchange device including a shaft sealing device for sealing, an outer ring having a lifting bearing and a packing fixed inside a lower portion of the fuel exchange device main body, and a gripper driving device via a tensioner A fuel for a fast breeder reactor, comprising: a shaft sealing device that is suspended and supported on the inner diameter side of the outer ring so as to be able to move up and down, and includes an inner ring having an upper packing and a lower stopper. Exchange equipment. 2. A refueling device main body, a gripper driving device housed in the refueling device main body and moved up and down by a wire rope, a cylindrical gripper coupled below the gripper driving device, and a shaft mounted on the gripper. A fuel exchange device for a fast breeder reactor equipped with a shaft sealing device for sealing, the adapter having a detachable head on a gripper claw of the gripper, and having an adapter claw engageable with a handling head of a furnace internal structure; An actuator rod that is built into the gripper and protrudes from the gripper head to open and close the adapter claw; and an actuator rod that is attached in the middle of the actuator rod,
A fuel exchange device for a fast breeder reactor, comprising: an actuator for opening and closing the gripper claw.