JP2013238464A - Inert gas boundary forming facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inert gas boundary forming facility that has a simple shape of an entire device, is easily connected to a shielding plug, and can limit a range of an inert gas boundary to a required minimum range.SOLUTION: An inert gas boundary forming facility includes: a collar 13 that is made of metal, is formed into an annular shape, is disposed at a peripheral portion 3a-1 of a taking-out hole 31 on a top surface 3a of a shielding plug 3, and surrounds the taking-out hole; guide piping 11 that is made of metal, is formed into a cylindrical shape, and is disposed above the taking-out hole; and a flexible bag 12 that is made of a flexible material, is formed into a cylindrical shape, is provided with glove ports 34 attached with gloves 33, and has an upper end portion 12a connected to a lower end portion 11b of the guide piping and a lower end portion 12b connected to the collar. Further, the flexible bag is provided with an upper side telescopic portion 12d and a lower side telescopic portion 12e. The upper side telescopic portion is disposed on an outer peripheral surface 11c of the lower end portion of the guide piping, and the lower side telescopic portion has only one gathering 12e-1 protruding outside the flexible bag.

Description

  The present invention relates to an inert gas boundary forming facility for forming an inert gas boundary on a shielding plug that closes an upper part of a reactor vessel when performing a replacement operation of an internal structure of a fast breeder reactor.

  The fast breeder reactor has a core part loaded with a plurality of fuel assemblies using a mixed oxide of uranium and plutonium as fuel in the reactor vessel, while the plutonium is fissioned with fast neutrons, Since uranium can absorb fast neutrons and produce a larger amount of plutonium than the plutonium that undergoes fission, it is highly expected as a future energy source.

  In such a fast breeder reactor, liquid metal sodium is used as a coolant for the core, and a liquid level of the liquid metal sodium in the reactor vessel and a shielding plug closing the upper portion of the reactor vessel. The space between them is filled with an inert gas (argon gas). As the shielding plug, there is known a double rotating plug type having a large rotating plug and a small rotating plug incorporated eccentrically. Further, in the reactor vessel, in addition to the core portion, an in-core structure such as a core upper mechanism disposed above the core portion is also provided.

Japanese Patent Laid-Open No. 11-109071

  Currently, in the existing fast breeder reactor, replacement work of the upper core mechanism is planned. In this replacement operation, it is necessary to put the core upper mechanism in and out of the carry-out hole (through hole) formed in the shielding plug (small rotating plug). At this time, the inert gas filled in the reactor vessel is It flows out from the carry-out hole. For this reason, it is necessary to prevent the worker from sucking the inert gas to be in an oxygen deficient state or releasing the inert gas that may contain radioactive dust as it is into the atmosphere.

Therefore, in the replacement operation of the core upper mechanism, it is necessary to provide an inert gas boundary forming facility for forming an inert gas boundary on the shielding plug.
In this case, since many facilities are installed on the shielding plug, when an inert gas boundary having a shape corresponding to these facilities is formed, the inert gas boundary forming facility has a complicated shape. End up. For this reason, it was initially planned to form the inert gas boundary using a simple-shaped inert gas boundary forming facility that covers the entire shielding plug (small rotating plug).

  However, in such an inert gas boundary forming facility, since the range of the inert gas boundary is widened, there is a possibility that the worker may have trouble accessing the target facility on the shielding plug. For example, there is a possibility that a worker may be injured when walking on the inert gas boundary forming facility in order to access the target facility, or that the inert gas boundary forming facility may be damaged.

  Therefore, in view of the above circumstances, the present invention has an inert gas which has a simple shape as a whole and can be easily engaged with a shielding plug, and can limit the range of the inert gas boundary to the minimum necessary. It is an object to provide a boundary forming facility.

The inert gas boundary forming facility according to the first aspect of the present invention for solving the above-mentioned problems is the fast breeder reactor in which the discharge hole for the reactor internal structure is formed in the shielding plug closing the upper part of the reactor vessel. An inert gas boundary forming facility for forming an inert gas boundary on the shielding plug in order to perform an object replacement operation,
A collar made of metal and formed in an annular shape, disposed on the periphery of the carry-out hole on the upper surface of the shielding plug and surrounding the carry-out hole;
A guide tube made of metal and formed in a cylindrical shape and disposed above the carry-out hole;
A flexible material made of a flexible material, formed in a cylindrical shape and provided with a working portion for an operator, with an upper end connected to the lower end of the guide tube and a lower end connected to the collar Sex back and
It is characterized by having.

Further, the inert gas boundary forming equipment of the second invention is the inert gas boundary forming equipment of the first invention,
The working unit is a glove port to which a glove is attached.

Further, the inert gas boundary forming equipment of the third invention is the inert gas boundary forming equipment of the first or second invention,
The flexible bag has a bellows-like upper elastic part provided at the upper end part and capable of extending in the vertical direction, and a bellows-like lower elastic part provided at the lower part and capable of extending in the vertical direction. It is characterized by.

Moreover, the inert gas boundary formation equipment of 4th invention is the inert gas boundary formation equipment of 3rd invention,
The upper elastic part of the flexible bag is arranged on the outer peripheral surface of the lower end part of the guide tube.

Further, the inert gas boundary forming equipment of the fifth invention is the inert gas boundary forming equipment of the third or fourth invention.
The lower elastic part of the flexible bag has only one ridge protruding to the outside of the flexible bag.

Moreover, the inert gas boundary formation equipment of 6th invention is the inert gas boundary formation equipment of any one of 1st-5th invention,
The collar has an annular body part on the upper side, an annular part on the lower side, and an obstacle avoiding part that bulges outward to avoid an obstacle present at the peripheral part of the carry-out hole in a part of the circumferential direction. It is the adapter part which has.

According to the inert gas boundary forming facility of the first aspect of the present invention, in the fast breeder reactor in which the discharge hole for the internal structure of the reactor is formed in the shielding plug covering the upper part of the reactor vessel, the replacement of the internal structure of the reactor is performed. An inert gas boundary forming facility for forming an inert gas boundary on the shielding plug for performing work, which is made of metal and formed in an annular shape, and a peripheral portion of the carry-out hole on the upper surface of the shielding plug And a collar that surrounds the periphery of the carry-out hole, a metal-made cylindrical shape, a guide tube that is disposed above the carry-out hole, and a flexible material that is cylindrical And a working portion for an operator is provided, and has a flexible back having an upper end connected to the lower end of the guide tube and a lower end connected to the collar. Because the shape on the shielding plug The scope of the inert gas boundary to be, can be limited to a minimum extent necessary to withdraw the furnace structure, the shape of the entire apparatus is also simple. For this reason, it becomes easy for an operator to access the target equipment on the shielding plug, and there is no possibility that the worker walks on the inert gas boundary forming equipment and is injured or damages the inert gas boundary forming equipment.
Further, the use of the collar facilitates the engagement with the shielding plug, and facilitates the attachment of the flexible bag and the guide tube.
In addition, since the working part for the worker is provided in the flexible bag, the flexible bag is bent when the worker works in the working part, so that the work can be easily performed.

  According to the inert gas boundary forming facility of the second aspect of the invention, in the inert gas boundary forming facility of the first aspect of the invention, the working part is a glove port to which a glove is attached. When the hand is put into the glove from the glove port and the O-ring is removed, for example, the flexible bag is bent, so that the O-ring can be easily removed.

  According to the inert gas boundary forming equipment of the third aspect of the invention, in the inert gas boundary forming equipment of the first or second aspect, the flexible bag is accordion-like provided at the upper end and can be expanded and contracted in the vertical direction. It is characterized by having an upper upper stretchable part and a bellows-like lower stretchable part provided at the lower end part, which can be expanded and contracted in the vertical direction, so that a worker in a working part (such as a glove port attached with a glove) However, when the work is performed, the upper elastic part and the lower elastic part can be expanded and contracted in the vertical direction so that the position of the working part can be moved in the vertical direction.

  According to the inert gas boundary forming facility of the fourth aspect of the invention, in the inert gas boundary forming facility of the third aspect of the invention, the upper stretchable portion of the flexible bag is disposed on the outer peripheral surface of the lower end portion of the guide tube. Since the upper telescopic part can be expanded and contracted in the vertical direction, the horizontal displacement is prevented by the lower end part of the guide tube. For this reason, when pulling up the in-furnace structure, it is possible to prevent the upper elastic part of the flexible bag from being displaced inward in the horizontal direction and interfering with the in-furnace structure.

  According to the inert gas boundary forming equipment of the fifth invention, in the inert gas boundary forming equipment of the third or fourth invention, the lower elastic part of the flexible bag protrudes outside the flexible bag. Since it has only one ridge, the lower expansion / contraction part can be easily expanded and contracted in the vertical direction, but is not easily displaced in the horizontal direction. For this reason, when pulling up the in-furnace structure, it is possible to prevent the lower elastic part of the flexible bag from being displaced inward in the horizontal direction and interfering with the in-furnace structure.

  According to the inert gas boundary forming facility of the sixth aspect of the present invention, in the inert gas boundary forming facility of any one of the first to fifth aspects of the invention, the collar is an annular main body on the upper side and a circular on the lower side. The peripheral portion of the carry-out hole is characterized by being an adapter portion having an obstruction avoiding portion that swells outward while avoiding the obstacle present at the peripheral portion of the carry-out hole in a part of the ring and in the circumferential direction. Even if there is an obstacle, the flexible bag and the guide tube can be attached easily and reliably by using the collar provided with the adapter part having the obstacle avoiding part.

It is a schematic diagram which shows the state which installed the inert gas boundary formation equipment which concerns on the embodiment of this invention on the shielding plug of the reactor vessel of a fast breeder reactor. It is AA arrow sectional drawing of FIG. It is the B section expanded sectional view of FIG. It is a perspective view which decomposes | disassembles and shows the inert gas boundary formation equipment which concerns on the embodiment of this invention. It is the C section expanded sectional view of FIG. It is a longitudinal cross-sectional view (FF sectional view taken on the line of FF of FIG. 7) which shows the other structural example of the color which comprises the inert gas boundary formation installation which concerns on the embodiment of this invention. FIG. 7 is a view taken in the direction of arrow E in FIG. 6. FIG. 7 is a cross-sectional view taken along line GG in FIG. 6.

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

  First, based on FIG.1 and FIG.2, the outline | summary of the reactor container vicinity of a fast breeder reactor and the inert gas boundary formation equipment which concerns on the example of embodiment of this invention is demonstrated.

In the reactor vessel 4 of the fast breeder reactor, a reactor core 5 and core structures such as a core upper mechanism 2 disposed above the core 5 (other core structures are not shown) Is provided). The reactor vessel 4 is filled with an inert gas (argon gas).
The core 5 is loaded with a plurality of fuel assemblies using a mixed oxide of uranium and plutonium as fuel. The shielding plug 3 is of a double rotary plug type having a large rotary plug 3A and a small rotary plug 3B eccentrically incorporated therein. The shielding plug 3 closes the upper part of the reactor vessel 4 and is not placed in the reactor vessel 4. An active gas boundary is formed.

  By rotating the large rotary plug 3A and the small rotary plug 3B by a plug driving device (not shown), positioning of the core upper mechanism 2 and positioning of the fuel exchanger (not shown) can be performed. FIG. 1 shows a state where the core upper mechanism 2 is shifted from the core 5 by the rotation of the large rotary plug 3A and the small rotary plug 3B.

  The reactor vessel 4 has an upper end 4 a supported by the floor surface 7 of the reactor upper pit 6, and is inserted into the through hole 7 a of the floor surface 7 and extends downward. A temporary furnace upper pit lid 8 is provided on the upper part of the furnace upper pit 6 for performing an exchange operation of the core upper mechanism 2 or the like.

  In order to replace the core upper mechanism 2, an inert gas boundary forming facility 1 for temporarily forming an inert gas boundary 1 a is temporarily installed on the shielding plug 3.

  Next, based on FIGS. 1-5, the structure of the inert gas boundary formation installation 1 etc. are explained in full detail.

  The core upper mechanism 2 is provided with a control rod guide tube, an instrument tube, etc. (not shown) in a cylindrical body 2a, and has a circular shape formed on the shielding plug 3 (small rotating plug 3B) ( That is, it is inserted through the carry-out hole 31 having a circular shape in top view and extends downward. A flange portion 2 b is provided at the upper end of the trunk portion 2 a of the core upper mechanism 2, and this flange portion 2 a is supported by a step portion 31 a formed in the carry-out hole 31. A double O-ring 41 is interposed between the flange portion 2a and the stepped portion 31a. Normally, a gap between the reactor core upper mechanism 2 (body portion 2a) and the carry-out hole 31 is not connected to the inside of the reactor vessel 4. The active gas is prevented from leaking by the double O-ring 41.

  However, during the replacement work, if the core upper mechanism 2 is lifted by a lifting means (not shown) such as a crane or a jack as shown by a one-dot chain line in FIG. The active gas flows out from the carry-out hole 31. At this time, the shielding plug 3 is used to prevent the worker from sucking the inert gas into an oxygen deficient state or releasing the inert gas that may contain radioactive dust as it is into the atmosphere. The inert gas boundary forming equipment 1 is installed on the (small rotating plug 3B).

  The inert gas boundary forming facility 1 includes a guide tube 11, a flexible back 12 (generally also referred to as a plastic back), and a collar 13, and the inside thereof becomes an inert gas boundary 1a. The outside of the inert gas boundary forming equipment 11 is an air atmosphere. 3 and the like show a state in which radioactive dust 42 is contained in the inert gas that flows out from the reactor vessel 4 and flows into the inert gas boundary forming facility 1 (inert gas boundary 1a). Illustrated.

  The collar 13 is made of metal (made of SUS in the illustrated example) and formed in an annular shape, and is disposed on the peripheral edge 3a-1 of the carry-out hole 31 on the upper surface 3a of the shielding plug 3 (small rotating plug 3B). 31 is surrounded. Since the collar 13 is fixed to the peripheral edge 3a-1 of the carry-out hole 31 by spot welding and the space between the spot welds is closed by caulking, the collar 13 is in close contact with the peripheral edge 3a-1 of the carry-out hole 31. Has been. In addition, it is not limited to such a fixing method, The collar 13 should just be closely_contact | adhered to the peripheral part 3a-1 of the carry-out hole 31. FIG.

  The guide tube 11 is made of metal (SUS in the illustrated example) and is formed in a cylindrical shape, and is disposed above the carry-out hole 31. More specifically, the guide tube 11 is inserted through a through hole 32 formed in the furnace upper pit lid 8 and extends downward, and a flange portion 11 a formed at the upper end is formed on the upper surface 8 a of the furnace upper pit lid 8. The peripheral portion 8a-1 of the through hole 32 is supported. Further, the upper end of the guide tube 11 is closed by a lid member 14. As the lid member 14, for example, a pedestal member or a door valve mounted with a lifting means can be used. The upper core mechanism 2 can be lifted by a lifting means mounted on the lid member 14 or a lifting means installed above the guide tube 11.

  The flexible back 12 is made of a flexible material (made of vinyl in the illustrated example) and is formed in a cylindrical shape. The flexible bag 12 is provided with a glove port 34 to which a glove 33 is attached as a working part for an operator. The globe port 34 is made of metal (made of SUS in the illustrated example), and has a hole 34a for an operator to insert a hand. The globe 33 is formed of a stretchable material such as rubber or vinyl, and a base end portion is attached to a peripheral portion of the hole 34a in the globe port 34 (for example, fixed by an adhesive or an adhesive tape). .

  Therefore, the worker can insert his / her hand into the globe 33 through the hole 34 a of the globe port 34. In FIG. 3, the state where the globe 33 is in the flexible bag 12 is indicated by a solid line. However, when the core upper mechanism 2 is pulled out, the globe 33 interferes with the core upper mechanism 2. In order to prevent this, the glove 33 is pulled out of the flexible bag 12 from the hole 34a of the glove port 34 as shown by a one-dot chain line in FIG.

  The upper end 12 a of the flexible back 12 is connected to the lower end 11 b of the guide tube 11, and the lower end 12 b of the flexible back 12 is connected to the collar 13.

  More specifically, the lower end 12b of the flexible back 12 is fitted to the outer peripheral surface 13a of the collar 13, and is tightened by the band 43 from the outer peripheral surface 12c side of the lower end 12b of the flexible back 12. The lower end portion 12b of the back 12 is brought into close contact with the collar 13 to prevent the inert gas from leaking. Further, by winding an adhesive tape 44 made of aluminum or the like around the lower end 12b and the collar 13 of the flexible back 12 from the outside, leakage of the inert gas can be prevented more reliably.

  Similarly, the upper end portion 12a of the flexible back 12 is fitted to the outer peripheral surface 11c of the lower end portion 11b of the guide tube 11, and is tightened by the band 45 from the outer peripheral surface 12c side of the upper end portion 12a of the flexible back 12. The upper end 12a of the flexible bag 12 is brought into close contact with the lower end 11b of the guide tube 11 to prevent the inert gas from leaking. Further, by winding an adhesive tape 46 made of aluminum or the like around the upper end portion 12a of the flexible back 12 and the lower end portion 11b of the guide tube 11, leakage of the inert gas can be prevented more reliably. Yes.

  In addition, the flexible bag 12 has a bellows shape provided at the upper end portion 12a and can be vertically expanded as indicated by an arrow D1, and a bellows shape provided at the lower end portion 12b. A lower expansion / contraction portion 12e that can expand and contract in the direction.

  The upper expansion / contraction part 12d of the flexible bag 12 has a bellows shape having a plurality (five in the illustrated example) of flanges 12d-1, and is disposed on the outer peripheral surface 11c of the lower end part 11b of the guide tube 11. Yes. For this reason, the upper telescopic part 12d can be expanded and contracted in the vertical direction, while the horizontal displacement is prevented by the lower end part 11b of the guide tube 11.

  The lower elastic part 12e of the flexible bag 12 has only one ridge 12e-1 protruding to the outside of the flexible bag 12. For this reason, the lower expansion / contraction part 12e has a structure that can be easily expanded and contracted in the vertical direction but is not easily displaced in the horizontal direction.

  In FIG. 3, the state before the upper elastic part 12 d and the lower elastic part 12 e of the flexible bag 12 expands and contracts is shown by a one-dot chain line. In this state, the operator puts the existing elastic hand in the glove 33. For example, when a downward force is applied to the glove port 34 by the worker by removing the O-ring 41 or the like, as shown by a solid line in FIG. By contracting downward, the globe port 34 moves downward.

  Next, another configuration example of the collar 13 will be described with reference to FIGS. The collar 13 shown in FIGS. 6 to 8 is made of metal (made of SUS in the illustrated example) having an upper body portion 13A and a lower adapter portion 13B. The main body portion 13A and the adapter portion 13B of the collar 13 may be integrally molded, or may be joined by a joining means such as welding.

  In the case of such a collar 13, the lower end portion 12 b of the flexible bag 12 is connected to the main body portion 13 </ b> A of the collar 13. As a specific example of the connection structure, the same structure as that of the collar 13 described above can be used. That is, by fitting the lower end 12b of the flexible back 12 to the outer peripheral surface 13A-1 of the main body 13A of the collar 13 and tightening it with the band 43 from the outer peripheral surface 12c side of the lower end 12b of the flexible back 12. The lower end 12b of the flexible bag 12 is brought into close contact with the main body 13A of the collar 13 to prevent the inert gas from leaking. Further, the adhesive tape 44 is wound around the lower end 12b of the flexible bag 12 and the main body 13A of the collar 13 from the outside, thereby preventing leakage of the inert gas more reliably.

  The adapter portion 13B has an annular shape, and an obstacle avoiding portion 13B-1 projects from a part of the circumferential direction of the adapter portion 13B. The obstacle avoiding portion 13B bulges outside the obstacle (for example, flange) 47 present at the peripheral edge portion 3a-1 of the carry-out hole 31 on the upper surface 3a of the shielding plug 3 (small rotating plug 3B).

  Therefore, in this collar 13, the main body portion 13A and the adapter portion 13B are disposed at the peripheral edge portion 3a-1 of the carry-out hole 31 so as to surround the carry-out hole 31, and the obstacle avoidance portion 13B-1 of the adapter portion 13B. However, the obstacle 47 is avoided by surrounding the obstacle 47.

  In this case, the adapter portion 13B of the collar 13 is fixed to the peripheral edge portion 3a-1 of the carry-out hole 31, for example, by spot welding, and the gap between the spot welds is closed with caulking to thereby make the peripheral edge portion 3a of the carry-out hole 31. -1. In addition, it is not limited to such a fixing method, The adapter part 13B of the collar 13 should just be closely_contact | adhered to the peripheral part 3a-1 of the carry-out hole 31. FIG.

  In addition, although the example of illustration shows the case where there is one obstacle 47, the collar 13 having the adapter portion 13B is applied even when there are a plurality of obstacles in the peripheral edge 3a-1 of the carry-out hole 31. can do. In this case, the obstacle avoiding unit 13B-1 of the adapter unit 13B may be a single part that surrounds all of the plurality of obstacles (when a plurality of obstacles are close to each other), and individually surrounds the obstacles. It may be a plurality of parts (when a plurality of obstacles are separated).

As described above, according to the inert gas boundary forming facility 1 of the present embodiment, the carry-out hole 31 of the core upper mechanism 2 is connected to the shielding plug 3 (small rotating plug 3B) blocking the upper part of the reactor vessel 4. Is an inert gas boundary forming facility for forming the inert gas boundary 1a on the shielding plug 3 (small rotating plug 3B) in order to replace the core upper mechanism 2 in the fast breeder reactor in which is formed. A collar 13 that is made of metal and formed in an annular shape and is disposed at the peripheral edge 3a-1 of the carry-out hole 31 on the upper surface 3a of the shielding plug 3 (small rotation plug 3B) and surrounds the circumference of the carry-out hole 31; A guide tube 11 made of metal and formed in a cylindrical shape and disposed above the carry-out hole 31; and a globe 33 made of a flexible material and formed in a cylindrical shape and serving as a working portion for an operator. Attached group The shield port is provided with a flexible port 12 having an upper end 12 a connected to the lower end 11 b of the guide tube 11 and a lower end 12 b connected to the collar 13. The range of the inert gas boundary formed on the 3 (small rotating plug 3B) can be limited to the minimum range necessary for pulling out the core upper mechanism 2, and the overall shape of the apparatus is also simple. For this reason, it becomes easy for an operator to access the target equipment on the shielding plug 3, and there is a risk that the worker walks on the inert gas boundary forming equipment 1 to be injured or damage the inert gas boundary forming equipment 1. Nor.
Further, the use of the collar 13 facilitates the engagement with the shielding plug 3 and facilitates the attachment of the flexible bag 12 and the guide tube 11.
Further, since the glove port 34 to which the glove 33 is attached is provided on the flexible bag 12 as a work part for the worker, the worker puts his hand into the glove 33 from the glove port 34 and removes the O-ring 41, for example. Since the flexible back 12 bends when performing, the removal operation of the O-ring 41 can be easily performed.

  In addition, according to the inert gas boundary forming facility 1 of the present embodiment, the flexible bag 12 is formed of an upper bellows-like upper telescopic part 12d provided on the upper end part 12a and the lower end part. 12b, and has a lower expansion / contraction portion 12e that can be expanded and contracted in the vertical direction. Therefore, when an operator works in the glove port 34 to which the glove 33 is attached, the upper expansion / contraction is performed. Since the part 12d and the lower expansion / contraction part 12e can expand and contract in the vertical direction and the position of the glove port 34 can be moved in the vertical direction, the operation can be performed more easily.

  Further, according to the inert gas boundary forming facility 1 of the present embodiment, the upper stretchable portion 12d of the flexible back 12 is disposed on the outer peripheral surface 11c of the lower end portion 11b of the guide tube 11. Because of the feature, the upper extension / contraction part 12d can be extended / contracted in the vertical direction, while the horizontal displacement is prevented by the lower end part 11b of the guide tube 11. For this reason, when pulling up the core upper mechanism 2, it is possible to prevent the upper elastic part 12d of the flexible back 12 from being displaced inward in the horizontal direction and interfering with the core upper mechanism 2.

  In addition, according to the inert gas boundary forming facility 1 of the present embodiment, the lower elastic part 12e of the flexible bag 12 has only one ridge 12e-1 protruding outside the flexible bag 12. Since it is characterized by having, it has the structure where the lower expansion-contraction part 12e can be expanded-contracted easily to an up-down direction, but is hard to displace to a horizontal direction. For this reason, when pulling up the core upper mechanism 2, it is possible to prevent the lower expansion / contraction part 12e of the flexible back 12 from being displaced inward in the horizontal direction and interfering with the core upper mechanism 2.

  In addition, according to the inert gas boundary forming facility 1 of the present embodiment, the collar 13 is an annular main body 13A on the upper side, the lower side is annular, and the carry-out hole 31 is partly in the circumferential direction. Since the adapter portion 13B has an obstacle avoiding portion 13B-1 that swells outward while avoiding the obstacle 47 existing in the peripheral portion 3a-1, the peripheral portion 3a-1 of the carry-out hole 31 Even if the obstacle 47 exists, the flexible bag 12 and the guide tube 11 can be easily and reliably attached by using the collar 13 provided with the adapter part 13b having the obstacle avoiding part 13B-1. it can.

In the above description, the case where the core upper mechanism 2 is replaced has been described. However, the present invention is not limited to this, and the inert gas boundary forming facility of the present invention is also used when replacing other in-furnace structures. Can be applied.
In addition, the inert gas boundary forming equipment of the present invention is useful when applied to the case where the working part for the worker is the glove port 34 to which the glove 33 is attached, but is always limited to this. However, the present invention can be applied to a case where a working unit other than the glove port is provided. Examples of the working unit other than the globe port include a fiberscope for observing the inside of an inert gas boundary.

  The present invention relates to an inert gas boundary forming facility for forming an inert gas boundary on a shielding plug covering the upper part of a reactor vessel of a fast breeder reactor, and relates to the shape of the entire apparatus and the connection with the shielding plug. The present invention is useful when the shape is simplified and the range of the inert gas boundary is limited to a necessary minimum.

DESCRIPTION OF SYMBOLS 1 Inert gas boundary formation equipment 1a Inert gas boundary 2 Core upper part mechanism 2a Core part of core upper part mechanism 2b Flange part of trunk part 3 Shielding plug 3A Large rotation plug 3B Small rotation plug 3a Upper surface of shielding plug (small rotation plug) 3a -1 Perimeter of unloading hole 4 Reactor vessel 4a Upper end of reactor vessel 5 Reactor core 6 Reactor upper pit 7 Reactor upper pit floor 8 Reactor upper pit lid 8a Reactor upper pit lid upper surface 8a-1 Peripheral portion 11 Guide tube 11a Guide tube flange 11b Guide tube lower end 11c Guide tube (lower end) outer peripheral surface 12 Flexible back 12a Flexible back upper end 12b Flexible back lower end 12c Possible Outer peripheral surface of flexible back (upper end, lower end) 12d Upper elastic part of flexible bag 12d-1 Upper elastic part 12e Lower elastic part of flexible bag 12e-1 Collar of lower expansion / contraction part 13 Color 13a Color outer peripheral surface 13A Color main body part 13A-1 Main body outer peripheral surface 13B-1 Obstacle avoiding part 14 Lid member 31 Unloading hole for shielding plug (small rotation plug) 31a Step portion of the carry-out hole 32 Through-hole in the furnace upper pit lid 33 Globe 34 Globe port 34a Globe port hole 41 O-ring 42 Radioactive dust 43 Band 44 Adhesive tape 45 Band 46 Adhesive tape 47 Obstacle

Claims (6)

In a fast breeder reactor in which a discharge hole for a reactor internal structure is formed in a shield plug that closes the upper part of the reactor vessel, an inert gas boundary is placed on the shield plug in order to replace the reactor internal structure. An inert gas boundary forming facility for forming
A collar made of metal and formed in an annular shape, disposed on the periphery of the carry-out hole on the upper surface of the shielding plug and surrounding the carry-out hole;
A guide tube made of metal and formed in a cylindrical shape and disposed above the carry-out hole;
A flexible material made of a flexible material, formed in a cylindrical shape and provided with a working portion for an operator, with an upper end connected to the lower end of the guide tube and a lower end connected to the collar Sex back and
An inert gas boundary forming facility characterized by comprising: In the inert gas boundary formation equipment according to claim 1,
The inert gas boundary forming facility, wherein the working unit is a glove port to which a glove is attached. In the inert gas boundary forming facility according to claim 1 or 2,
The flexible bag has a bellows-like upper elastic part provided at the upper end part and capable of extending in the vertical direction, and a bellows-like lower elastic part provided at the lower part and capable of extending in the vertical direction. Inert gas boundary forming equipment characterized by. In the inert gas boundary formation equipment according to claim 3,
The inert gas boundary forming facility, wherein the upper expansion / contraction part of the flexible bag is disposed on the outer peripheral surface of the lower end part of the guide tube. In the inert gas boundary formation facility according to claim 3 or 4,
The inert gas boundary forming equipment, wherein the lower elastic part of the flexible bag has only one ridge protruding to the outside of the flexible bag. In the inert gas boundary formation equipment according to any one of claims 1 to 5,
The collar has an annular body part on the upper side, an annular part on the lower side, and an obstacle avoiding part that bulges outward to avoid an obstacle present at the peripheral part of the carry-out hole in a part of the circumferential direction. An inert gas boundary forming facility, characterized by being an adapter part.

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