JP5606275B2 - Working platform unit and method of using the working platform unit - Google Patents

Description

  The present invention relates to a vessel body of a reactor pressure vessel having a side peripheral wall surrounding the periphery of a core structure and a bottom portion provided at a lower portion of the side peripheral wall, and an upper opening of the side peripheral wall being closed by an upper lid. The present invention relates to a work platform unit suitable for use.

  Conventionally, in a maintenance operation or the like inside a nozzle nozzle formed to protrude outward from the side wall of the vessel body, the inside of the reactor pressure vessel is normally filled with a coolant (primary cooling water). Therefore, it was necessary to carry out in an underwater environment. However, when working in an underwater environment, it is necessary to make all the devices waterproof design, and the waterproof specification increases the volume and mass of the device and makes it difficult to handle. Therefore, in recent years, a method for performing maintenance work and the like inside the nozzle nozzle in an air environment has been proposed.

  In the following Patent Document 1, the coolant is drained so that the water level is lower than the nozzle, and a bottomed cylindrical work platform is inserted into the internal space of the trunk. Then, in a state where the opening formed in the side wall of the work base is opposed to the nozzle tube base, a cylindrical shield is inserted into the opening and the nozzle pipe base, and is bolted to the work base. In this way, by shielding the inside of the nozzle pedestal from the internal space of the container body by the shielding body, foreign matters (for example, blasting material and cutting powder) generated by maintenance work fall into the internal space of the container body. It is preventing.

JP 2007-3442 A

  However, in the following Patent Document 1, since the cylindrical shield is bolted after being inserted into the nozzle tube base and the opening of the gantry, it takes time to install. Therefore, in place of such a shield, an expansion / contraction cylinder that can be expanded and contracted toward the opening end of the nozzle tube base is provided around the opening of the side wall of the work platform, and the distal end in the cylinder axis direction of the expansion / contraction cylinder is provided. It is conceivable to use a shielding device in which an elastic ring body is arranged. That is, with the opening of the side wall of the work platform facing the opening end of the nozzle tube base, the telescopic cylinder is extended toward the opening end of the nozzle tube table, and the elastic ring body is extended to the opening end of the nozzle tube table. By pressing and adhering to the periphery, the inside of the nozzle nozzle can be shielded from the inside of the container body more easily than the above-described shielding body.

  By the way, when performing cleaning work and ultrasonic inspection work among the maintenance work inside the nozzle nozzle, the cleaning liquid and coplant are sprayed inside the nozzle nozzle and collected on the gantry side. Along with the flow of liquid, foreign matter flows to the gantry side. In this case, foreign matter enters the concave gap formed between the elastic ring body and the periphery of the nozzle nozzle in a wide range in the circumferential direction, and the periphery of the elastic ring body and the opening end of the nozzle nozzle There is a problem that foreign matter may fall into the container body when the close contact with the container is released.

  The present invention has been made in consideration of such circumstances, and when a liquid is sprayed inside the nozzle nozzle in the operation on the container body of the nuclear pressure vessel, the foreign matter falls into the container body. The challenge is to prevent it.

In order to achieve the above object, the present invention employs the following means.
That is, the work gantry unit according to the present invention includes a side peripheral wall surrounding the periphery of the core structure and a bottom portion provided at a lower portion of the side peripheral wall, and an upper opening of the side peripheral wall is closed by an upper lid. A work gantry unit used for work on a container body of a pressure vessel and capable of working inside a nozzle tube base formed to protrude outward from the side peripheral wall of the container body, from above the container body A cylinder extending toward the upper opening of the container body, a partition wall provided in a lower part of the cylinder body, facing the inner wall surface of the side wall in the internal space of the container body, and a lower part of the partition wall A work chamber partitioned from the inner space of the container body is defined by the wall bottom provided, and the partition is accessed to face the opening end of the nozzle tube base formed on the inner wall surface of the side peripheral wall. A stand with windows A telescopic telescopic cylinder provided in the access window and extending toward the opening end of the nozzle tube base; and provided at a tip in the cylinder axial direction of the telescopic cylinder body, around the opening end of the nozzle base An elastic ring body that is pressed against and in close contact with, and a shielding device that shields the interior of the nozzle pedestal from the internal space of the container body, wherein the elastic ring body extends in a circumferential direction. And a pocket formed on the lower side of the inner peripheral edge to guide the liquid sprayed on the nozzle nozzle side and flowing toward the gantry side to the lower side of the inner peripheral edge.
According to this configuration, the pocket formed on the lower side of the inner peripheral edge guides the liquid downward, so that the foreign matter accompanying the liquid easily flows downward. This makes it easier for foreign matter that enters the concave gap between the elastic ring body and the periphery of the opening end of the nozzle pedestal to gather downward.
Therefore, by using an external suction device or the like, collected foreign substances can be removed together, so that the foreign substances can be easily removed. Therefore, it can prevent that a foreign material falls into the inside of a container trunk.

In addition, the gas can be supplied to the gas discharge section through the gas supply section provided in the pocket and capable of discharging gas, a gas supply flow path communicating with the gas discharge section, and the gas supply flow path. And a gas supply stirring device capable of stirring the liquid accumulated in the pocket by the gas discharged from the gas discharge portion.
According to this configuration, since the gas is discharged and agitated with respect to the liquid accumulated in the pocket, it is possible to suppress the precipitation of foreign substances collected below the inner peripheral edge. In this state, by using an external suction device or the like, it is possible to remove the collected foreign substances while floating, so that the foreign substances can be easily removed.

A liquid discharge passage capable of discharging the liquid accumulated in the pocket from the pocket; a liquid storage portion capable of storing the liquid flowing through the liquid discharge passage; and the pocket. A liquid dischargeable portion, a liquid supply channel communicating with the liquid discharger and the liquid storage unit, and the liquid stored in the liquid storage unit via the liquid supply channel. A liquid supply part that can be supplied to the part, circulates the liquid between the pocket and the liquid storage part, and stirs the liquid accumulated in the pocket by the liquid discharged from the liquid discharge part It is characterized by comprising a possible liquid supply stirring device.
According to this configuration, since the liquid is circulated and the liquid accumulated in the pocket is agitated, it is possible to suppress the precipitation of foreign substances collected below the inner peripheral edge. In this state, by using an external suction device or the like, it is possible to remove the collected foreign substances while floating, so that the foreign substances can be easily removed.

The liquid supply channel has a suction port that opens into the liquid storage part and sucks the liquid, and is a filter that is provided at the suction port and that can capture foreign matter sucked into the liquid supply part. It comprises a part.
According to this configuration, since the filter unit that captures the foreign matter is provided, the foreign matter that has flowed into the pocket can be removed while circulating the liquid.

Moreover, it is provided with the mesh member which is provided in the at least bottom face of the said pocket, and can capture the foreign material contained in the said liquid.
According to this configuration, since the mesh member capable of capturing the foreign matter is provided on at least the bottom surface of the pocket, the foreign matter that has sunk toward the bottom surface of the pocket can be captured.

Further, in the method for using the work platform unit according to any one of the above, a shielding step of shielding the interior of the nozzle tube base from an internal space of the container body using the shielding device, and the elastic ring A liquid spraying step of spraying the liquid to the nozzle tube base side of the body, a suction removing step of sucking and removing the liquid accumulated in the pocket and foreign matters contained in the liquid, and after the suction removing step A contact release process for releasing the contact of the elastic ring body with respect to the periphery of the open end of the nozzle tube base, and a straw-like suction nozzle is used in the suction removal process.
According to this configuration, since the straw-like suction nozzle is used in the suction removal process, it is difficult for air to be mixed in with the suction of the liquid. Thereby, the liquid and the foreign matter can be easily sucked, and the liquid and the foreign matter can be easily removed.

In the suction removal step, the liquid and the foreign matter are sucked while irradiating the liquid accumulated in the pocket with ultrasonic waves.
According to this configuration, since the liquid and the foreign matter are sucked while irradiating the ultrasonic wave in the suction removing process, the foreign matter slightly shakes and floats by the ultrasonic wave. Thereby, a foreign material can be removed easily.

Further, a shielding step of shielding the interior of the nozzle tube base from the internal space of the container body using the shielding device, a liquid spraying step of spraying the liquid to the nozzle tube side of the elastic ring body, The suction removal step of sucking and removing the liquid accumulated in the pocket and the foreign matter contained in the liquid, and releasing the adhesion of the elastic ring body to the periphery of the opening end of the nozzle nozzle after the suction removal step A close contact releasing step, wherein the mesh member is removed from the pocket between the suction removing step and the close contact releasing step.
According to this configuration, since the mesh member is removed from the pocket between the suction removing step and the close contact releasing step, the foreign matter captured by the mesh member is removed together with the mesh member. Thereby, a foreign material can be removed easily and it can prevent that a foreign material falls into the inside of a container trunk.

Further, a shielding step of shielding the interior of the nozzle tube base from the internal space of the container body using the shielding device, a liquid spraying step of spraying the liquid to the nozzle tube side of the elastic ring body, The suction removal step of sucking and removing the liquid accumulated in the pocket and the foreign matter contained in the liquid, and releasing the adhesion of the elastic ring body to the periphery of the opening end of the nozzle nozzle after the suction removal step An adhesion release step, and a curing agent is allowed to flow in the pocket and the curing agent is cured between the suction removal step and the adhesion release step.
According to this structure, since a hardening | curing agent is poured into a pocket and it hardens | cures between a suction removal process and an adhesion release process, a foreign material is restrained by a mesh. Thereby, a foreign material can be prevented from falling into the internal space of the container body in the adhesion release step.

  According to the work gantry unit according to the present invention, it is possible to prevent foreign matter from falling into the container body when the liquid is sprayed inside the nozzle tube base in the operation on the container body of the nuclear pressure vessel.

  Moreover, according to the usage method of the work cradle unit concerning this invention, it can prevent more reliably that a foreign material falls into the inside of a container trunk | drum.

It is a whole perspective view which shows the work outline | summary with respect to the reactor pressure vessel 1 which concerns on 1st embodiment of this invention. It is a principal part longitudinal cross-sectional view of the work cradle unit 10 which concerns on 1st embodiment of this invention. FIG. 3 is an enlarged cross-sectional view of a main part I in FIG. 2 in the work platform unit 10 according to the first embodiment of the present invention. FIG. 3 is an enlarged perspective view of a main part I in FIG. 2 in the work platform unit 10 according to the first embodiment of the present invention. In the work gantry unit 10 which concerns on 1st embodiment of this invention, it is the II-II arrow directional view in FIG. FIG. 6 is a cross-sectional view taken along line III-III in FIG. 5 in the work platform unit 10 according to the first embodiment of the present invention. FIG. 3 is a perspective view showing the extended shielding device 30 in the work gantry unit 10 according to the first embodiment of the present invention. In work platform unit 10 concerning a first embodiment of the present invention, it is a sectional view showing shielding device 30 in an extension state. FIG. 3 is an enlarged cross-sectional view showing a state in which the elastic ring body 30 is in close contact with the periphery of the opening end 3a of the nozzle 3 in the work gantry unit 10 according to the first embodiment of the present invention. FIG. 3 is an enlarged cross-sectional view of a main part illustrating a suction removal process in the work gantry unit 10 according to the first embodiment of the present invention. It is the principal part expanded sectional view which showed the usage method of the work stand unit 10 which concerns on 2nd embodiment of this invention. It is a principal part expanded sectional view of 10 A of work cradle units which concern on 3rd embodiment of this invention. It is a principal part expanded sectional view of the work cradle unit 10B which concerns on 4th embodiment of this invention. It is a principal part expanded sectional view which shows the usage method of the work cradle unit 10C which concerns on 5th embodiment of this invention. It is a principal part expanded sectional view which shows the modification of the usage method of the work cradle unit 10C which concerns on 6th embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
"First embodiment"
"Reactor pressure vessel"
FIG. 1 is an overall perspective view showing an outline of work on the reactor pressure vessel 1 according to the first embodiment of the present invention.
The reactor pressure vessel 1 is composed of an upper lid (not shown) and a vessel body 2 and accommodates a core structure (not shown) therein. The operation shown in FIG. 1 is performed with the upper lid and the core structure removed from the container body 2.

The container body 2 has a side peripheral wall 2a surrounding the core structure and a bottom (not shown) provided at the lower part of the side peripheral wall 2a, and is closed by an upper lid (not shown) on the upper side of the side peripheral wall 2a. An upper opening 2b is formed.
As shown in FIG. 1, the container body 2 is provided with three sets of an inlet nozzle 3 </ b> A and an outlet nozzle 3 </ b> B as a nozzle (nozzle nozzle) 3. The inlet nozzle 3 </ b> A and the outlet nozzle 3 </ b> B are formed to protrude from the side peripheral wall 2 a to the outer side of the container body 2, and are connected to the pipe 5. More specifically, each inlet nozzle 3A is connected to an inflow pipe (pipe) 5A that allows cooling water to flow in, and each outlet nozzle 3B is connected to a discharge pipe (pipe) 5B that discharges cooling water. Yes. With this configuration, the cooling water can be taken into the container body 2 from each set of the inlet nozzles 3A, and the cooling water can be discharged from the outlet nozzles 3B. In addition, as compared with the inlet nozzle 3A, the outlet nozzle 3B gradually decreases in cross-sectional shape from the opening end 3a that opens to the inner peripheral surface of the side peripheral wall 2a toward the pipe 5.
The operation in FIG. 1 reinforces the welded portion between the nozzle 3 and the pipe 5.

"Working platform unit"
The work gantry unit 10 includes a container body 11, an opening / closing device 21, and a shielding device (not shown in FIG. 1, see FIG. 2) 30.
As shown in FIG. 1, above the container body 2, there is a work floor 4 for making preparations for introducing materials and equipment into the container body 2 and for making preparations for workers to enter as necessary. Is provided. In the work floor 4, a communication hole 4 a that communicates vertically is formed at a position where the container body 2 is disposed immediately below the work floor 4. Since the bottomed substantially cylindrical container body 11 is disposed from the communication hole 4a to the inside of the container body 2, the container body 11 can be moved from the work floor 4 to the container body in an air atmosphere even when the outside is filled with cooling water. It is possible to supply materials and equipment to the inside of 2 or arrange workers.

  Further, as shown in FIG. 1, the container body 11 is located at the bottom of the container body 11 and is disposed inside the container body 2, and the work floor 4 above the platform 12 and the container body 2. And a substantially cylindrical connecting pipe (tubular body) 13.

The platform 12 has an outer diameter smaller than the inner diameter of the container body 2, and has a substantially cylindrical partition wall 12a facing the inner wall surface 2e of the side peripheral wall 2a with a gap, and a wall bottom 12b closing the lower end of the partition wall 12a. And a flange 12c that protrudes from the upper end of the partition wall 12a to the outer peripheral side and is supported by the upper edge of the container body 2. The platform 12 is fixed to the upper opening 2b of the container body 2 using a fixing hole 12d formed in the flange 12c.
With such a configuration, the platform 12 has a working chamber 12A partitioned from the internal space 2A of the container body 2 by the partition wall 12a and the wall bottom 12b.

  The connection pipe 13 has a lower end fixed to the flange 12 c of the platform 12, and the partition wall 11 a of the container body 11 is constituted by the partition wall 12 a of the platform 12 and the connection pipe line 13. The bottom part 11b of the container body 11 is comprised by 12b. Between the flange 12c of the platform 12 and the upper end of the container body 2, and between the flange 12c of the platform 12 and the lower end of the connecting pipe line 13, the inside of the container body 2 is sealed. Even if the water is drained so that the water level is lower than the table 3, the cooling water filled around the connection pipe line 13 above the container body 2 leaks into the container body 2 and the container body 11. There is no end to it.

In addition, an access window 15 is formed in the partition wall 12a of the platform 12 to communicate the inside of each nozzle 3 with the work chamber 12A.
Further, on the wall bottom 12 b, a moving device 16 is provided for putting materials and equipment into the nozzle 3 through the access window 15. Various mechanisms can be applied as the moving device 16, for example, a manipulator configured with a multi-joint, a slide mechanism that can be expanded and contracted, and the like.
In the work chamber 12 </ b> A, an opening / closing device 21 for opening and closing each access window 15 is provided for each access window 15.

  2 is a longitudinal sectional view of a main part of the work gantry unit 10, and FIG. 3 is an enlarged sectional view of a main part I in FIG. 2 and 3, the moving device 16 provided in the working chamber 12A and the like are omitted for easy understanding of the configuration of the opening / closing device 21.

  As shown in FIG. 2, the opening / closing device 21 includes a substantially plate-like lid body 22 provided corresponding to each access window 15 on the inner circumferential surface of the partition wall 12a, and the lid body 22 as an inner circumferential surface of the partition wall 12a. A pair of guide rails 23 that are slid between and guided to be slidable in the vertical direction, and a moving means that is provided above the access window 15 and slides the lid body 22 in the vertical direction along the guide rails 23. An electric winch 24 and a pair of support members 25 spanned between a pair of guide rails 23 at the upper and lower portions of the access window 15 are provided. Although not shown, a motor or the like serving as a drive unit of the electric winch 24 is connected to a control device provided on the work floor 4, and is unwound and wound under the control of the control device to perform the lid 22. Can be moved in a vertical direction from a closed position A where the access window 15 is closed to an open position B where the access window 15 is opened.

  As shown in FIG. 3, the surfaces of the pair of guide rails 23 and the pair of support members 25 facing the partition wall 12 a are advanced and retracted toward the lid 22 disposed so as to close the access window 15. A hydraulic cylinder 26 that is a pressing means that can be pressed against the platform 12 is provided, and the lid 22 is pressed toward the partition wall 12a by the hydraulic cylinder 26 so that the access window 15 extends inward. The O-ring 22a disposed on the inner flange 15a is elastically deformed, so that even if the outside of the platform 12 is an underwater environment, water enters the work chamber 12A via the access window 15. To prevent this more reliably.

"Shielding device"
4 is an enlarged perspective view of the main part I in FIG. 2, FIG. 5 is a sectional view taken along line II-II in FIG. 2, and FIG. 6 is a sectional view taken along line III-III in FIG.
As shown in FIGS. 3 to 6, the shielding device 30 is attached to the access window 15 of the partition wall 12 a in order to shield the interior of the nozzle 3 from the internal space 2 </ b> A of the container body 2.

  As shown in FIGS. 3 and 4, the shielding device 30 includes a telescopic cylinder body 38 in which a cylinder axis P is superimposed on the central axis of the access window 15, and two upper and lower positions of the telescopic cylinder body 38 as shown in FIG. The hydraulic cylinder 34 provided, guide mechanisms 35 provided at two left and right positions of the telescopic cylinder 38, and an elastic ring body 36 provided at the distal end of the telescopic cylinder 38 in the cylinder axis direction are provided.

  As shown in FIGS. 3 and 4, the telescopic cylinder 38 includes a perforated substrate 31 fixed to the partition wall 12 a, a bellows ring 32 whose cylindrical axial base end portion 32 a is fixed to the perforated substrate 31, and And a rigid ring 33 fixed to the front end of the bellows ring 32 in the cylinder axis direction.

  The perforated substrate 31 is a member formed in an annular plate shape, and a circular hole 31a passes through the center of the plate surface. The perforated substrate 31 is fixed in a state where the plate surface is in close contact with the outer surface of the inner flange 15 a extending inward in the access window 15. The perforated substrate 31 is preferably formed of stainless steel, for example.

The bellows ring 32 is made of a flexible material, and is formed in a bellows shape so that irregularities are continuous in the axial direction on the entire outer periphery. As shown in FIGS. 4 and 6, the bellows ring 32 has the entire outer periphery of the base end portion 32 a (the radially inner side of the container body 11) of the inner periphery of the circular hole 31 a of the perforated substrate 31. It is fixed airtight around the circumference.
The bellows ring 32 is preferably formed of, for example, silicon rubber.

The rigid ring 33 is made of a rigid body such as metal, and as shown in FIG. 6, a cylindrical portion 33a surrounding the distal end side of the outer peripheral portion of the bellows ring 32, and an outer flange portion 33b extending from the outer periphery of the distal end of the cylindrical portion 33a. And have.
In the inner peripheral portion of the cylindrical portion 33a, the entire outer peripheral portion of the distal end portion 32b (the radially outer side of the container body 11) of the bellows ring 32 is airtightly fixed to the entire periphery at the intermediate position in the cylindrical axis direction. Yes.
As shown in FIG. 6, the outer flange portion 33 b has a cross-sectional contour of the covering tip end surface 33 c in each cross section orthogonal to the vertical direction, with the cylinder axis P overlapped in the axial direction. It is line-symmetrically formed and substantially the same as the curvature of the inner wall surface 2e of the side peripheral wall 2a (see FIG. 8).
The rigid ring 33 is preferably formed of stainless steel, for example.

  As shown in FIGS. 4 and 5, for example, three hydraulic cylinders 34 are provided in each of the upper and lower portions of the shielding device 30, and the base ends thereof are provided as shown in FIGS. 4 and 6. While being connected to the hole substrate 31, the tip thereof is connected to the outer flange portion 33 b of the rigid ring 33. Similar to the hydraulic cylinder 26, the hydraulic cylinder 34 is connected to a working water supply device connected to a control device provided on the work floor 4 by piping (not shown), and is operated under the control of the control device. It is possible to advance and retreat by driving the supply device.

  As shown in FIGS. 5 and 6, the guide mechanism 35 includes an outer peripheral portion of the cylindrical portion 33 a and an L-shaped member 35 a fixed to the perforated substrate 31 in each of the left and right portions of the shielding device 30. The slider member 35b is connected and schematically configured. More specifically, in each guide mechanism 35, rail portions that are opposed to each other and extend in the cylinder axis direction are formed on the outer peripheral portion of the cylindrical portion 33a and the L-shaped member 35a, and this rail portion is formed as a slider member 35b. Are slidably coupled so that the rigid ring 33 is guided in the cylinder axis direction.

"Elastic ring body"
As shown in FIG. 6, the elastic ring body 36 is formed in an annular shape when viewed in the cylinder axis direction, and has substantially the same thickness. As shown in FIG. 6, the elastic ring body 36 has a cross-sectional contour in each cross section perpendicular to the vertical direction when the cylinder axis P is viewed in the axial direction, like the covering tip surface 33 c of the outer flange portion 33 b. Further, it is symmetrical with respect to the cylinder axis P and is substantially the same as the curvature of the inner peripheral surface of the partition wall 12a.
The elastic ring body 36 is affixed to the entire surface of the coated front end surface 33c of the outer flange portion 33b of the rigid ring 33 by an adhesive (for example, silicon), and covers the entire surface of the coated front end surface 33c. The elastic ring body 36 is preferably formed of, for example, a closed cell silicon sponge.
The elastic ring body 36 functions as a cushioning material for the rigid ring 33 pressed against the side peripheral wall 2 a of the container body 2 and a sealing material for the telescopic cylinder 38.

As shown in FIG. 3, a pocket 37 is formed on the ring-shaped tip surface 36 a of the elastic ring body 36 facing the periphery of the opening end 3 a of the nozzle 3.
As shown in FIG. 5, the pocket 37 is formed in a notch shape on the lower side of the inner peripheral edge of the ring-shaped tip surface 36a as shown in FIG. As shown in FIG. 6, the pocket 37 extends from the lowermost part of the inner peripheral edge to both sides in the circumferential direction, and the linear dimension connecting both ends is about 50% of the inner diameter of the elastic ring body 36. Yes. The cross-sectional shape intersecting the circumferential direction of the pocket 37 is such that the bottom surface 37a extending in the cylinder axis direction from the ring-shaped tip surface 36a intersects with the ring-shaped tip surface 36a extending in the radial direction from the inner peripheral surface. It has a shape to be formed.
Note that the circumferential length and cross-sectional shape of the pocket 37 can be changed as appropriate according to the amount of liquid W and the liquid level, which will be described later.

  The surface of the elastic ring body 36 is coated with a silicon-based sealant including the pockets 37 to close the fine pores on the surface of the elastic ring body 36.

  Next, the basic operation of the work gantry unit 10 and the reinforcement process for the joint between the nozzle 3 and the pipe 5 will be described. In FIG. 1, when working inside the container body 2, the work floor 4 is first installed. Next, the platform 12 and the connection pipe line 13 are assembled on the work floor 4 to construct the container body 11. Further, the above opening / closing device 21 is installed inside, and the lid 22 is set to the closed position A (see FIG. 2), and the access window 15 is closed by being pressed by the hydraulic cylinder 26. Further, the shielding device 30 is installed around the access window 15, the hydraulic cylinder 34 of the shielding device 30 is reduced, and the bellows ring 32 is reduced (see FIGS. 3 and 4).

  Then, the constructed container body 11 is suspended by a crane or the like, and the portion of the platform 12 is inserted into the interior of the container body 2 until the flange 12c comes into contact with the upper end of the container body 2. An air environment can be created in the working chamber 12A while the cooling water is filled. Further, the space between the container body 2 and the platform 12 and the space outside the connection pipe line 13 which is the space above the container body 2 can be sealed with the flange 12c. For this reason, the space outside the connection pipe line 13 can be lowered only in the container body 2 until the water level is below the nozzle 3 while the cooling water is filled. The outside can also be in the air.

  In this case, when the platform 12 described above is inserted or before the platform 12 is brought into the air environment, the access window 15 and the shielding device 30 are opposed to the opening end 3a of the nozzle 3.

  Next, the hydraulic pressure of the hydraulic cylinder 34 in the shielding device 30 is increased to extend the hydraulic cylinder 34 (see FIGS. 7 and 8). Then, the rigid ring 33 is displaced in the cylinder axis direction toward the radially outer side of the container body 11 while being guided in the cylinder axis direction by the guide mechanism 35. As the guide mechanism 35 is displaced, the bellows ring 32 gradually expands. Then, as shown in FIGS. 7 and 8, the elastic ring body 36 that covers the coating tip surface 33c of the rigid ring 33 comes into contact with the periphery of the opening end 3a of the nozzle 3 in the partition wall 12a.

  Then, as shown in FIG. 9, the rigid ring 33 presses the elastic ring body 36 (for example, 10 tf≈98100 N), so that the elastic ring body 36 is elastically deformed and around the opening end 3 a of the nozzle 3. In close contact. In this way, the inside of the nozzle 3 is shielded from the internal space of the container body 2 by the shielding device 30 (shielding process).

  Next, first, the hydraulic pressure of the hydraulic cylinder 26 is decreased to release the state in which the lid 22 is pressed against the platform 12, and then the electric winch 24 is driven to move the lid 22 from the closed position A to the open position B. And the access window 15 is opened (see FIG. 2).

In this way, the reinforcement process is performed on the connection portion between the nozzle 3 and the pipe 5 by the manipulator accommodated in the platform 12. As an example of this reinforcement processing, ultrasonic nondestructive inspection work, decontamination work inside the nozzle 3 by shot blasting, cutting work of the connection part, cleaning work inside the nozzle 3, welding work such as TIG welding This is done in order. At this time, in the ultrasonic inspection work, the coplanar is sprayed, and in the cleaning work, the cleaning water is sprayed on the work site (liquid spraying process). The sprayed liquid (casplant and washing water) W causes foreign matter D such as a projection material and chips used for shot blasting to flow toward the platform 12. The flowed liquid W and foreign matter D are recovered by a liquid recovery device disposed in the work chamber 12A and pumped to the work floor 4.
After all of the above operations are completed, the liquid W and the foreign matter D stored in the pocket 37 of the elastic ring body 36 are removed by suction with a suction device disposed in the working chamber 12A (suction removal step), and all reinforcements are performed. The process ends.

When removing the container body 11, the procedure is reversed.
That is, the electric winch 24 of the opening / closing device 21 is driven to slide the lid 22 downward from the open position B to the closed position A along the inner peripheral surface of the platform 12. Next, the hydraulic pressure of the hydraulic cylinder 26 is raised and advanced toward the lid body 22, thereby pressing the lid body 22 against the platform 12, thereby closing the access window 15.

Then, the hydraulic pressure of the hydraulic cylinder 34 is reduced to reduce the hydraulic cylinder 34. If it does so, the state which closely_contact | adhered to the circumference | surroundings of the opening end 3a of the nozzle 3 will be cancelled | released (adhesion release process). The rigid ring 33 is displaced toward the radially inward side of the container body 11 while being guided in the cylinder axis direction by the guide mechanism 35. In this manner, the rigid ring 33 is retracted toward the partition wall 12a, and the bellows ring 32 is reduced.
Finally, after recovering the water level inside the container body 2, the container body 11 is pulled up.
The above is the basic operation of the work gantry unit 10 and the method of reinforcing the nozzle 3.

Next, the operation of the pocket 37 will be described.
As shown in FIGS. 7 and 8, when the elastic ring body 36 is pressed around the open end 3a of the nozzle 3 by the rigid ring 33, the elastic ring body 36 is elastically deformed as shown in FIG. Specifically, a pocket 37 is formed on the lower side of the inner peripheral edge of the ring-shaped tip surface 36a, so that a sectional view is formed between the periphery of the opening end 3a of the nozzle 3 and the elastic ring body 36. A trapezoidal groove is formed. On the other hand, at the portion where the pocket 37 is not formed in the inner peripheral edge of the ring-shaped tip surface 36a, the ring-shaped tip surface 36a is deformed so that the center side of the inner peripheral portion of the elastic ring body 36 is raised (in FIG. A groove having a triangular shape in sectional view is formed between the periphery of the opening end 3a of the nozzle 3 and the elastic ring body 36).

  As described above, in the reinforcement process, coplanar and washing water (hereinafter collectively referred to as “liquid W”) is flowed and collected on the platform 12 side, and the nozzle 3 is transferred to the liquid collecting device of the platform 12. The liquid W flows toward it. More specifically, as shown in FIG. 9, from the position where the liquid W is sprayed, the inner ends of the opening end 3 a of the nozzle 3, the elastic ring body 36, the rigid ring 33, the bellows ring 32, and the perforated substrate 31. The liquid W flows along with the foreign matter D with the lower side of the periphery directed toward the platform 12.

  The liquid W flowing from the nozzle 3 into the elastic ring body 36 flows into the pocket 37 at one end, is collected below the pocket 37, and flows out to the bellows ring 32 side. At this time, the foreign substance D flowing into the pocket 37 accompanying the liquid W moves downward in the liquid W stored in the pocket 37, and most of the foreign substance D flows out to the bellows ring 32 side together with the liquid W. It is recovered by the liquid recovery device.

  When the spraying of the liquid W is stopped, the foreign matter D collected below the pocket 37 is uniformly deposited on the bottom surface 37 a of the pocket 37. At this time, the foreign matter D is collected below the pocket 37, so that the foreign matter is not contained in the concave gap S formed between the elastic ring body 36 and the periphery of the opening end 3 a of the nozzle 3 except under the pocket 37. D hardly penetrates.

Finally, on the lower side of the pocket 37, the foreign matter D uniformly deposited on the bottom surface is removed by suction with the liquid W through the suction nozzle of the suction device 40. At this time, since the liquid W is stored in the pocket 37, the foreign matter D that has entered the concave gap S along with the suction of the liquid W can be sucked, and the foreign matter D can be easily sucked by the suction device 40. .
In this manner, after removing all the foreign matter D and the liquid W from the pocket 37, the contact state of the elastic ring body 36 is released.

  As described above, according to the present embodiment, the pocket 37 formed on the ring-shaped tip surface 36a of the elastic ring body 36 guides the foreign matter D that has flowed into the lower part of the inner peripheral edge, so that the foreign matter D gathers downward. . Thereby, the foreign substance D which penetrates into the concave gap S formed between the elastic ring body 36 and the periphery of the opening end 3a of the nozzle 3 can be concentrated below the inner peripheral edge.

Further, for example, in the configuration in which the pocket 37 is omitted (see the upper portion of the inner peripheral edge of the ring-shaped tip surface 36a in FIG. 9), the tube is deformed so that the center side of the inner peripheral portion of the elastic ring body 36 rises, and the tube A groove having a triangular shape in cross section is formed between the periphery of the table 3 and the elastic ring body 36. In this case, the foreign matter D easily collects at the groove tip, and the foreign matter D easily enters the concave gap S formed continuously at the groove tip.
On the other hand, according to the configuration of the present embodiment, the pocket 37 is formed to suppress the deformation of the center side of the inner peripheral portion of the elastic ring body 36, and the foreign matter D is uniformly formed on the widely formed bottom surface 37a. Since the foreign matter D is less likely to collect in the concave gap S by precipitating the slag, the ratio of the foreign matter D entering the concave gap S can be reduced.

  Accordingly, the range of the concave gap S through which the foreign substance D enters can be limited, and the ratio of the foreign substance D entering the concave gap S can be reduced, so that the foreign substance D can be easily collected. Therefore, it is possible to prevent the foreign matter D from falling into the internal space 2 </ b> A of the container body 2 when the close contact of the elastic ring body 36 with the periphery of the opening end 3 a of the nozzle 3 is released.

"Second embodiment"
Next, a second embodiment of the present invention will be described. In each embodiment described below, common constituent elements are denoted by the same reference numerals and description thereof is omitted.

FIG. 11 is an explanatory diagram of a method of using the work platform unit 10 according to the second embodiment of the present invention.
As shown in FIG. 11, the present embodiment differs from the first embodiment described above in that a straw-shaped suction nozzle 61 and an ultrasonic irradiation device 62 are used in the suction removal process described above.

  First, after stopping the spraying of the liquid W, a manipulator or the like irradiates ultrasonic waves mainly on the bottom surface 37 a of the pocket 37 by using the ultrasonic irradiation device 62. By this ultrasonic irradiation, the foreign matter D slightly vibrates and floats in the liquid W.

  Next, a manipulator or the like sucks the liquid W and the foreign matter D collected in the pocket 37 by using the straw-like suction nozzle 61 in a state where the ultrasonic wave is irradiated. In this suction, since the opening area of the suction nozzle 61 is sufficiently small with respect to the pocket 37, it is difficult for air to be mixed into the suction nozzle 61 as the liquid W is sucked. For this reason, pressure loss due to air mixing does not occur, the suction force of the suction nozzle 61 does not decrease, and the liquid W and the foreign matter D are smoothly sucked.

As described above, according to the present embodiment, since the straw-shaped suction nozzle 61 is used in the suction removal process, it is difficult for air to be mixed in with the suction of the liquid W. Thereby, the liquid W and the foreign material D can be easily sucked, and the liquid W and the foreign material D can be easily removed.
In addition, since the liquid W and the foreign matter D are sucked while irradiating ultrasonic waves in the suction and removal process, the foreign matter D is slightly shaken by the ultrasonic waves and is not easily precipitated. Thereby, the liquid W and the foreign material D can be easily removed.

  In the present embodiment, the suction nozzle 61 and the ultrasonic irradiation device 62 are used in combination, but only one of them may be used for the suction removal operation.

"Third embodiment"
Subsequently, a third embodiment of the present invention will be described.
FIG. 12 is an enlarged cross-sectional view of a main part of a work platform unit 10A according to the third embodiment of the present invention.
The work gantry unit 10 </ b> A includes a gas supply stirring device 70 having an air supply pipe (gas supply flow path) 71 and a compressor 72 connected to the air supply pipe 71.

A part of the air supply pipe 71 is embedded in the elastic ring body 36 and the rigid ring 33, and an opening end (gas discharge portion) 71 a at one end in the longitudinal direction opens below the side surface 37 b of the pocket 37. The open end 71b at the other end is connected to the compressor 72 disposed on the platform 12 side.
The open end 71 a of the air supply pipe 71 is open to the lower side of the side surface 37 b at the lowermost portion of the pocket 37.

  The gas supply stirring device 70 having the above-described configuration is configured so that the compressor 72 supplies air G to the air supply pipe 71 in the liquid spraying process or the suction removing process, so that the opening end with respect to the liquid W accumulated in the pocket 37 is opened. Air G is discharged from 71a. The air G discharged from the open end 71a stirs the liquid W and causes the foreign matter D to float. Then, the air G in which the liquid W is stirred is discharged from the pocket 37 to the inside of the nozzle 3 or the shielding device 30.

According to the present embodiment, the air G discharged from the opening end 71a agitates the liquid W accumulated in the pocket 37, thereby preventing the foreign matter D from being precipitated. In this state, the foreign substance D can be easily removed by removing the liquid W and the foreign substance D in the pocket 37 using the suction device 40.
Moreover, since the air G which stirred the liquid W is discharged | emitted to the inside of the nozzle 3 or the obstruction | occlusion apparatus 30, it is not necessary to process the supplied air G. Thereby, the apparatus configuration can be relatively simplified.

Note that the opening position of the opening end 71a of the air supply pipe 71 may be opened to another position of the pocket 37 on the condition that the liquid W can be stirred.
Alternatively, the liquid W may be agitated by discharging a gas other than the air G to the liquid W.
Further, a needle member or the like may be provided at the open end 71 a of the air supply pipe 71.

"Fourth embodiment"
Subsequently, a fourth embodiment of the present invention will be described.
FIG. 13 is an enlarged cross-sectional view of a main part of a work platform unit 10B according to the fourth embodiment of the present invention.
The work platform unit 10 </ b> B includes a liquid supply pipe (liquid supply flow path) 81, a pump (liquid supply section) 82 connected to the liquid supply pipe 81, a liquid discharge pipe (liquid discharge flow path) 83, and a platform 12. The liquid supply stirring apparatus 80 which has the liquid storage tank (liquid storage part) 84 set | placed in the working chamber 12A is provided.

The liquid supply pipe 81 has substantially the same configuration as the air supply pipe 71, but an opening end 81 b at the other end opens into the liquid storage tank 84, and an opening end (liquid discharge portion) 81 a and an opening end 81 b The difference is that a pump 85 is disposed between the two. Further, a filter (filter part) 86 capable of capturing the foreign matter D is attached to the opening end 81b.
The liquid discharge pipe 83 is routed between the upper side surface 37 b of the pocket 37 and the liquid storage tank 84, and extends along the inner peripheral portions of the elastic ring body 36, the bellows ring 32, and the perforated substrate 31. ing.

In the liquid supply stirring device 80 having the above-described configuration, the pump 85 supplies the liquid W from the liquid storage tank 84 to the pocket 37 via the liquid supply pipe 81 in the liquid spraying process or the suction removing process of the liquid W. To do. Then, the liquid W discharged from the open end 71a stirs the liquid W collected in the pocket 37, and causes the foreign matter D to float.
On the other hand, the liquid W collected in the pocket 37 is discharged to the liquid storage tank 84 through the liquid discharge pipe 83, and the liquid W circulates. As the liquid W circulates, the filter 86 provided at the open end 81b of the liquid supply pipe 81 captures the foreign matter D, so that the foreign matter D in the pocket 37 is reduced.

  According to this embodiment, in addition to obtaining the main effects of the above-described third embodiment, the liquid W can be circulated and reused, and the air bubbles are ruptured compared to the case where the air G is supplied. Therefore, there is no possibility that the foreign matter D is scattered. Thereby, the foreign material D can be further easily collected.

In addition, since the filter 86 that captures the foreign matter D is provided, the foreign matter D can be prevented from circulating in the pocket 37, and the foreign matter D can be easily collected.
Further, by circulating the liquid W in the liquid spraying process, the trouble of removing the foreign matter D during the liquid removing process can be omitted.
Moreover, even if the liquid W is not circulated in the liquid spraying process, the trouble of removing the foreign matter D is reduced by circulating the liquid W during the liquid removing process.

"Fifth embodiment"
Subsequently, a fifth embodiment of the present invention will be described.
FIG. 14 is an explanatory diagram of a method of using the work platform unit 10C according to the fifth embodiment of the present invention.
As shown in FIG. 14A, the work platform unit 10C is different from the configuration of the first embodiment described above in that the mesh member 90 is adhered to the bottom surface 37a and the side surface 37b of the pocket 37.
The mesh member 90 is formed so that the roughness of the mesh is smaller than that of the foreign matter D, and is configured to be able to capture the foreign matter D. The mesh member 90 is attached to the pocket 37 with, for example, a silicon-based adhesive.

  In the work platform unit 10C, the mesh member 90 captures the foreign matter D that sinks mainly toward the bottom surface 37a in the liquid spraying step and the suction removal step shown in FIG. 14B, the manipulator or the like peels off the mesh member 90 from the bottom surface 37a and the side surface 37b of the pocket 37 and removes it as shown in FIG. 14C. Finally, as shown in FIG. 14 (d), an adhesion release step is performed to separate the elastic ring body 36 from the periphery of the nozzle 3.

  According to this configuration, the foreign material D sinking to the bottom surface 37 a of the pocket 37 and the foreign material D entering the gap S are captured by the mesh member 90. And the foreign material D is removed with the mesh member 90 by removing the mesh member 90 before an adhesion cancellation | release process. Thereby, the foreign material D can be easily removed, and the foreign material D can be prevented from falling into the internal space 2 </ b> A of the container body 2 in the adhesion release process.

  In the present embodiment, the mesh member 90 is also attached to the side surface 37b. However, since the foreign matter D adhering to the side surface 37b is small, the mesh member 90 attached to the side surface 37b may be omitted.

FIG. 15 is a modification of the method of using the work platform unit 10C in the present embodiment.
As shown in FIG. 15, in this modification, the foreign material D is captured by the mesh member 90 in the liquid spraying step and the suction removing step shown in FIG. Then, after the suction removal step shown in FIG. 14B, as shown in FIG. 15A, a manipulator or the like pours a hardener K (for example, silicon-based) that can flow into the pocket 37. Finally, as shown in FIG. 14 (d), after the curing agent K is cured, the mesh member 90 is subjected to an adhesion release process to separate the elastic ring body 36 from the periphery of the nozzle 3.

  According to this configuration, the foreign material D sinking to the bottom surface of the pocket 37 and the foreign material D entering the gap S are captured by the mesh member 90. And the foreign material D is restrained by the mesh member 90 by hardening | curing the hardening | curing agent K before an adhesion cancellation | release process. Thereby, it is possible to prevent the foreign matter D from falling into the internal space 2 </ b> A of the container body 2 during the close contact releasing process.

  Note that the operation procedure shown in the above-described embodiment, various shapes and combinations of the constituent members, and the like are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the embodiment described above, various operations are performed using a manipulator or the like, but an operator may perform various operations instead of the manipulator.

DESCRIPTION OF SYMBOLS 1 ... Reactor pressure vessel 2 ... Container body 2A ... Internal space 2a ... Side peripheral wall 2b ... Upper opening 2e ... Inner wall surface 3 ... A nozzle (nozzle nozzle)
3a ... Open ends 10, 10A, 10B, 10C ... Work platform unit 12 ... Platform (frame)
12A ... Work chamber 12a ... Partition wall 12b ... Wall bottom 15 ... Access window 36 ... Elastic ring body 36a ... Ring-shaped tip surface 37 ... Pocket 37a ... Bottom surface 38 ... Telescopic cylinder 61 ... Suction nozzle 62 ... Ultrasonic irradiation device 70 ... Gas Supply stirrer 71 ... Air supply pipe (gas supply flow path)
71a ... Open end (gas discharge part)
72. Compressor (gas supply unit)
80 ... Liquid supply stirring device 81 ... Liquid supply piping (liquid supply flow path)
81a ... Open end (liquid discharge part)
83 ... Liquid discharge pipe (liquid discharge flow path)
84 ... Liquid reservoir (liquid reservoir)
85 ... Pump (liquid supply part)
86: Filter (filter part)
90 ... Mesh member D ... Foreign matter G ... Air (gas)
K ... Curing agent P ... Tube axis W ... Liquid

Claims (9)

It has a side wall surrounding the periphery of the core structure and a bottom provided at the lower part of the side wall, and is used for the operation of the reactor body of the reactor pressure vessel in which the upper opening of the side wall is closed by an upper lid, A work platform unit capable of working inside a nozzle tube formed to protrude from the side peripheral wall to the outer side of the container body,
A cylinder extending from above the container body toward the upper opening of the container body;
A partition provided at a lower portion of the cylindrical body and facing the inner wall surface of the side peripheral wall with a gap in an inner space of the container body, and a wall bottom provided at a lower portion of the partition wall from the inner space of the container body. A partitioned working chamber is defined, and a platform in which an access window facing the opening end of the nozzle nozzle formed on the inner wall surface of the side peripheral wall is formed in the partition wall;
A telescopic telescopic cylinder provided in the access window and extending toward the opening end of the nozzle base, and provided at a tip of the telescopic cylindrical body in the cylinder axial direction, around the opening end of the nozzle base. An elastic ring body that is pressed and in close contact, and includes a shielding device that shields the inside of the nozzle tube base from the internal space of the container body,
The elastic ring body is formed on the ring tip end surface extending in the circumferential direction on the lower side of the inner peripheral edge, and guides the liquid sprayed on the nozzle tube base side and flowing toward the mount side to the lower side of the inner peripheral edge. A work gantry unit characterized by comprising: A gas discharge part provided in the pocket and capable of discharging gas;
A gas supply flow path communicating with the gas discharge section;
A gas supply part capable of supplying the gas to the gas discharge part via the gas supply flow path;
The work gantry unit according to claim 1, further comprising a gas supply stirring device capable of stirring the liquid accumulated in the pocket by the gas discharged from the gas discharge unit. A liquid discharge passage capable of discharging the liquid accumulated in the pocket from the pocket;
A liquid reservoir capable of storing the liquid that has flowed through the liquid discharge channel;
A liquid ejection part provided in the pocket and capable of ejecting the liquid;
A liquid supply flow path communicating with the liquid discharge section and the liquid storage section;
A liquid supply part capable of supplying the liquid stored in the liquid storage part to the liquid discharge part via the liquid supply channel;
A liquid supply and agitation device is provided that circulates the liquid between the pocket and the liquid storage unit, and can agitate the liquid accumulated in the pocket by the liquid discharged from the liquid discharge unit. The work cradle unit according to claim 1 or 2. The liquid supply channel has a suction port that opens into the liquid reservoir and sucks the liquid,
The work cradle unit according to claim 3, further comprising a filter unit provided at the suction port and capable of capturing the foreign matter of the liquid sucked into the liquid supply unit.   The work gantry unit according to claim 1, further comprising a mesh member provided on at least a bottom surface of the pocket and capable of capturing a foreign matter contained in the liquid. A method for using the work platform unit according to any one of claims 1 to 5,
A shielding step of shielding the interior of the nozzle pedestal from the internal space of the container body using the shielding device;
A liquid spraying step of spraying the liquid to the nozzle tube side from the elastic ring body;
A suction removal step of sucking and removing the liquid accumulated in the pocket and foreign matter contained in the liquid;
A contact release step for releasing the contact of the elastic ring body with respect to the periphery of the opening end of the nozzle nozzle after the suction removal step;
A method of using a work gantry unit, wherein a straw-like suction nozzle is used in the suction removal step. It is a usage method of the work cradle unit of Claim 6, Comprising:
The method of using a work platform unit, wherein the suction removal step sucks the liquid and the foreign matter while irradiating the liquid accumulated in the pocket with ultrasonic waves. A method for using the work platform unit according to claim 5,
A shielding step of shielding the interior of the nozzle pedestal from the internal space of the container body using the shielding device;
A liquid spraying step of spraying the liquid to the nozzle tube side from the elastic ring body;
A suction removal step of sucking and removing the liquid accumulated in the pocket and foreign matter contained in the liquid;
A contact release step for releasing the contact of the elastic ring body with respect to the periphery of the opening end of the nozzle nozzle after the suction removal step;
A method of using a work platform unit, wherein the mesh member is removed from the pocket between the suction removal step and the adhesion release step. A method for using the work platform unit according to claim 5,
A shielding step of shielding the interior of the nozzle pedestal from the internal space of the container body using the shielding device;
A liquid spraying step of spraying the liquid to the nozzle tube side from the elastic ring body;
A suction removal step of sucking and removing the liquid accumulated in the pocket and foreign matter contained in the liquid;
A contact release step for releasing the contact of the elastic ring body with respect to the periphery of the opening end of the nozzle nozzle after the suction removal step;
A method of using a work gantry unit, wherein a curing agent is allowed to flow in the pocket and the curing agent is cured between the suction removal step and the adhesion release step.

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