JPH10156541A - Manufacturing method of super thick corrosion resistant container - Google Patents

Abstract

(57) [Problem] To provide a product in which an inner layer made of a strength material and an outer layer made of a corrosion-resistant material are integrated without gaps. SOLUTION: At the stage of factory processing, a container body 5 is formed by forming a corrosion-resistant outer layer 15 on an outer surface of a thick-strength material portion 9 for forming a container body inner layer via an intermediate layer 13, and a container lid. On the outer surface of the thick layer material portion 23 for forming the body layer,
The container lid 7 is formed by forming the corrosion-resistant outer layer 26 via the intermediate layer 25, and the groove 8 formed between the container body 5 and the container lid 7, the intermediate layers 13, 25 In contrast, the stepped discontinuous groove 3 in which the outer layers 15 and 26 of the corrosion resistant material are lowered by one step
4 are formed, and at the stage of on-site processing, the groove 8 formed between the container body 5 and the container lid 7 is weld-welded from the back side in the order of the strength material and the intermediate layer. Thereafter, the corrosion-resistant material is weld-welded on the stepped discontinuous groove 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a super-thick radioactive waste used in an overpack for radioactive waste disposal for geologically disposing radioactive waste used in a nuclear power plant or the like in a stable state. The present invention relates to a method for producing a meat corrosion-resistant container.

[0002]

2. Description of the Related Art Radioactive materials (radioactive waste, spent fuel, etc.) generated in nuclear reactors such as nuclear power plants at high, medium and low radioactivity levels are radioactive (high, medium and low).
(Low) and stored in dedicated sealed containers suitable for them, and stored and stored.

[0003] In order to isolate the radioactive waste from the living sphere by storing and disposing the radioactive waste in a deep underground layer, the radioactive waste is first vitrified to form a storage container called a vitrified body. The storage container is subjected to an overpacking process for further sealing it with a sealed container called an overpack made of metal or the like, and then the sealed container is carried into a geological disposal site, and these are disposed in a disposal hole provided in the geological disposal site. Into a container, and a geological disposal in which a buffer material such as bentonite is filled around the sealed container in the disposal hole is performed.

[0004] Since the overpack containing and sealing the vitrified body is stored in a deep underground layer for a long period of time, it is required to have high strength to withstand the earth pressure and high corrosion resistance to withstand corrosion at the same time.

[0005] Therefore, it has been studied to use an overpack as an ultra-thick corrosion-resistant container having a double structure having a thick inner layer having high strength and a thin outer layer having high corrosion resistance.

[0006] Here, the production of overpacks must be performed easily and reliably because all operations are performed by remote control in view of handling of radioactive wastes. When the material of the inner layer (for example, carbon steel) is mixed with the material of the outer layer (for example, titanium) which is a corrosion-resistant material, the weld becomes brittle or cracked. There is a condition that the welding between them must be performed while completely ensuring that the materials are not mixed.

In order to satisfy the above conditions, as shown in FIG. 5, an inner tank container 1 made of a strength material and an outer tank container 2 made of a corrosion-resistant material are separately formed, and the vitrified body is accommodated in the inner tank container 1. After sealing, an inner tank 1 is housed and sealed in the outer tank 2.

[0008]

However, the above-described super-thick corrosion-resistant container having the separate structure has the following problems.

That is, when the inner vessel 1 and the outer vessel 2 are separately prepared, and the vitrified material is housed and sealed in the inner vessel 1, the inner vessel 1 is housed and sealed in the outer vessel 2. Since it is difficult to fit the inner vessel 1 and the outer vessel 2 without a gap, a certain space 3 is created between the inner vessel 1 and the outer vessel 2.

Then, there is a possibility that the inner tank 1 may be corroded by oxygen contained in the air sealed in the space 3.

The present invention has been made in view of the above circumstances, and provides a method for manufacturing an ultra-thick corrosion-resistant container capable of manufacturing an inner layer made of a strength material and an outer layer made of a corrosion-resistant material without gaps. It is intended for.

[0012]

According to the present invention, a container is formed by forming a corrosion-resistant outer layer 15 on the outer surface of a thick-strength material portion 9 for forming an inner layer of a container body through an intermediate layer 13 at the stage of factory processing. In addition to forming the main body 5, the container lid 7 is formed by forming a corrosion-resistant outer layer 26 on the outer surface of the thick-walled strength material portion 23 for forming the inner layer of the container lid via an intermediate layer 25. Groove 8 formed between the container lid 7
A stepped discontinuous groove 34 in which the corrosion-resistant outer layers 15 and 26 are lowered by one step with respect to the intermediate layers 13 and 25 is formed, and the container body 5 and the container lid 7 are connected to each other at the stage of on-site processing. The groove 8 formed therebetween is weld-welded from the back side in the order of the strength material and the intermediate layer, and then the corrosion-resistant material is weld-welded on the stepped discontinuous groove 34. The present invention relates to a method for manufacturing a super-thick corrosion-resistant container.

In this case, the first layer backside welding 35 of the weld overlay of the strength material on the back side of the groove 8 may be performed by Tig welding using helium gas as a shielding gas.

According to the above means, the following effects can be obtained.

Since the stepped discontinuous groove 34 is formed in the corrosion-resistant material portion of the groove portion 8, the weld overlay of the strength material portion and the weld overlay of the intermediate layers 13 and 25 can be changed to the corrosion-resistant outer layer 15. , 2
6 so that the weld overlay of the strength material portion and the weld overlay of the intermediate layers 13 and 25 are applied to the corrosion-resistant outer layers 15 and 26, and the corrosion-resistant outer layer 1
It is possible to reliably prevent the occurrence of defects such as cracks or brittleness of 5, 26.

Also, by performing the first layer backside wave welding 35 by Tig welding using helium gas as a shielding gas,
It is possible to perform welding with deep penetration and to form a sound welding backwash.

As described above, the strength material and the corrosion-resistant material outer layer 15, 2
The integrated super-thick corrosion-resistant container 4 having no space between 6 can be easily and reliably manufactured by remote control.

[0018]

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

FIGS. 1 to 4 show an embodiment of the present invention.

In FIG. 1, reference numeral 4 denotes a super-thick corrosion-resistant container, 5 denotes a container main body of the super-thick corrosion-resistant container 4, 6 denotes a housing space of the container main body 5, 7
Is a drop lid type container lid of the ultra-thick corrosion-resistant container 4, and 8 is a groove formed between the container body 5 and the container lid 7.

In FIG. 2, reference numeral 9 denotes a thick strength member for forming the inner layer of the container body constituting the container body 5, 10 denotes an upper edge portion of the thick strength material portion 9 for forming the inner layer of the container body, and 11 denotes an upper edge portion 10. Step 12 for building up formed on the outer peripheral surface of the thick strength material portion 9 for forming the inner layer of the container body, 13 is an intermediate layer formed on the upper edge 10 of the thick strength material portion 9 for forming the inner layer of the container body, Reference numeral 14 denotes an intermediate layer formed on the outer peripheral surface 12 of the thick strength material portion 9 for forming the inner layer of the container body, reference numeral 15 denotes an outer layer of a corrosion-resistant material formed on the intermediate layer 13,
Is a corrosion resistant outer layer formed on the intermediate layer 14, 17 is a stepped groove formed between the intermediate layer 13 and the corrosion resistant outer layer 15, 18 is a handle attached to the corrosion resistant outer layer 15, 19 Is an inner diameter adjusting portion formed on the thick strength material portion 9 for forming the inner layer of the container body, 20 is a step portion for locking the lid formed on the inner diameter adjusting portion 19 of the thick strength material portion 9 for forming the inner layer of the container body, 21 is a lid. A groove forming portion formed on the locking step portion 20 is a groove forming portion formed on the intermediate layer 13 above the groove forming portion 21.

In FIG. 3, reference numeral 23 denotes a thick-walled strength member for forming the inner layer of the container lid constituting the container lid 7; Reference numeral 25 denotes an intermediate layer formed in the peripheral groove for overlay, 26 denotes a corrosion-resistant outer tank attached to the upper surface of a thick-strength material portion 23 for forming a layer inside the container lid by explosion or the like, and 27 denotes a thickness for forming a layer inside the container lid. Meat strength part 23
A container locking edge formed on the bottom surface of the container; 28, a groove-forming portion formed on the upper surface side of the thick-walled strength material portion 23 for forming a container lid inner layer; 29, an intermediate layer 25 on the groove-forming portion 28; A groove portion formed in the portion, 30 is a stepped groove portion formed between the intermediate layer 25 and the corrosion-resistant outer layer 26, and 31 is a backing metal attached to the container locking edge 27. .

In FIG. 4, reference numeral 32 denotes a narrow groove on the back side of the groove 8 formed between the container body 5 and the container lid 7, and 33 denotes a portion formed on the intermediate layers 13, 25 of the groove 8. The groove to be formed, 34 is a stepped groove formed in the corrosion-resistant material outer layers 15 and 26 of the groove 8, 35 is the first layer uranami welding to the narrow groove 32, 36 is the strength material of the narrow groove 32 Department.

In the present invention, at the stage of factory processing,
A container body 5 of the ultra-thick corrosion-resistant container 4 and a drop-down type container lid 7 of the ultra-thick corrosion-resistant container 4 are separately formed, and a dropping lid is formed on the container body 5 containing the vitrified body at the stage of on-site processing. The container lid 7 is attached in such a manner that the groove 8 between the container body 5 and the container lid 7 is welded.

First, the production of the container body 5 by factory processing is performed as follows.

That is, FIG.
As shown in FIG. 2A, a thick strength member 9 for forming an inner layer of a container body having a thickness as large as about 200 mm or more is formed, and an upper edge 10 of the thick strength member 9 for forming a container body inner layer is formed. FIG.
As shown in FIG. 2B, the outer peripheral side is cut and removed one step lower while leaving a part of the inner peripheral side of the upper end edge portion 10 to form the overlaying step portion 11. Next, FIG. As shown in FIG. 5, the welding is performed on both the strength member and the corrosion-resistant material to the step portion 11 for the build-up on the outer peripheral side of the upper edge 10 and the outer peripheral surface 12 of the thick-strength material portion 9 for forming the inner layer of the container body. The intermediate layers 13 and 14 are formed by building up an intermediate material having good properties, and as shown in FIG.
The surplus portions in the claddings 3 and 14 are ground to prepare the surface.

Then, as shown in FIG. 2E, a corrosion-resistant material such as titanium is laid on the intermediate layers 13 and 14 to form corrosion-resistant outer layers 15 and 16, and the thickness of the corrosion-resistant outer layers 15 and 16 is increased. The surface is prepared by grinding the surplus portion of the asperity. At this time, the corrosion-resistant outer layers 15 and 16 form the stepped discontinuous groove forming portion 17 so as to leave a part of the upper edge 10 on the inner peripheral side of the intermediate layer 13.

Next, as shown in FIG. 2 (f), a ring-shaped handle 18 is welded to the outer layers 15 and 16 of the corrosion-resistant material, and further, as shown in FIG. An inner diameter adjusting portion 19 is formed by processing the upper portion of the inner peripheral surface of the meat strength material portion 9 to adjust the inner diameter. Finally, as shown in FIG. Middle layer 1 in
Part of the inner peripheral side of 3, 14 is cut diagonally and stepwise,
In order from the bottom, a step portion 20 for lid locking, a groove forming portion 21,
The container body 22 is formed by forming 22.

Similarly, to make the container lid 7 by factory processing, the following is performed.

That is, the thickness 2 is made of a strength material such as carbon steel.
The thick-walled strength material portion 23 for forming a container lid inner layer having a thickness of about 00 mm or more is formed so as to be slightly larger than the completed container lid 7. As shown in FIG. 3A, a circumferential groove is formed on the upper surface at a position corresponding to the outer edge of the completed container lid 7 to form a built-up circumferential groove 24. Next, FIG. As shown in b), a material having good weldability with respect to both the strength material and the corrosion-resistant material is clad in the cladding peripheral groove portion 24 and the intermediate layer 2 is formed.
5 is formed, and as shown in FIG. 3 (c), the surplus portion of the overlay of the intermediate layer 25 is ground to prepare the surface.

Then, as shown in FIG. 3D, a corrosion-resistant material plate such as titanium is attached to the upper surface of the thick-strength material portion 23 for forming the inner layer of the container lid by explosion-bonding or the like to form the corrosion-resistant outer layer 26. create.

Next, as shown in FIG. 3 (e), the outer edge of the bottom surface of the thick strength member 23 for forming the inner layer of the container lid is subjected to cutting to form an edge 27 for locking the container. , FIG. 3 (f)
As shown in FIG. 3, the outer edge of the thick-walled strength material portion 23 for forming the inner layer of the container lid and the intermediate layer 25 are cut off diagonally, and
8 and 29 are formed, and the outer edge of the corrosion-resistant outer layer 26 is cut off so as to have a step with respect to the outer edge of the intermediate layer 25 to form a stepped discontinuous groove forming section 30. Finally, FIG. As shown in (g), the back cover 31 is attached to the container locking edge 27 on the bottom surface of the thick-walled strength material portion 23 for forming the inner layer of the container lid, and the container lid 7 is obtained.

Finally, to weld the container lid 7 to the container body 5 at the stage of on-site processing, the following is performed.

That is, the vitrified body is housed in the container body 5, and the container body 7 containing the vitrified body is attached with the container lid 7 in a dropping lid manner. Is to be welded.

The weld overlay between the container body 5 and the container lid 7 is made as follows.

That is, when the container lid 7 is inserted into the container main body 5 in a drop-down manner, as shown in FIG. 27 are locked, and the groove constituting portions 21 and 22 of the container body 5 and the container lid 7 are locked.
Between the narrow groove 32 and the groove 3
3 is formed, and a stepped discontinuous groove 34 is formed between the stepped discontinuous groove forming section 17 of the container body 5 and the stepped discontinuous groove forming section 30 of the container lid 7. Then, the first layer surf welding 35 to the narrow groove 32 is performed by Tig welding using helium gas as the shielding gas, and after the first layer surf welding 35, the remaining strength material portion 36 of the narrow groove 32 is used as the shielding gas. A welding wire made of a strength material by normal Tig welding or Mig welding using argon gas is weld-welded, and a narrow groove 3 is formed.
If the strength material portion 36 in 2 is weld-welded, the surplus is polished after welding if necessary.

Thereafter, the intermediate layers 13 and 2 in the groove 33 are formed.
The portion of No. 5 is clad by Tig welding using a welding wire made of an intermediate material, and if necessary, the surplus wall is polished after the cladding.

Lastly, the portions of the outer layers 15 and 26 of the corrosion-resistant material in the stepped discontinuous groove 34 are overlaid by Tig welding using a welding wire made of an anti-corrosion material, and the excess material is polished after welding. .

As described above, the container body 5 and the container lid 7 are securely welded in place.

As described above, by performing the first layer reverse welding 35 by Tig welding using helium gas as the shielding gas, a deep penetration welding can be performed and a sound welding reverse welding can be formed. .

The remaining portion of the strength material in the narrow groove 32 is replaced with a normal Tig using argon gas as a shielding gas.
By performing the weld overlay by welding or Mig welding, it becomes possible to perform the weld overlay with higher efficiency as compared with the case where the first layer reverse welding 35 is performed. In particular, if Mig welding is used, it is possible to perform welding overlaying with higher efficiency.

Furthermore, the stepped discontinuous groove 34 is formed in the corrosion-resistant material portion of the groove portion 8, so that the weld overlay of the strength material portion 36 and the weld overlay of the intermediate layers 13 and 25 can be reduced. It can be performed away from the food material outer layers 15 and 26, so that the weld overlay of the strength material portion 36 and the intermediate layers 13 and 26 can be formed.
The weld overlay of 25 parts is applied to the corrosion-resistant outer layers 15, 26,
It is possible to reliably prevent the occurrence of defects such as the corrosion-resistant outer layers 15 and 26 becoming cracked or brittle.

As described above, the strength material and the corrosion-resistant material outer layer 15, 2
The integrated super-thick corrosion-resistant container 4 having no space between 6 can be easily and reliably manufactured by remote control.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the spirit of the present invention.

[0045]

As described above, according to the method for manufacturing a super-thick corrosion-resistant container of the present invention, it is possible to manufacture an inner layer made of a strength material and an outer layer made of a corrosion-resistant material without any gap. This can provide an excellent effect.

[Brief description of the drawings]

FIG. 1 is a perspective view of a super-thick corrosion-resistant container according to an example of an embodiment of the present invention.

FIG. 2 is an enlarged view of a part II of FIG. 1 showing a process of manufacturing a container main body at a stage of factory processing, wherein (a) is a diagram showing a thick-strength material portion for forming an inner layer of the container main body; (b) is a diagram showing a state in which a build-up step is formed in the thick strength material portion for forming the inner layer of the container body, and (c) is a diagram showing a state in which the intermediate layer is build-up welded to the build-up step. (D) is a diagram showing a state in which the excess thickness of the intermediate layer is removed, (e) is a diagram showing a state in which the corrosion-resistant outer layer is overlaid on the intermediate material,
(F) is a figure which shows the state which attached the handle to the upper surface of the container body inner layer formation thick-strength material part, and (g) is the state which formed the inner diameter adjustment part in the container body inner layer formation thick-strength material part. It is a figure which shows the state which formed the groove | channel groove part in the thick-strength material part for container main body inner layer formation.

3A and 3B are diagrams illustrating a process of manufacturing a container lid at a stage of factory processing, and FIG. 3A illustrates a state in which a built-up peripheral groove portion is formed in a thick-strength material portion for forming a container lid inner layer. FIG.
(B) is a view showing a state in which the intermediate layer is overlaid and welded to the overlaying groove, (c) is a view showing a state in which the excess thickness of the intermediate layer has been removed, and (d) is a view showing the inside of the container lid. It is a figure which shows the state which carried out the explosion processing of the outer layer of the corrosion-resistant material on the upper surface of the thick-strength material part for layer formation, FIG. It is a figure which shows the state in which was formed, (f)
FIG. 4 is a view showing a state in which a groove forming part is formed on the upper surface side of the thick-strength material part for forming a container lid inner layer, and FIG. 4 (g) shows a state in which a backing metal is attached to a container locking edge. FIG.

FIG. 4 shows a state where a groove is welded at a stage of on-site processing;
FIG. 4 is an enlarged view of a part IV in FIG. 1.

FIG. 5 is a partially cutaway perspective view of an ultrathin corrosion-resistant container currently under study.

[Explanation of symbols]

 Reference Signs List 5 container body 7 container lid 8 groove portion 9 container body inner layer forming thick wall material 13, 25 intermediate layer 15, 26 corrosion resistant outer layer 23 container lid inner layer forming thick wall member 34 stepped discontinuous opening Previous 35 First layer Uranami welding

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G21F 9/36 541 G21F 9/36 541D (72) Inventor Junko Shinozuka 1 Shinnakaharacho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Ishikawajima-Harima Heavy Industries Yokohama Engineering Center Co., Ltd.

Claims (2)

[Claims] At the stage of factory processing, a corrosion-resistant outer layer (15) is formed on an outer surface of a thick-strength material portion (9) for forming an inner layer of a container body via an intermediate layer (13), thereby forming a container body (15). The container lid (7) is formed by forming a corrosion-resistant outer layer (26) on the outer surface of the thick-walled strength material portion (23) for forming the inner layer of the container lid through an intermediate layer (25). In the groove 8 formed between the container body 5 and the container lid 7, the corrosion-resistant outer layers 15 and 26 with respect to the intermediate layers 13 and 25 are formed. ) Is formed so as to form a stepped discontinuous groove (34), and a groove () formed between the container body (5) and the container lid (7) at the stage of on-site processing. 8) is weld-welded from the back side in the order of the strength material and the intermediate layer, and then a corrosion-resistant material is weld-welded on the stepped discontinuous groove (34). A method for producing a super-thick corrosion-resistant container, characterized by comprising: 2. The super weld according to claim 1, wherein the back layer welding (35) of the weld overlay of the strength material on the back side of the groove (8) is performed by Tig welding using helium gas as a shielding gas. Manufacturing method of thick corrosion resistant container.