JPH10104376A - Vacuum container for fusion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage of radiation shield by providing dross receivers on the outer wall of vacuum vessel outside a sector division lines along the division lines. SOLUTION: On a vacuum vessel 1 constituting by dividing in sector shapes in the torus direction, dross receivers 15 are provided by welding or bolting on the outer wall of the vacuum vessel periphery along sector division lines. For example, in the case the vacuum vessel 1 is cut and divided into sectors in the moment of failure of a nuclear fusion device, the vacuum vessel wall is cut by plasma from the inner wall of the vacuum vessel 1. The dross generated at the moment scatters to the back of the outer wall. As this is received and contained with the dross receivers 15, direct scattering to the radiation shield is prevented and so damage of the radiation shield is prevented so that the function is maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum vessel for a nuclear fusion device for confining plasma.

[0002]

2. Description of the Related Art FIG. 9 schematically shows a longitudinal section of a conventional donut-type fusion device only at a right portion from a center line, and FIG. 10 is a horizontal sectional view of a main part in FIG. That is, in FIGS. 9 and 10, the nuclear fusion device includes a donut-shaped plasma vacuum vessel 1, a superconducting toroidal coil 2, a radiation shield for shielding radiant heat to the toroidal coil 2, a poloidal coil 4 for controlling plasma (not shown), and the like. Be composed.

FIG. 11 shows a connecting portion between sectors of the vacuum vessel 1 in FIG. 9. The vacuum vessel wall 5 constituting the vacuum vessel 1 has a double wall structure comprising an inner wall 6, an outer wall 7 and a rib 8. The connection between sectors is made by using a splicer 9 on the inner wall 6 side. If a failure occurs in the toroidal coil 2 or the vacuum vessel 1 during operation of the device,
It is necessary to stop the operation of the device and disassemble and repair the faulty part.

FIG. 12 is an exploded partial view of the vacuum vessel 1, and the vacuum vessel 1 is arranged so as to interlink with a toroidal coil 2. In the vacuum vessel 1, a wedge sector 10 cut into a sector shape in the toroidal direction is pulled out from between the toroidal coils 2 and disassembled. Sector cutting is performed from the inside of the vacuum vessel 1, and first, the splicer 9 on the inner wall 6 side shown in FIG. 11 is cut, and then the outer wall 7 side is cut.

[0005] Various methods are conceivable for cutting the container wall 5, but since the vacuum container 1 is made of metal such as stainless steel, plasma cutting using a plasma arc and laser cutting using a laser beam are performed. Cutting or the like is used. These operations are performed from the inside of the vacuum vessel 1 because the space between the vacuum vessel 1 and the toroidal coil 2 is narrow.

[0006] When cutting a metal plate by plasma cutting or laser cutting, the plasma cutting is performed by a plasma jet, and the laser cutting is performed by blowing a molten portion behind a metal plate by an assist gas. Therefore, the melted portion blown off in the cutting of the vacuum vessel 1 hits the radiation shield 3 as dross, a part of which adheres, and the others fall and accumulate in the lower space.

[0007] In addition, these welds need to be subjected to a nondestructive inspection at the end of welding in order to ensure quality, a surface inspection is performed by a liquid penetration test (PT), a volume inspection is a radiation transmission test (RT), an ultrasonic flaw detection. The test (UT) was performed, but there was no means for performing a liquid penetration test outside the welded portion of the outer wall 7 of the vacuum vessel.

The radiation shield 3 includes a vacuum vessel 1 and a superconducting toroidal coil 2 for reducing radiant heat to the superconducting coil.
The temperature is set at an intermediate temperature between the two, and is generally used at around 77K. To maintain this temperature, as shown in FIG.
And a multi-layered heat insulating material 13 in which a film surface such as a mylar is deposited with aluminum. The radiation shield 3 is installed in units of vacuum vessel sectors, and the sectors are superimposed so that the low temperature side cannot be directly optically viewed from the normal temperature side.

[0009]

However, if the radiation shield 3 is exposed to sparks or dross due to cutting, the multilayer heat insulating material 13 will burn out, and the radiation shield 3 will not function. In addition, the liquid permeation test outside the welded portion of the vacuum vessel outer wall 7 cannot be performed because the test device cannot access the liquid permeation test. Further, the radiation shield 3 has another problem that if the sectors are simply overlapped, the vacuum vessel 1 cannot be disassembled or pulled out.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and in the event of a failure of a vacuum vessel or a toroidal coil, damage to other equipment due to cutting between sectors is prevented, and the disassembly and withdrawal of a sector is ensured. An object of the present invention is to provide a vacuum vessel for a fusion device that can be used.

[0011]

According to a first aspect of the present invention, there is provided a vacuum vessel for a nuclear fusion device, comprising: a plasma confining device which is divided into multiple sectors in a torus direction in a sector shape; A dross receiver is provided on the outer wall of the vacuum vessel along the dividing line.

According to the present invention, since the dross receiver is provided on the outer wall 7 of the vacuum vessel 1 along the sector cutting line of the vacuum vessel 1, the dross accompanying the cutting does not directly hit the radiation shield. In addition, the radiation shield can be prevented from being damaged.

According to a second aspect of the present invention, there is provided a vacuum vessel for a fusion apparatus comprising a wedge-shaped sector disposed between toroidal coils and a parallel-shaped sector disposed at the same angle as the toroidal coil. With the radius position at the maximum dimension as a boundary, a dross receiver is provided on the parallel sector side for the area inside this boundary,
In a region outside the boundary, a dross receiver is provided on the wedge-shaped sector side.

According to the present invention, the dross tray 14 is
Based on the maximum dimension position in the vertical direction, the dross receiving position is changed at this position. That is,
For the sector that is installed between the toroidal coils and pulled out first, a dross receiver is installed on the sector side to be pulled out for the outboard side based on the radial position that is the maximum vertical dimension of the vacuum vessel, and for the inboard side Installed in the other sector.

According to a third aspect of the present invention, the cross section of the dross receiver is L-shaped or U-shaped or the like, and one end of a mounting portion to the outer wall of the vacuum vessel is sealed and connected to one end. It is characterized by providing a certain sealing member.

According to the present invention, the dross receiver is formed in a U-shape on the outer wall, and an elastic seal portion is provided at the tip of the dross receiver. It constitutes the boundary of the shielding gas and the boundary of the detected gas in the leak test of the welded portion.

The invention corresponding to claim 4 is characterized in that a tooth-shaped rack is provided in a part of the dross receiver.
ADVANTAGE OF THE INVENTION According to this invention, it can be set as the driving | running | working rail for making a non-destructive inspection apparatus run in a poloidal direction by a dross receiver.

According to a fifth aspect of the present invention, a radiation shield plate is superimposed on the outside of a torus-shaped vacuum vessel for confining plasma which is divided into multiple sectors in the torus direction and outside the sector division line. In a vacuum vessel for a fusion device, the radiation position of the radiation shield plate of the wedge-shaped sector in a region inside the boundary is defined as a radius of the vacuum vessel which is the maximum dimension in the vertical direction. It is installed inside the mounting position of the radiation shield plate of the parallel sector in the inner region, the mounting position of the radiation shield plate of the wedge-shaped sector in the region outside the boundary, the parallel sector in the region outside the boundary. It is installed outside the radiation shield attachment position.

According to the present invention, the radiation shield has a boundary at a radial position at which the maximum dimension in the vertical direction of the vacuum vessel is set as a boundary, and in a region inside the boundary, a mounting position of the radiation shield plate is set. The radiation shield plate is installed outside the overlapped part for the parallel sector, while the radiation shield plate is installed outside the overlapped part for the wedge-shaped sector in the area outside the boundary. ,
By arranging the parallel sector inside the overlapping portion, it is possible to prevent the radiation shield from being damaged or interfered with by the cutting between the sectors, and it is possible to reliably disassemble and extract the sector.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a vacuum vessel for a nuclear fusion device according to the present invention will be described with reference to FIGS. 1 and 2, the same portions as those in FIGS. 9 to 13 are denoted by the same reference numerals, and the description of the overlapping portions will be omitted. FIG. 1 is a cross-sectional view schematically showing a main part for describing the present embodiment, and FIG. 2 is a longitudinal cross-sectional view showing a state in which a dross receiver 15 is attached to the outer wall 7 of the vacuum vessel 1 in FIG. is there.

In this embodiment, as shown in FIGS. 1 and 2, in a vacuum vessel 1 which is divided into multiple sectors in the torus direction, a vacuum is applied along a sector dividing line 21 on the outer periphery of the vacuum vessel 1. The dross receiver 15 is provided on the outer wall 7 of the container wall 5. The dross tray 15 is connected to the outer wall 7 of the vacuum vessel wall 5.
The method of mounting on the rim is performed by welding or bolts.

Next, the function and effect of the first embodiment will be described. For example, when the vacuum vessel 1 is cut and disassembled into a sector when the fusion device fails, the vacuum vessel wall 5 is cut from the inside of the vacuum vessel 1 by plasma cutting. At that time, the dross generated scatters behind the outer wall 7. I do. However, this dross is stored by colliding with the dross receiver 15 installed behind the cutting line, and can be prevented from scattering directly to the radiation shield 3. Therefore, there is no damage due to the scattering of the dross to the radiation shield 3, and the radiation shield 3
Function can be maintained.

Next, a second embodiment of the vacuum container according to the present invention will be described with reference to FIGS. FIG. 3 schematically shows a nuclear fusion device for explaining the present embodiment in a longitudinal section, and corresponds to FIG. FIG. 4 is a horizontal sectional view of the inboard side viewed from the AA plane in FIG. 3, and FIG.
FIG. 12 is a horizontal cross-sectional view of the outboard side as viewed from the -B plane. In each figure, the same parts as those in FIGS.

3 to 5, a dross receiver 15 arranged along the outer periphery of the vacuum vessel 1 is provided with a support portion provided on the wedge-shaped sector 10 on the outboard side from the boundary line 17 as shown in FIG. On the inboard side from the boundary line 17, a support is provided and attached to the parallel sector 15 as shown in FIG.

According to the present embodiment, the disassembly and withdrawal of the vacuum vessel 1 cuts between the sectors, and
Is moved horizontally and then pulled out. Looking at the interference relationship between the dross receiver 15 and the wedge-shaped sector 10 and the parallel-shaped sector 16 in this case, the dross receiver 15 installed in the wedge-shaped sector 10 on the outboard side is in a direction away from the parallel-shaped sector 16. No interference occurs, and the wedge-shaped sector 10 is positioned against the dross receiver 15 installed in the parallel-shaped sector 16 on the inboard side shown in FIG.
Is also away, so there is no interference. Therefore, the wedge-shaped sector 10 can reliably perform necessary disassembly and pull-out.

Next, a third embodiment of the vacuum vessel according to the present invention will be described with reference to FIG. FIG. 6 shows a longitudinal section of only a main part of the present embodiment. In the present embodiment, the dross receiver 15 is attached to the surface of the outer wall 7 opposite to the groove of the welding portion 19, and the seal portion 18 is provided at one opening of the dross receiver 15.

According to the present embodiment, the dross receiver 15 is attached to one (one side) of the sectors connecting the sectors by welding or bolts, but the thin metal sheet is attached to the non-attached portion corresponding to the other (opposite) sector. An elastic seal portion 18 made of synthetic resin or the like is provided to form a flow path and a boundary of the shield gas for welding when the vacuum vessel sector is rewelded. As a result, a highly reliable weld can be obtained,
In addition, the boundary of the detected gas is formed in the leak test after welding, and the leak test can be reliably performed.

Next, a fourth embodiment of the vacuum vessel according to the present invention will be described with reference to FIG. FIG. 7A shows only a main part of this embodiment in a longitudinal section, and FIG. 7B shows FIG.
5 is a CC cross section of FIG. In the present embodiment, the rack 20 is formed on the outer surface of the dross receiver 15 attached to the outer wall 7.
This dross receiver 15 is also used as a traveling rail of the nondestructive inspection device in the poloidal direction.

According to the present embodiment, the non-destructive inspection device can be installed by the rack 18 provided on the dross tray 15,
And the traveling can be performed reliably. Therefore, it is possible to easily perform the nondestructive inspection of the surface of the welded portion even in a place where the worker is difficult to approach.

Next, a fifth embodiment of the vacuum vessel according to the present invention will be described with reference to FIG. FIG. 8 corresponds to FIG. 12, in which FIG. 8A shows the inside of the vacuum vessel, and FIG.
The outside on the radial extension line of (a) is shown. In this embodiment, in FIGS. 8A and 8B, the radiation shield 3 is installed at intervals on the entire inner surface and the outer surface of the vacuum vessel 1, but the sector dividing portion is the same as the dross receiver 15. As described above, the support portion is provided on the wedge sector 10 on the outboard side from the boundary line 17 shown in FIG. 3, and the support portion is provided on the parallel sector 16 on the inboard side from the boundary line 17.

On the inboard side inside the boundary 17, the radiation shield 3 of the wedge-shaped sector 10 is located inside the radiation shield 3 of the parallel-shaped sector 16 (on the side of the vacuum vessel 1).
On the outboard side outside the boundary line 17, the radiation shield 3 of the parallel sector 16 is connected to the wedge-shaped sector.
It is installed inside the radiation shield 3 (vacuum vessel 1 side).

According to the present embodiment, wedge sector 10
In addition, the cutting, disassembly, and pull-out of the parallel sector 16 can be reliably performed without interference with the radiation shield 3.
In addition, by superimposing the radiation shield 3 of the disassembly portion, it is possible to surely reduce the heat entering directly from the normal temperature portion into the superconducting coil due to radiation.

[0033]

According to the present invention, dross receiving at the time of cutting a sector can be performed without interfering with disassembling and pulling out the sector of the vacuum container. Then, a non-destructive inspection of the connection portion can be performed, and a highly reliable connection portion can be obtained. In addition, the radiation shield can also perform sector disassembly and extraction without interference.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a main part of a vacuum vessel for a fusion device according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an attached state of the dross receiver in FIG. 1;

FIG. 3 is a longitudinal sectional view schematically showing a nuclear fusion device for explaining a second embodiment of the nuclear fusion device vacuum vessel according to the present invention.

FIG. 4 is a horizontal sectional view taken along the line AA in FIG. 3;

FIG. 5 is a horizontal sectional view taken along a line BB in FIG. 3;

FIG. 6 is a longitudinal sectional view schematically showing a main part of a third embodiment of the vacuum vessel for a fusion device according to the present invention.

FIG. 7A is a longitudinal sectional view showing a main part of a fourth embodiment of a vacuum vessel for a nuclear fusion device according to the present invention, and FIG. 7B is a sectional view taken along the line CC in FIG.

8A is a plan view showing the inside of a fifth embodiment of the vacuum vessel for a nuclear fusion device according to the present invention, and FIG.
FIG.

FIG. 9 is a longitudinal sectional view schematically showing a tokamak fusion device.

FIG. 10 is a plan view showing a main part in FIG. 9;

11 is a longitudinal sectional view partially showing a sector connection portion of the vacuum vessel in FIG. 10;

FIG. 12 is a plan view schematically showing a state where the vacuum vessel sector is disassembled and pulled out in FIG. 10;

FIG. 13 is a partial sectional view of a radiation shield in FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Plasma vacuum container, 2 ... Toroidal coil, 3 ... Radiation shield, 4 ... Poloidal coil, 5 ... Vacuum container wall,
6 inner wall, 7 outer wall, 8 rib, 9 splicer, 10
... Wedge sector, 12 ... Cooling plate, 13 ... Multilayer insulation, 14 ...
Cooling channel pipe, 15… Dross receiver, 16… Parallel sector, 17…
Boundary line, 18… Seal, 19… Weld, 20… Rack, 21…
Split line.

Claims (5)

[Claims] In a vacuum vessel for a nuclear fusion device, wherein plasma is confined and divided into multiple sectors in a torus direction, a dross receiver is provided along the division line outside the multiple division line. A vacuum vessel for a nuclear fusion device. 2. A vacuum vessel for a fusion device comprising a wedge-shaped sector disposed between toroidal coils and a parallel-shaped sector disposed at the same angle as the toroidal coil. A dross receiver is provided on the parallel sector side for an area inside the boundary, and a dross receiver is provided on the wedge-shaped sector side for the area outside the boundary. 3. The dross receiver has an L-shape or U-shape in cross section, and one end of a mounting portion to the outer wall of the vacuum vessel is sealed and connected, and one end is provided with an elastic sealing member. 3. The vacuum vessel for a nuclear fusion device according to claim 1, wherein: 4. The vacuum vessel for a fusion device according to claim 1, wherein a tooth-shaped rack is provided in a part of the dross receiver. 5. A nuclear fusion device comprising a radiation shield plate superposed and installed outside of a sector dividing line outside a torus-shaped vacuum vessel for confining plasma, which is divided into multiple sectors in the torus direction. In the device vacuum vessel, the radial position of the maximum dimension in the vertical direction of the vacuum vessel as a boundary, the mounting position of the radiation shield plate of the wedge-shaped sector in the area inside this boundary, the parallel sector of the area inside the boundary from the boundary. It is installed inside the mounting position of the radiation shield plate, the mounting position of the radiation shield plate of the wedge-shaped sector in the area outside the boundary, is installed outside the radiation shield mounting position of the parallel sector. Characteristic vacuum vessel for fusion devices.