JPH07167972A - First wall of fusion device - Google Patents

Abstract

PURPOSE:To provide a first wall for a nuclear fusion device excellent in mechanical strength and high in reliability. CONSTITUTION:In the first wall of a nuclear fusion device of such structure that an armor tile 21 is fixed to an armor supporting seat 24, provided on a cooling base board 22, by an armor fitting bolt 25, the head back face and thread part inner diameter of the armor fitting bolt 25 are provided with solder embedding grooves with preplaced solder 27 embedded therein, and the armor fitting bolt 25 is heated at the bolt fastening time to melt the preplaced solder 27, thus bonding the armor tile 21, the bolt head and bolt thread part, and the armor supporting seat 24 to one another.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a first wall such as a diverter or limiter of a nuclear fusion device.

[0002]

2. Description of the Related Art In a nuclear fusion device, as shown in FIG. 7, a vacuum container 2, a blanket or a shield, which forms a vacuum boundary against a high heat load and a high particle load from a high temperature and high energy plasma 1, is provided. A first wall 3 is provided on the plasma side surface of these members for protection purposes.

When the metal wall directly faces the plasma 1, neutral particles or the like during charge exchange enter the metal wall,
Due to a phenomenon such as sputtering, metal particles having a high atomic number are mixed into the plasma 1 as impurities, which hinders the plasma operation. Therefore, the first wall is generally made of a high melting point, low atomic number material such as graphite or ceramic material.

Further, the heat-resistant tile (hereinafter referred to as an armor tile) on the surface of the first wall 3 has a high heat load and a high particle load due to the radiation from the plasma 1 and the incidence of ions, electrons, neutral particles and the like. Must be replaced due to damage or wear. Considering activation in the furnace by plasma operation, it is desirable that the first wall 3 has a mechanical connection structure that can be exchanged by remote control.

FIG. 8 is a sectional view showing a typical first conventional wall. In FIG. 8, the armor tile 4 is fixed to an armor support seat 6 provided on a cooling substrate 5 made of non-magnetic steel via an armor mounting bolt 7. The armor support seat 6 is generally fixed to the cooling substrate 5 by welding. In addition, the cooling substrate 5
Is provided with a cooling flow path 8 for cooling water for removing heat from the incident heat load from the plasma.

Since the armor tile 4 and the armor mounting bolt 7 are members facing the plasma, they are made of a high melting point, low atomic number material such as graphite or ceramic material.
As shown in FIG. 7, it is arranged on the entire peripheral surface of the plasma 1.

On the other hand, since the first wall receives a high heat load from the plasma, an armor made of a high melting point material such as graphite, tungsten, molybdenum and a copper having a coolant passage for removing heat from the plasma are formed. Alternatively, there is a heat sink made of a highly heat conductive material such as a copper alloy.

FIG. 9 is a sectional view showing such a first wall. The first wall shown in FIG. 9 has a configuration in which a graphite or carbon fiber composite material (CFC) armor 11 and a copper heat sink 12 containing a copper cooling tube 13 are metallurgically joined together,
The joint surface 14 of both members forms a flat surface, and the joint surface end 15 is a free boundary surface. Further, the inside of the cooling pipe 13 is configured to receive the cooling water internal pressure 16 that has been passed for removing heat.

Generally, the high melting point material forming the armor member has a small coefficient of thermal expansion, and the difference in the coefficient of thermal expansion between the copper heat sink material for joining the armor material is large. Therefore, in the metallurgical joining structure, excessive thermal stress is generated near the joining interface during joining or during plasma heat load. FIG. 10 is an enlarged view of the end portion of the joint surface of FIG. 9, in which the thermal stress is 15
It becomes the maximum, and cracks 17 tend to occur at the end of the joint surface.

FIG. 11 is a cross-sectional shape of the first wall of the joining type which is conceived to solve the above-mentioned problems.
A circular hole is provided in the center of the FC armor 11, and a copper cooling pipe 13 is inserted to perform metallurgical joining. In FIG. 11, since the joint interface 14 is closed, the joint end portion does not exist structurally, and excessive thermal stress is suppressed from being generated on the joint interface during joining or under load. Here, the joining structure of FIG. 9 is referred to as a “flat type joining structure”, and the joining structure of FIG. 11 is referred to as a “monoblock type joining structure”.

[0011]

However, the following problems can be considered in the first wall of the heat receiving plate structure as shown in FIG. When heat is applied to the armor tile 4 and the armor mounting bolt 7 due to nuclear heat generated by high heat load or neutron load from plasma, this heat is applied to the contact portion between the support seat 6 on the cooling substrate 5 and the armor tile 4 and the armor mounting bolt 7. It is a mechanism that conducts heat to the cooling substrate 5 from the contact portion with the screw portion, and cools and removes heat by the cooling water flowing in the cooling flow path 8 provided in the cooling substrate 5.

Therefore, in such a heat removal mechanism,
It has sufficient cooling performance when the contact heat conduction between the above members is good or when the heat load is small, but when the contact surface failure of the contact surface or the heat load is large, the armor tile and the armor mounting bolt There was a danger that the temperature would increase significantly and that it would be a problem from the viewpoint of heat removal.

In particular, there has been a problem that the high temperature of the armor mounting bolt makes it impossible to disassemble and repair the armor tile when the armor tile is damaged due to galling or welding of the screw portion, which seriously hinders the operation of the fusion device.

Further, in the first wall of the monoblock type joint structure as shown in FIG. 11, the following problems can be considered. The divertor plate for the large-scale fusion experimental reactor class and the cooling water internal pressure 16 of the first wall, which is planned for the future, are approximately 3.5 MPa.
And big. For this reason, the stress due to the internal pressure 16 of the cooling water in the cooling pipe 13 increases, and the joint structure may be damaged due to the plastic deformation of the copper cooling pipe 13.

Further, since the cooling pipe copper is softened by the high temperature at the time of joining, the mechanical strength of the copper cooling pipe is lowered. This has the same problem in the first wall of the flat joint structure of FIG.

Therefore, it is conceivable to use dispersion strengthened copper such as alumina and zirconia having high temperature and high strength characteristics in the cooling pipe without lowering the thermal conductivity. In FIG. 12, the dispersion strengthened copper cooling pipe 13a is applied to the first wall of the monoblock type joint structure.

However, if the strength of the cooling pipe 13a is high, the graphite or CFC armor 11 is formed at the bonding interface 14.
The reaction force against is large and graphite or CFC armor 11
It also causes a crack 17 to the side. This is because, on the contrary, the strength of the cooling pipe is high, plastic deformation does not occur at the time of joining, and an excessive reaction force is applied to the graphite or CFC armor 11 side.

Therefore, in the first wall of the monoblock type joint structure, although the problem of the end portion of the joint surface and the countermeasure against the high cooling water internal pressure 16 can be solved, the joint interface 14 in the vicinity of the joint material shoulder portion 18 at the time of joining is solved. A new problem of the crack 17 generated on the graphite or CFC armor 11 side occurs.

A first object of the present invention is to improve the thermal conductivity between the armor tiles, the armor mounting bolts and the cooling board, improve the efficiency of removing heat from the cooling board, and prevent the armature tiles and the armor mounting bolts from becoming hot. It is to provide the first wall of a fusion device with high reliability and reliability.

A second object of the present invention is to improve the reliability of the structural strength such that the armor will not be damaged when the graphite armor and the cooling pipe inserted in the center of the graphite armor are joined. It is to provide the first wall of a possible fusion device.

[0021]

In order to achieve the above object, the present invention constitutes the first wall of a nuclear fusion device by the following means. (1) In the first wall of the nuclear fusion device having a structure in which the armor tile is fixed to the armor support seat provided on the cooling board with the armor mounting bolt, the solder is embedded on the back surface of the head of the armor mounting bolt and the inner diameter of the screw part. When the bolts are fastened, the armor mounting bolts are heated to melt the placement solder, thereby bonding the armature tiles to the bolt heads, the bolt screw portions, and the armor support seats. (2) Further, a through hole for removing residual gas in the vicinity of the member contact surface is provided in the axial direction at the central portion of the armor mounting bolt having the above-mentioned configuration. (3) First of the nuclear fusion device having a structure in which a cooling pipe made of high temperature and high strength dispersion strengthened copper is inserted into a hole provided in the center of a graphite or carbon fiber composite material (CFC) armor, and both are metallurgically bonded. In the wall, said graphite or CF
A softened copper buffer material having a thermal deformation space is provided between the C armor and the cooling pipe and metallurgically bonded.

[0022]

In the first wall of the nuclear fusion device configured as described above in (1), when the bolt head is heated after the bolt of the armature is fastened, the inside of the groove provided in the bolt head rear surface and the screw inner diameter portion Placed solder melts and flows on the back surface of the bolt and the contact surface of the screw spiral, and the contact surface between the back surface of the bolt head and the armature and the contact surface between the bolt screw portion and the screw hole of the armor support seat are bonded. Therefore, the heat that the armature tile and the armor mounting bolt receive from the plasma is conducted to the cooling substrate through the adhesive surface and is removed by the cooling water in the cooling substrate.

Further, as described in the above (2), in order to improve the flow of the placed solder in the solder embedding groove at the time of fastening the bolt, a through hole is formed in the center of the bolt so as to be axially pulled out. The contact surface can be easily degassed, and the flow on the contact surface of the solder can be promoted.

In the first wall of the nuclear fusion device having the structure as described in (3) above, a cooling pipe made of dispersion strengthened copper is arranged in a hole provided at the center of graphite or CFC armor, and high internal pressure of cooling water is provided. Resistant to structure, graphite or CF
Since a softened copper buffer material having a thermal deformation space is provided between the C armor and the cooling pipe, it can withstand high cooling internal pressure under load and does not receive excessive thermal stress on the bonding interface, and graphite or CFC The armor will not be damaged, and reliable mechanical strength can be obtained.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a first embodiment of the first wall of the nuclear fusion device according to the present invention. In FIG. 1, reference numeral 21 denotes an armor tile having a bolt insertion hole 21a into which a bolt head and a screw portion can be inserted, and 22 denotes an armor support seat 24 having a cooling hole 23 formed therein and having a screw hole projected from a plate surface. This is the cooling substrate provided. Further, reference numeral 25 is an armor mounting bolt for fixing the armor tile 21 to the armor support seat 24 of the cooling board 22, and a through hole 26 is formed at the center of the armor mounting bolt 25 so as to be axially removed.

The armor tile 2 is attached to such a cooling substrate 22.
As shown in detail in FIG. 2, the head back surface and the screw inner diameter portion of the armor mounting bolt 25, and the solder embedding groove 28 in which the mounting solder 27 is embedded are further provided on the tile mounting surface of the armor support seat 24. The armature mounting bolt 25 is provided and inserted into the screw hole of the armor support seat 24 through the bolt insertion hole 21a of the armature tile 21 and tightened.

In this case, when the bolts are fastened, the armor mounting bolts 25 are heated to melt the placement solder 27, and the solder is poured into the solder bonding surface 29 between the members so that the armor tile 21
The bolt head portion, the bolt screw portion, the screw hole portion of the armor support seat 24, and the respective members on the mounting surface of the armature tile 21 and the armor support seat 24 are bonded together.

Further, at this time, the residual gas in the vicinity of the member contact surface is degassed from the through hole 26 provided at the center of the armor mounting bolt 25, so that the flow of the placing solder 27 to the member contact surface becomes good.

As described above, in the first embodiment,
A solder embedding groove 28 in which a mounting solder 27 is embedded is provided in the head rear surface of the armor mounting bolt 25, the screw inner diameter portion, and the tile mounting surface of the armor support seat 24, and the armor tile 21 is mounted on the armor support seat 24 of the cooling board 22. When the armor mounting bolt 25 is tightened and fixed to the armor mounting bolt 25, the armor mounting bolt 25 is heated and a solder is poured between the contact surfaces of the respective members so that the armor tile 21 and the bolt head portion, the bolt screw portion and the screw hole portion of the armor support seat 24, and The armature tile 21 and the armor support seat 24 are attached to each other at their mounting surfaces.

Therefore, the thermal contact and adhesion between the members are strengthened, and the heat conduction characteristics of the armor tile 21, the armor mounting bolt 25 and the cooling substrate 22 can be enhanced,
Armature tile 21 and armor mounting bolt 25 from plasma
Even if the heat is applied, the heat moves to the cooling board 22 through the solder bonding surface by the heat conduction mechanism and is removed by the cooling water flowing in the cooling flow path 23 in the cooling board 22. The heat removal efficiency of can be improved. As a result, it is possible to prevent the temperature of the first wall member from rising and to improve safety and reliability.

When the armature is disassembled, the bolt head is heated to melt the solder layer on the adhesive surface,
The armor tile 21 and the armor mounting bolt 25 can be easily removed.

Further, when the bolt is fastened, the solder burying groove 28
Since the through hole 26 is provided in the center of the bolt in order to improve the flow of the placed solder 27 inside, the armor support seat 2
4. It is possible to facilitate the degassing of the screw contact surface of the bolt and promote the flow on the contact surface of the solder.

Next, a second embodiment of the first wall of each fusion device according to the present invention will be described with reference to FIGS. 3 and 4. Figure 3
In, 31 is a graphite or CFC armor having a circular hole 32 in the center thereof.
Cooling pipe 3 made of dispersion strengthened copper in hole 32 of C armor 31
3 and insert graphite or CFC armor 3
1 and the cooling pipe 33, a plurality of softened copper buffers 34 divided in the circumferential direction are arranged with slits 35 between each, and graphite or CFC armor 31, dispersion strengthened copper cooling pipe 33 and The softened copper buffer material 34 is metallurgically bonded.

FIG. 4 is an enlarged view of the shoulder portion 36 of the joined body of FIG. 3, in which the metallurgical joining interface 37 is made of graphite or CF.
It occurs between the C armor 31 and the softened copper buffer material 34 and between the softened copper buffer material 34 and the dispersion strengthened copper cooling pipe 33.

In the case of the first wall of the nuclear fusion device having such a structure, since the dispersion strengthened copper cooling pipe 33 is arranged in the hole 32 of the graphite or CFC armor 31, the cooling pipe is softened at the time of joining. However, the structure can withstand the internal pressure of the high cooling water.

Also, graphite or CFC armor 31
And the dispersion-strengthened copper cooling pipe 33 are divided into a plurality of pieces in the circumferential direction, and the softening copper buffer material 34 is arranged so that the slits 35 exist between the divided portions. Graphite or CFC accompanying thermal stress due to thermal expansion difference between dispersion strengthened copper cooling tubes 33
The reaction force to the armor 31 side can be reduced by promoting the plastic deformation of the copper cushioning material.

At this time, the presence of the slits between the softened copper buffer materials divided in the circumferential direction promotes the plastic deformation of the buffer material without restraining it, and the graphite or CF near the bonding interface on the graphite or CFC armor 31 side.
The reaction force to the C armor 31 side can be reduced, an excessive reaction force is not applied to the armor material, and the armor is not damaged.

As described above, in the second embodiment,
A cooling pipe 33 made of dispersion-strengthened copper is arranged in a circular hole 32 provided at the center of the graphite or CFC armor 31 so as to withstand a high internal pressure of cooling water.
Between the FC armor 31 and the cooling pipe 33, the softened copper buffer material 34 divided into a plurality in the circumferential direction is provided with the slits 35 between each other, so that it can withstand a high cooling internal pressure at the time of loading, In addition, the graphite or CFC armor 31 can be formed as a highly reliable first wall with high strength without applying excessive thermal stress to the bonding interface and causing no damage.

Although the softened copper buffer material 34 is provided with the slits 35 between each other in the above embodiment, the softened copper buffer material 3 is provided as in the third embodiment shown in FIG.
A plurality of grooves 38 are provided in the radial direction along the circumferential direction of 4 to alleviate the armor thermal stress acting on the joint surface, particularly the joint surface between the graphite or CFC armor 31 and the softened copper buffer material 34. it can.

Further, as in the fourth embodiment shown in FIG. 6, as the softened copper buffer material region, the copper wire mesh copper mesh 3 made of copper is used.
Armature thermal stress can be relieved by making thermal deformation easy by making it 9 and ensuring a thermal deformation space.

[0041]

As described above, according to the present invention, it is possible to provide the first wall of the nuclear fusion device having excellent mechanical strength and high reliability.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the first wall of the nuclear fusion device according to the present invention.

FIG. 2 is a cross-sectional view showing in detail a connection structure between an armor mounting bolt and an armor support seat in the same embodiment.

FIG. 3 is a sectional view showing a second embodiment of the first wall of the nuclear fusion device according to the present invention.

FIG. 4 is an enlarged sectional view showing a shoulder portion of the joined body in the embodiment.

FIG. 5 is an enlarged sectional view showing a shoulder portion of a joined body according to a third embodiment of the present invention.

FIG. 6 is an enlarged sectional view showing a shoulder portion of a joined body according to a fourth embodiment of the present invention.

FIG. 7 is a schematic diagram of the reactor body around the first wall in the torus fusion device.

FIG. 8 is a sectional view showing a first wall of a conventional mechanical fastening structure.

FIG. 9 is a cross-sectional view showing a first wall of a conventional flat type joint structure.

FIG. 10 is an enlarged cross-sectional view showing an end portion of the joint surface of the first wall.

FIG. 11 is a cross-sectional view showing a first wall of a conventional monoblock type joint structure.

FIG. 12 is an enlarged cross-sectional view showing a joint surface end portion of the first wall.

[Explanation of symbols]

21 ... Armor tile, 21a ... Insertion hole, 22 ... Cooling board, 23 ... Cooling channel, 24 ... Armor support seat, 25 ... Armor mounting bolt, 26 ... Through hole, 27 ... Placed solder, 28 ...
Solder embedding groove, 29 ... Adhesive surface, 31 ... Graphite or CFC armor, 32 ... Circular hole, 33 ... Cooling tube made of dispersion strengthened copper, 34 ... Softened copper buffer material, 35 ... Slit, 3
6 ... groove.

Claims (7)

[Claims] 1. In a first wall of a nuclear fusion device having a structure in which an armor tile is fixed to an armor support seat provided on a cooling board by an armor mounting bolt, a solder is placed on a back surface of the head of the armor mounting bolt and an inner diameter of a screw part. By providing a groove in which the armor mounting bolt is melted by heating the armor mounting bolt when fastening the bolt, the armor tile and the bolt head and the bolt screw portion and the armor support seat are bonded together. The first wall of the characteristic fusion device. 2. The first wall of the nuclear fusion device according to claim 1, wherein a through hole for removing residual gas in the vicinity of the member contact surface is provided in the central portion of the armor mounting bolt in the axial direction. 3. The first wall of the nuclear fusion device according to claim 1, wherein the mounting surface of the armor support seat, which comes into contact with the back surface of the armor tile, is provided with a groove having embedded solder. 4. A graphite or carbon fiber composite material (C
(FC) A cooling tube made of dispersion-strengthened copper having high temperature and high strength is inserted into a hole in the center of the armor, and the graphite or CFC armor is cooled in the first wall of the fusion device having a structure in which both are metallurgically joined. A first wall of a nuclear fusion device, characterized in that a softened copper buffer material having a thermal deformation space is provided between the pipe and the metallurgical joint. 5. A soft copper buffer material is divided into a plurality of pieces in the circumferential direction,
The first wall of the nuclear fusion device according to claim 1, wherein a slit is provided between the divisions to form a thermal deformation space. 6. The first wall of the nuclear fusion device according to claim 1, wherein a soft copper buffer material is provided in the radial direction with a plurality of notches along the circumferential direction to form a thermal deformation space. 7. The first wall of the nuclear fusion device according to claim 1, wherein a copper wire mesh copper mesh is provided in the buffer material region to secure a heat deformation space.