JPH0737714A - Manufacture of superconducting coil - Google Patents

Abstract

PURPOSE:To provide a method of manufacturing a superconducting coil which can reduce the steps of mechanical processings and enhance application efficiency of material. CONSTITUTION:On the occasion of manufacturing a second conduit for reinforcement accommodating superconducting stranded wires and a coolant within a groove 2a which is formed in a spiral shape in the longitudinal direction, a long length raw material E is bent with pressure to a winding core 11 and is then wound in a spiral shape. By winding the length length raw material E in a spiral shape, steps of mechanical process can be reduced to enhance the application efficiency of the material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a superconducting coil, and more particularly to a method for manufacturing a large-sized superconducting coil having a double conduit structure.

[0002]

2. Description of the Related Art A superconducting coil used in a tokamak type fusion reactor or the like has a spiral shape, and a conduit for holding a superconducting twisted wire and a refrigerant is composed of a first conduit and a second conduit. Some have a double structure.

FIG. 14 shows an example of such a superconducting coil. In the figure, reference numeral 1 is a thin, long hollow first conduit made of stainless steel or titanium material. The first conduit 1 contains a superconducting stranded wire 3 together with a refrigerant such as liquid helium. It has a role of holding the refrigerant in an airtight state. Reference numeral 2 is a second conduit which is made of stainless steel or the like, has a groove 2a formed in its longitudinal direction, and is formed into a spiral shape with a predetermined turn. The second conduit 2 accommodates the first conduit 1 in a groove space formed by overlapping the grooves 2a so as to face each other, and reinforces the strength of the first conduit 1 to enhance superconductivity by electromagnetic force. It has a role of preventing deformation of the twisted wire 3.

FIGS. 15 and 16 are explanatory views of a method for manufacturing the second conduit 2 of such a superconducting coil as disclosed in, for example, Japanese Patent Laid-Open No. 173604/1990. First, in the method shown in FIG. 15, the second conduit 2 is formed by cutting a plate material having a predetermined thickness into a spiral shape with a predetermined number of turns, and then forming a groove 2a in the spiral shape body by machining. . On the other hand, in the method shown in FIG. 16, a plate material having a predetermined thickness is cut into a concentric ring shape having a predetermined width, and then the groove 2a is formed in the ring material by machining. Then, after the ring material having the groove 2a is cut into a semi-ring shape, the second conduit 2 is formed by welding and joining the joint portions 4 while displacing them in a difference in diameter.

In this way, after the right-handed and left-handed second conduits 2 have been processed and manufactured, respectively, the wound first processed conduit 1 is sandwiched by a pair of second conduits 2 and assembled into the groove 2a. , Manufactures superconducting coils.

[0006]

However, in the conventional method for manufacturing a superconducting coil as described above, in order to manufacture the second conduit 2, machining is required in many steps such as cutting a plate and forming grooves. Therefore, there is a problem that it takes a long time to manufacture and the manufacturing cost becomes high. Further, when cutting the plate material, there is a problem that a large amount of unnecessary portions are generated and the material utilization efficiency is low.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method of manufacturing a superconducting coil which can reduce machining and improve material utilization efficiency. To do.

[0008]

According to the present invention, there is provided a first conduit for keeping airtightness, which contains a superconducting stranded wire and a refrigerant, and is formed in a spiral shape, and is used at least on one side to be superposed. A method for manufacturing a superconducting coil, comprising: a pair of reinforcing second conduits each having a groove for accommodating a first conduit in a longitudinal direction thereof; While being pressed and bent into a mold, it is spirally wound and molded.

[0009]

According to the present invention, when the long material is already grooved, the second conduit is formed by spirally winding the long material while pressing and bending the long material into the winding form. Produced. When the long material is not grooved, the second conduit is formed by spirally winding the long material while pressing and bending it into a winding die, and then performing groove processing on these. It is produced by. It should be noted that the second conduit that does not require grooving is manufactured simply by spirally winding a long material that has not been grooved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. Example 1. 1 is a perspective view of a winding device for manufacturing a second conduit for explaining a method of manufacturing a superconducting coil according to a first embodiment of the present invention.

In the figure, 10 is a winding drum rotatable in the direction of the arrow, 11 is a winding die fixed on the winding drum 10, and its outer diameter is equal to the spiral inner diameter of the second conduit 2, 1
2 is a second conduit 2 having one end Ea fixed to the winding form 2
A press device for winding a linear long material E for forming into a spiral shape while pressing and bending it toward the winding form 11 side, and 13 is pressed and bent around the winding form 11 by the pressing device 12. It is a retainer that pressurizes and fixes the long material E to the winding form 11. Here, there are various shapes of the long material E for forming the second conduit 2, as will be described later, but at least a fixed length having a rectangular cross section (a length considering the ease of manufacturing). ). Since the structure of the superconducting coil is the same as that described with reference to FIG. 14, the description will be omitted.

Next, the operation of the winding device according to the first embodiment will be described. First, one end Ea of the long material E is fixed to the outer peripheral portion of the winding form 11 by welding or the like. Thereafter, the winding material 10 is rotated while the long material E is pressed and bent on the winding die 11 by the press device 12, and the long material E is rotated.
Wind around the outer peripheral surface of the winding form 11. In this case, the wound long material E is sequentially attached to the long material E with a predetermined pitch at a predetermined pitch, and is fixed to the winding form 11 side. Then, when the long material E is wound by a certain length, the next long material E is welded to this long material E by splicing and joining, and these long material E are sequentially arranged on the outer peripheral surface side of the winding form 11, Then, the long material E wound around the winding form 11 is wound on the outer peripheral surface side. In this case, the retainer 13 used for fixing the long material E on the previous circumference is sequentially replaced with the long material E wound on the next circumference. When a spiral body of a predetermined number of turns is formed by the long material E, the spiral body is subjected to necessary mechanical processing or the like to manufacture the second conduit 2.

As described above, in the method for manufacturing the superconducting coil according to the first embodiment, when the second conduit 2 is manufactured, the plate material is not cut into a spiral shape, but the long material E is pressed onto the winding form 11. Since the material is bent and wound, unnecessary portions of the plate material are not cut off, so that the material utilization efficiency is increased. Further, as compared with the machining such as cutting the plate material, the bending of the long material E does not require a large machining machine and the work is completed in a short time. Therefore, in the method for manufacturing the superconducting coil, the second conduit is used. 2 can be manufactured at low cost in a short time.

Example 2. In the first embodiment described above, the linear long material E is simply pressed against the winding die 11 by the pressing device 12 to be pressed and bent, while being wound in a spiral shape. As shown by, the winding device is provided with a bender 14, and the roller 1 of the bender 14 is provided.
The long material E is pre-bent to some extent through the long material E between the 4a, and then the long material E is wound around the winding form 11.

According to the second embodiment, since the long material E is pre-bent by the bender 14, in addition to the effect of the first embodiment, the springback at the time of pushing and bending the long material E can be reduced. Therefore, the residual stress due to the bending of the rolled up spiral body can be minimized, and for example, the annealing step for stress relief can be eliminated.

Embodiment 3. In the first embodiment described above, the linear long material E is simply pressed against the winding die 11 by the pressing device 12 to be pressed and bent while being wound in a spiral shape. As shown by, the long material E is wound around the winding form 11 while being pulled by the tensioner 15.

In the third embodiment, a bending stress exceeding the yield stress is applied to the long material E via the tensioner 15, so that the long material E can be easily wound without the pressing device 12. It can be rolled into a mold 11. In this case, the tensioner 15 is composed of a pair of sandwich plates 15a for sandwiching the long material E, and bolts 15b for pressing the sandwich plate 15a toward the long material E. The long material E can be slid while sandwiching the long material E with an arbitrary surface pressure. Therefore, the tensioner 15 can be used to apply a required tension to any long material E, and the long material E can be easily wound around the winding form 11. Incidentally, 16 is a pedestal for receiving the reaction force of the tensioner 15, and 17 is a tension measuring device.

Example 4. In the first embodiment described above, one end Ea of the linear long material E is fixed to the winding form 11 by welding or the like,
While the elongate device e is pressed and bent by the pressing device 12 against the winding form 11 and is wound in a spiral shape, in the third embodiment, as shown in FIG. A fixing jig 18 is provided, and one end Ea of the long material E is joined to the fixing jig 18 by welding or the like, and then the fixing jig 18 is attached to the winding form 11 via a bolt 18a. .

If the long material E is directly fixed to the winding form 11 by welding, it becomes difficult to remove the spirally wound long material E from the winding form 11 after the winding process is completed. In the fourth embodiment, the fixing jig 18 is provided, and the one end Ea of the long material E is joined to the fixing jig 18 by welding or the like to fix the spiral body wound around the winding form 11 to the fixing jig 18. It can be easily removed from the winding form 11. Note that the fixing jig 18 can be removed from the spiral body without difficulty.

Next, the manufacturing method of the second conduit 2 in each of the above embodiments will be described in more detail with reference to FIGS. 5 to 13 while showing the concrete shape of the long material E.

In FIG. 5, the unprocessed primary elongate material E1 is grooved to form a secondary elongate material E2 having a groove 2a in the longitudinal direction, and then this secondary elongate material E2 is wound. It is shown that the second conduit 2 is formed by spirally winding using the device. In this case, a pair of the secondary long materials E2 may be spirally wound at once in a state where the grooves 2a face each other and are overlapped.

In FIG. 6, the unrolled primary long material E1 is spirally wound by using a winding device to first form the spiral body F1 and then the spiral body F1.
It is shown that the second conduit 2 is formed by forming the groove 2a in the. In this case, since the groove processing is performed after the winding processing, the groove 2a is not deformed by the bending during the winding processing, and the second conjet 2 having good dimensional accuracy is formed.

In FIG. 7, a secondary elongated material E3 having hollow holes 5 formed by drilling holes in the longitudinal direction of the unprocessed primary elongated material E1 is wound into a spiral shape using a winding device. The spiral body F2 is formed by winding the
It is shown that the second conduit 2 is molded by horizontally cutting at the position of the broken line L. In this case, the pair of second conduits 2 can be formed by one winding process, and the secondary long material E3 is formed as the pair of secondary long material E2.
Since they are integrated with each other, the winding process can be easily performed without causing the positional deviation with respect to each other as compared with the case of winding the pair of secondary long material E.

In FIG. 8, the groove 2 is formed by cold drawing.
It shows that the second conduit 2 is formed by spirally winding the secondary long material E2 integrally formed with a using a winding device. In this case, since the secondary long material E2 having the groove 2a is manufactured by cold drawing, machining (grooving) can be reduced and the manufacturing time of the second conduit 2 can be shortened.

In FIG. 9, a pair of secondary elongate materials E2 are superposed, and a core 19 is put in a groove space formed by a pair of opposed grooves 2a. It is shown that the second conduit 2 is formed by spirally winding. In this case, since the core 19 is provided in the pair of secondary long material E2, the groove 2a of the secondary long material E2 is not deformed by bending during winding processing.

FIG. 10 shows the case where the secondary long material E2 is formed in consideration of the shape deformation after the winding process.
2 shows that the sectional shape of 2 is determined. Ie 2
Regarding the cross-sectional shape of the next long material E2, the wall thickness on the outer peripheral surface side (left side in the drawing) during winding is increased, and the wall thickness on the inner peripheral surface side (right side in the drawing) is reduced. Therefore, during winding, tensile stress acts on the outer peripheral surface side and compressive stress acts on the inner peripheral surface side, so that the cross section of the secondary long material E2 after winding has an appropriate shape as shown by the broken line. .

FIG. 11 shows a case where a reinforcing core 20 is inserted around the welded joint Eb in the groove 2a of the secondary elongated material E for reinforcement during winding processing. Since the welded joint portion Eb is apt to be weaker in strength than other portions, the bending phenomenon is likely to occur at the welded joint portion Eb during winding processing. Therefore, the reinforcing core 20 is inserted in the groove 2a of the secondary long material E2 at the front and rear positions of the welding joint Eb, and the welding joint Eb is reinforced by the reinforcing core 20, and the winding is wound. The bending phenomenon of the welded joint Eb during processing was prevented.

In this case, as shown in FIG. 12, the intermediate portion of the reinforcing core 20 arranged at the position of the welded joint Eb is made solid, and the welded joint is connected to the reinforcing core 20. A hollow hole 20a having a diameter gradually increasing toward the end side of the reinforcing core 20 away from Eb was provided. Therefore, the strength of the middle portion of the reinforcing core 20 is maximized, and the strength is reduced toward the end side. As a result, the bending of the welded joint Eb of the secondary long material E2 and its vicinity is smoothly performed.
If the hollow hole 20a of the reinforcing core 20 is formed into a conical shape or a pyramidal shape, the welded joint Eb of the secondary long material E2 and the bending in the vicinity thereof can be more smoothly performed.

Incidentally, in each of the above-mentioned embodiments, the long material E is subjected to the intermediate welding before the winding process.
As shown by 3, the long materials E may be bent one by one by the winding device, and then the bent long materials E may be welded to each other. In this method, it is necessary to consider the return of the curvature of the long material E due to the spring back, but since the welding of the welded joint Eb does not occur, the welded joint Eb can be prevented from being deformed (such as a waist bending phenomenon).

Although the groove 2a is formed in all of the pair of second conduits 2 for accommodating the first conduit 1, the first conduit 1 is formed only in the second conduit 2 on one side.
A second conduit 2 in which a deep groove 2a for accommodating is formed, the second conduit 2 on the other side is not formed, and the second conduit 2 in which the groove 2a is formed is not formed in the groove 2a.
You may make it overlap so that it may cover. In this case, any of the second conduits 2 can be easily manufactured by the method shown in each of the above embodiments.

[0031]

As is apparent from the above description, according to the present invention, the first conduit for keeping airtightness, which contains the superconducting stranded wire and the refrigerant, is formed in a spiral shape and is used in superposition. In a method for manufacturing a superconducting coil, the method includes a pair of reinforcing second conduits each having a groove for accommodating the first conduit in a longitudinal direction formed on at least one side thereof. Since the long material is pressed and bent into a winding shape and wound into a spiral shape, the plate material is cut in comparison with the case where the second conjet is formed from the plate material in manufacturing the superconducting coil. It is possible to eliminate the machining process and to improve the material utilization efficiency.

[Brief description of drawings]

FIG. 1 is a perspective view of a winding device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a winding device according to a second embodiment of the present invention.

FIG. 3 is a perspective view of a winding device according to a third embodiment of the present invention.

FIG. 4 is a perspective view of a main part of a winding device according to a fourth embodiment of the present invention.

FIG. 5 is a diagram for explaining a step of manufacturing a second conduit from the first long material according to the present invention.

FIG. 6 is a diagram for explaining a step of manufacturing a second conduit from a second long material according to the present invention.

FIG. 7 is a diagram for explaining a step of manufacturing a second conduit from a third long material according to the present invention.

FIG. 8 is a second view of a long material having a core according to the present invention
It is a figure for demonstrating the process of manufacturing a conduit.

FIG. 9 is a diagram for explaining a step of manufacturing a second conduit from a fourth long material according to the present invention.

FIG. 10 is a diagram for explaining a step of manufacturing a second conduit from a fifth long material according to the present invention.

FIG. 11 is a diagram for explaining a step of manufacturing a second conduit from a long material having a reinforcing core at a welded joint according to the present invention.

FIG. 12 is a sectional view showing a reinforcing core according to the present invention.

FIG. 13 is a diagram for explaining a step of manufacturing a second conduit from a long material which is not spliced according to the present invention.

FIG. 14 is a perspective sectional view showing a superconducting coil.

FIG. 15 is a diagram illustrating a conventional method of manufacturing a second conduit.

FIG. 16 is a diagram illustrating a conventional method of manufacturing a second conduit.

[Explanation of symbols]

 1 1st conduit 2 2nd conduit 2a Groove 3 Superconducting twisted wire 11 Winding type E Long material E1 Primary long material E2 Secondary long material E3 Secondary long material

Claims (1)

[Claims] 1. A first conduit for keeping airtightness for accommodating a superconducting stranded wire and a refrigerant, and a first spiral conduit formed in a spiral shape and extending in the longitudinal direction on at least one side used in an overlapping manner. A method of manufacturing a superconducting coil, comprising: a pair of reinforcing second conduits each having a groove for accommodating a conduit;
A method of manufacturing a superconducting coil, which comprises winding a long material into a winding form and winding the conduit in a spiral shape.