JPH05234743A - Manufacture of superconducting coil - Google Patents

Abstract

PURPOSE:To facilitate connection of a superconducting wire element to an exterior by reducing a distortion generated at the strand and to improve a flow of refrigerant. CONSTITUTION:After a superconductor 1 filled with superconducting elements 3 and a cooling channel 2 formed with a passage 4 therein are separately manufactured, both are superposed and spirally formed so that the wire elements 3 hardly move, thereby reducing a stress to be applied thereto. Thus, deterioration of performance of the elements 3, quench and fretting can be prevented. Further, a pressure loss of the passage 4 can be reduced, and a cooling effect of the superconductor 1 can be improved. Moreover, since the superconductor 1 and the channel 2 are formed in the separate structures, an external connection of the superconductor 1 is facilitated.

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.

[0002]

2. Description of the Related Art Cooling methods for superconducting coils include immersion cooling and forced cooling. The immersion cooling method is a method of immersing the entire coil in a cooling medium to cool it.
The forced cooling method is a method in which a cooling medium is forcibly supplied to the coil to cool it.

A conventional forced cooling type superconducting coil is one in which the superconducting element wire 3 is housed in a kind of pipe called a conduit 7 and the outside of the conduit 7 is covered with an insulating member 5, as shown in FIG. A coolant was flown through the conduit 7 to forcibly cool it.

[0004]

The conventional forced cooling type superconducting coil has the following problems. (1) There is a superconducting element wire that receives a large strain due to the bending work when winding a coil, and the bending work requires a large force. (2) When used, the superconducting element wire is mainly subjected to a radial force due to electromagnetic force. As shown in FIG. 3, when the void ratio is large (there are many gaps), the superconducting element wire moves to the outer peripheral side and is elongated in the longitudinal direction to generate strain. (3) It is necessary to take out the superconducting wire from the conduit at the coil end. (4) Since the outer periphery of the superconducting wire becomes a wetting edge, the wetting edge length becomes long and the pressure loss becomes large. (5) When used, the superconducting wire is likely to move due to electromagnetic force or fluid force, and this movement causes strain or stress in the wire, and the possibility of quenching (transition to normal conductivity) or fretting increases. (6) The material characteristics of the superconducting element wire may be deteriorated by the heat when welding the conduit. (7) When a superconducting material such as Nb ₃ S _n is used for the superconducting element wire, the strain caused by the reasons (1), (2), and (5) above causes performance such as a decrease in critical current. There is a risk of deterioration.

The present invention is intended to solve the above problems.

[0006]

According to the method of manufacturing a superconducting coil of the present invention, a superconducting wire in which a superconducting element wire is filled and a cooling channel in which a cooling passage through which a refrigerant flows are formed separately. The superconductor and the cooling channel are overlapped with each other to form a spiral shape.

[0007]

In the above, since the superconductor and the cooling channel have the separated structure, it is possible to counter the electromagnetic force and the fluid force by arranging the superconducting element wires densely, and also in the coil winding process. The bending strain can be reduced, and at the same time, the force required for processing can be reduced.

Further, it is not necessary to take out the superconducting element wire from the cooling channel at the conductor end unlike the conventional coil, and the deterioration of the superconducting element wire for welding the cooling channel is eliminated. The problem can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. This embodiment shown in FIGS. 1A and 1B has a rectangular tube shape in which a superconducting tube 1 having a superconducting wire 3 filled with a superconducting element wire 3 and a cooling passage 4 through which a refrigerant flows are formed. After the cooling channels 2 are separately manufactured, the superconductor 1 and the cooling channels 2 are overlapped with each other to form a spiral shape as shown in FIG. The solder 6 is soldered to the insulating material 5, and the insulating member 5 is provided on the outer side of the superposed conductor 1 and the cooling channel 2.

In the above, the superconducting coil is the superconductor 1.
Since the cooling channel 2 and the cooling channel 2 are separately manufactured and then overlapped with each other and formed into a spiral shape, the superconducting element wires 3 in the superconducting element 1 can be densely arranged and the superconducting element wires 3 can be arranged.
Is made difficult to move, and the length of the wetting edge of the cooling channel 2 is reduced to reduce the pressure loss.

Since the superconductor 1 and the cooling channel 2 are separated from the beginning, it is not necessary to take out the superconductor 1 from the cooling channel 2 at the conductor end. Further, when winding the coil, the superconductor 1 and the cooling channel 2 are separately bent, so that the maximum strain generated in the superconductor 1 by bending as shown in FIG. 2B is the superconductor 1 and the cooling channel. It becomes smaller than the case shown in FIG.

For example, when the superconductor 1 and the cooling channel 2 have the same size, the number is about half. Further, the force required for bending may be smaller than that of the integrated type.

Further, since the cooling channel 2 and the superconductor 1 are manufactured separately, there is no risk of deterioration of the superconductor 1 due to welding of the cooling channel 2. The heat transfer between the superconductor 1 and the cooling channel 2 is easily carried out by direct contact between the two or by a joint portion such as soldering 6 which is performed after bending, so that the heat transfer in the superconducting wire rod 1 is made between the wires. In addition to the above contact, it is easily performed by filling a metal such as solder, copper, aluminum or the like or a refrigerant.

As described above, since the superconducting element wire becomes difficult to move and the stress associated therewith can be reduced, it is possible to prevent the performance deterioration of the superconducting element wire and the occurrence of quenching or fretting. Further, since the pressure loss of the cooling passage can be reduced, the cooling effect of the superconductor can be improved, and since the superconductor and the cooling channel have different structures, the connection between the superconductor and the outside can be facilitated. became.

[0015]

According to the method of manufacturing a superconducting coil of the present invention, a superconductor filled with a superconducting element wire and a cooling channel having a cooling passage formed inside are separately manufactured, and then superposed on each other to form a spiral shape. By forming the superconducting element, the superconducting element becomes less liable to move, and the stress associated with it can be reduced, so that it is possible to prevent the performance deterioration of the superconducting element and the occurrence of quenching or fretting. Yes, again
Since the pressure loss in the cooling passage can be reduced, the cooling effect of the superconductor can be improved, and since the superconductor and the cooling channel have different structures, the superconductor can be easily connected to the outside.

[Brief description of drawings]

FIG. 1 is an explanatory view of a superconducting coil according to an embodiment of the present invention, in which (a) is a sectional view and (b) is an external view.

2A and 2B are explanatory diagrams of strain in bending of the superconducting coil according to the above-mentioned embodiment, FIG. 2A is a sectional view of the superconducting coil, and FIG. 2B is strain when the superconductor and the cooling channel are separately bent. And (c) is an explanatory view of strain when integrally bent.

FIG. 3 is a sectional view of a conventional superconducting coil.

[Explanation of symbols]

 1 superconductor 2 cooling channel 3 superconducting element wire 4 cooling passage 5 insulating member 6 solder

Claims (1)

[Claims] 1. A superconductor filled with a superconducting element wire and a cooling channel in which a cooling passage through which a refrigerant flows are formed separately, and then the superconductor and the cooling channel are overlapped to form a spiral shape. A method for manufacturing a superconducting coil, which comprises forming the superconducting coil.