JPS6258868A - Superconducting rotor and its preparation - Google Patents

Abstract

PURPOSE:To prevent each layer from being positionally shifted, by a method wherein a junction layer is formed between a high conductive metallic layer and a high strength metallic layer, and wherein the junction layer is fused with heat on shrinkage fit, and wherein the layers are jointed together. CONSTITUTION:A cold damper shield 1 is a multilayer structure consisting of a high strength metallic layer 3a, a juncture layer 9a, a high conductive metallic layer 2, a junction layer 9b, and a high strength metallic layer 3b in order from the outer peripheral side, and these layers are respectively formed by shrinkage fit. The wax material of silver solder, or the like is used for the junction layers 9a, 9b. The junction layers 9a, 9b are respectively fused on shrinkage fit, and the high strength metallic layer 3b and the high conductive metallic layer 2 on the inner diameter side and the high strength metallic layer 3a and the high conductive metallic metallic layer 2 on the outer diameter side are respectively and metallurgically jointed together. As a result, each layer can be prevented from being positionally shifted.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a superconductor in which four turns of a superconductor wire are covered with a room-temperature Dunburnold formed by a multilayer cylindrical structure used, for example, in a superconducting rotor of a superconducting turbine generator. Regarding the rotor.

[Technical background of the invention and its problems]

Conventional superconducting rotor 1: In the case of the conventional superconducting rotor 1, it shields the varying magnetic flux caused by load fluctuations, negative sequence currents, high-phase waves, etc. applied from the armature winding side, and also prevents the fluctuating magnetic field from being applied to the superconducting field windings. Two electromagnetic damper shields, a room-temperature damper shield and a low-temperature damper shield, are installed around the superconducting field windings to suppress eddy current loss generated in various parts due to fluctuating magnetic fields and dampen mechanical vibrations of the rotor. has been done.

Here, a conventional superconducting rotor will be explained with reference to FIG. Reference numeral 1 denotes a hollow cylindrical room-temperature damper shield l, which includes a highly conductive metal layer 2 formed of a hollow cylinder made of a highly conductive material such as copper, aluminum, or an alloy thereof, and this highly conductive metal layer 2. The metal layer 2 has a three-layer structure including high-strength metal layers 3i and 3b formed of a hollow outer periphery and a hollow inner cylinder made of a non-magnetic high-strength material on the outer periphery side and the inner cylinder side. Note that this high-strength material uses an age-hardening alloy whose strength can be increased by heat treatment such as bath ratio treatment and age-hardening treatment. °Also, on the inner diameter side of this normal temperature damper shield 1, there is a vacuum insulation layer 4.
and a radiant heat shield 5 are formed, and furthermore, a cryogenic refrigerant container 6 is disposed on the inner diameter side thereof, and an internal rotor 7 is housed inside the cryogenic refrigerant container 6. Furthermore, a slot 8 is formed in this internal rotor 7, and a superconducting winding is accommodated in this slot 8.

Note that the radiant heat shield 5 generally also serves as a low-temperature damper shield.

Since the room-temperature damper shield 1 is located at the outermost diameter of the rotor, a strong centrifugal force acts on it, and a strong electromagnetic force acts on the damper shield 2, which has relatively weak mechanical strength. In order to reinforce the conductive metal layer 2, a multilayer structure is adopted in which the conductive metal layer 2 is integrated with the high-strength metal layers 3m and 3b as described above.

These high-strength metal layers 3a and 3b are made of stainless steel, Inconel, titanium alloy, or the like, and are configured to sandwich a highly conductive metal 7112 therebetween. In general, shrink fitting, explosion bonding, etc. are considered methods for manufacturing such a multilayer cylinder.1 Shrink fitting is the simplest method, but when this multilayer structure is formed by general shrink fitting, Each layer was mechanically joined, and therefore, microscopically, there were many gaps 10 between each layer, as shown in FIG. For this reason, when the superconducting rotor is rotated at a high speed, there is a possibility that the superconducting rotor is rotated at a high speed, and there is a possibility that the superconducting rotor becomes misaligned. In particular, when the temperature of the rotor rises, the misalignment becomes more likely to occur. In addition, in shrink fitting, each layer is mechanically joined, so if a hollow cylinder cracks in two, the tightening force due to cracking will be relaxed, causing a sudden shift between the eyebrows and a collapse of the overall balance. It could have happened.

Furthermore, when a multilayer structure is formed by explosive bonding, each layer is joined like a metal without any gaps, so that no deformation occurs due to centrifugal force. However, it is technically difficult to manufacture a long multi-layered cylindrical object by m-layering, and it has not yet been put to practical use.1. In addition, it has the disadvantage of causing large deformation during explosive bonding, making it unsuitable for producing long multilayered cylindrical objects.

[Purpose of the invention]

The present invention was made in order to solve the above-mentioned drawbacks of the conventional superconducting rotor, and provides a superconducting rotor and The purpose is to provide a manufacturing method thereof.

[Summary of the invention]

In order to achieve the above object, the present invention forms a normal temperature damper shield by fitting a hollow inner cylinder and a hollow outer cylinder made of a high-strength material to the inner cylinder side and outer peripheral side of a hollow cylinder made of a highly conductive material, In the superconducting rotor that covers the superconducting windings with this room-temperature damper shield, a bonding layer is provided between each of the hollow inner cylinder, hollow cylinder, and hollow outer cylinder, and these are shrink-fitted to form the room-temperature damper shield. The first gist is the characteristic superconducting rotor.

In the second invention, a first bonding layer made of a brazing material is formed on the outer circumferential side of the hollow inner cylinder made of a high-strength material, and the first bonding layer is formed on the outer circumferential side of the hollow inner cylinder through this first bonding layer. A hollow cylinder made of a highly conductive material is shrink-fitted and bonded at a predetermined temperature higher than the melting point of the brazing material, and then a second bonding layer made of the brazing material is formed on the outer periphery of the hollow cylinder. and a room-temperature damper shield is formed by shrink-fitting a hollow outer cylinder made of a high-strength material at a predetermined temperature higher than the melting point of the brazing material to the outer peripheral side of the hollow cylinder via the second bonding layer. The gist of this paper is a method for manufacturing a superconducting rotor.

This will be explained with reference to the figures. In FIG. 1, 1 is a normal temperature damper shield, and this normal temperature damper shield 1 is
High-strength metal layer 3a in order from the outer circumferential side.

Bonding layer 9a, highly conductive metal layer 2. It has a multilayer structure consisting of a bonding layer 9b and a high-strength metal layer 3b, and these layers are each formed by shrink fitting. A brazing material such as silver solder is used for the bonding layers 9a and 9b.

In addition, these bonding layers 9a and 9b are bath melted during shrink fitting, respectively.
The high-strength metal layer 3b and the high-conductivity metal layer 2 on the inner diameter side and the high-strength metal layer 3a and the high-conductivity metal layer 2 on the outer diameter side are metallically bonded to each other, respectively.The bonding layers 9a and 9b are The materials and forming method of the high conductive metal layer 2 and the high strength metal layer 3a,
It is preferable to select it arbitrarily based on the relationship with the material of 3b. For example, the high-strength metal layer is an N1-based age-hardening temperature alloy (Inconel 7).
18. Inconel
-4V) etc. are effective.

In addition, pure copper or a Cu-Cr alloy is effective for the highly conductive metal layer, and if the working stress is large, Cu-ρ, -7-
, A Hata Kokakinada; Female parent φ71 Next, we will explain the manufacturing method of the above-mentioned room-temperature damper shield 1. As an example, in each layer of the room-temperature damper shield 1, the highly conductive metal layer 2 is made of a Cu-Cr alloy. A case in which the high-strength metal layers 3a and 3b are made of austenitic steel (9TM-286) and the bonding layer is made of Ag--Pb solder will be described with reference to FIG.

Solution treatment was performed in advance at 950C to 1100G.

Hollow inner cylinder 1 made of AsTM-286 alloy, which is a high-strength metal 3b subjected to age hardening treatment at 700'C~goor.
A thin Ag-Pb solder plate 19b having a thickness of 0.5 to 1.0 IIm is attached to the outer periphery of the solder plate 3b as shown in FIG.

Cu-Cr was then heated to 450 r to 500 G.
Insert the hollow cylinder 12 of the alloy as shown in No. 311(b)E.
- Shrink fit into the hollow inner cylinder 13b wrapped with a Pb solder thin plate.

At this time, the Ag--Pb solder thin plate 19b is melted by the heat during shrink fitting. Thereafter, as shown in FIG. 3(c), a thin Ag--Pb solder plate 19m having a thickness of 0.5 to 1.01 mm is wrapped around the outer periphery of the hollow cylinder 12 and fixed by spot welding. Next, the N286 alloy hollow outer cylinder 13a, which has already been subjected to solution treatment 1 and age hardening treatment, is heated at 450 t:' to 500 C in Fig. 3 (d).
) Insert the knee as shown in 5 and shrink-fit it into the hollow cylinder 12 around which the thin Pb solder plate 19a is wrapped. This poet g-p
b The thin solder plate 19a is melted and metallically connected to the hollow cylinder 12 and the hollow outer cylinder 13a, thereby forming the room temperature damper shield 1.
is formed.

As described in 5 above, the highly conductive metal layer 2 and the high strength metal layer 3a,
A bonding layer 9a, Ti) and a bonding layer 9b were formed between the bonding layer 9a and the bonding layer 3b, respectively, and were integrated, resulting in a bonding layer 9m as shown in FIG.

9b is formed to widen the gap 5, and these layers are bonded metallically. For this reason, when the superconducting rotor is rotated at high speed, as shown in Figure 4, the high strength against collapse is increased based on the torque difference between each 11), and the resistance against collapse is increased due to the local temperature difference. Resistance is also increased, making it possible to reduce the possibility of slippage occurring during high-speed, long-term operation.

In addition, if a crack occurs in any layer of the room-temperature damper shield 1, the presence of the bonding layer 9m + 9b will prevent the conventional phenomenon of a sudden shift between the layers or sudden loss of balance due to the presence of the bonding layer 9m + 9b. It can be alleviated.

Furthermore, a hollow cylinder 12 of Cu-Cr alloy is inserted into a hollow inner cylinder 13b of 286 alloy.
Since the thin solder plate 19 can be melted and the thin Ag-pb solder plate is shrink-fitted at 450 to 500 C, the hollow cylinder 12 of Cu-Cr alloy can be melted at this temperature.
The age hardening treatment can be performed simultaneously, reducing the working time.

Further, the above-mentioned embodiment can be carried out by using conventional shrink-fitting equipment as is, without using any special equipment.

In the above embodiment, a Cu-Cr gold alloy was used for the hollow cylinder 12, but in order to achieve higher strength, a Cu-Cr-Z
[The same effects and effects as above can be obtained by using an alloy.

In addition, although Ag-Pb solder was used for the bonding layer, Ag-pb
Not limited to solder, Ag-Cd solder, Sn
It is also possible to use one additional pb solder.

Next (two examples will be described).

Hollow inner cylinder 13 of ASTM-A286 alloy before solution treatment
Outer circumference E O of b, 5 to 1. A thin G-Pb solder plate 19b having a thickness of OS ml is wound around the plate and fixed by spot welding as shown in FIG. Thereafter, a pure copper hollow cylinder heated to 900 to 1100 C was heated to a mug as shown in Figure 3(b).
- Hollow inner cylinder 13b wrapped with pb solder thin plate 19b
Place doves on it. The Ag-pb solder melts due to the heat during this shrink fitting. Thereafter, as shown in FIG. 3(c), a thin Ag--Pb solder plate 19a is wrapped around the outer periphery of the hollow cylinder n and fixed by spot welding. Next, input STM-person 2 before solution treatment
As shown in FIG. 3(d), the hollow outer periphery 13a of 86 alloy is soldered with Ag-pb solder thin plate 19a at 900C-1100C.
Shrink-fit it onto the hollow cylindrical retainer wrapped around it. At this time Ag −
PB solder thin plate 19! is melted and metallically combined with the hollow cylinder 12 and the hollow outer cylinder 13a, forming the room temperature damper shield 1.
is formed. After that, remove the entire room temperature damper shield 1 by 6
50C to 800C, hollow inner cylinder 13b, hollow outer circumference 13
m aging treatment).

By manufacturing according to the above method, the same functions and effects as in the embodiment described above can be obtained. Note that the above-mentioned example (
In the second case, the hollow cylinder 1 of the Cu-Cr alloy is
However, in this embodiment, the hollow inner cylinder 13b and the hollow outer cylinder 13a of the STM-286 alloy can be subjected to solution heat treatment at the time of shrink fitting.

Still other embodiments will be described. In the above-mentioned embodiment, the hollow inner cylinder 13b and the hollow outer cylinder 13 are made of ASTM-286 alloy which has already been subjected to solution treatment, the hollow cylinder J2 is made of pure copper, the bonding layer is made of Ag grout 5, and when shrink-fitting Even if the temperature is 650C to 800C and the same method is used to produce the same, the same effects as in the embodiment described above can be obtained. In this embodiment, the hollow inner tube 13b and the hollow outer tube 13a can be subjected to age hardening treatment at the time of shrink fitting.1 Next, another embodiment will be described.

Second, in the three embodiments described above, the hollow inner cylinder 1
3b and the hollow outer cylinder 13a, Ni-based age hardening alloy (for example, Inconel 718, Inconel X750, etc.) was used. The same effects as in the above embodiment can also be obtained by using a gold alloy such as Ti-62-4V.

Further, as a method of forming a bonding layer on the outer periphery of the hollow inner cylinder 13b and the hollow cylinder 12, in the above embodiment, the thin plates 19b and 19a of brazing material are wrapped around each other, but the bonding layer is formed by thermal spraying the brazing material. You may.

Furthermore, the wettability with the bonding layer can be improved by making the hollow inner part 413b and the hollow outer periphery 13a a heat-treatable alloy plated with Ni.

〔Effect of the invention〕

According to the present invention, the bonding layer is made of a highly conductive metal layer and a high strength gold G4.
The bonding layer is melted by the heat during shrink fitting, and the layers are bonded together, so each layer is metallically bonded and displacement of each layer is prevented, making it a highly reliable superconductor. A rotor can be provided.

Since the bonding layer is formed by melting the filter 5 material and metallically bonding each layer during shrink-fitting, conventional shrink-fitting equipment can be used and it can be easily manufactured without using special equipment. .

[Brief explanation of the drawing]

FIG. 1 shows a superconducting rotor according to an embodiment of the present invention with P6
Figure 2 is a cross-sectional view showing the normal temperature damper shield.
Figure 3 is an enlarged view of part A in the figure, Figure 3 is an explanatory diagram showing the manufacturing process of the room temperature damper shield shown in Figure 1, Figure 4 is a torque-displacement diagram showing the performance of the room temperature damper shield, Figure 5 is A cross-sectional view showing a conventional superconducting rotor, FIG.
It is an enlarged view of part B of meat. 1... Normal temperature damper shield 2... Highly conductive metal layer 3a, 3b... High strength metal layer 9a, 9b... Bonding layer 12... Hollow cylinder 13a... Hollow outer cylinder 13b
...Hollow circle WJ19a, 19b... Solder thin plate agent Noriyoshi Chika Yudo Hirofumi Mitsumata No. 1 Fig. 2 Torque → Fig. 4

Claims (9)

[Claims] (1) It has a superconducting winding and a room-temperature damper shield arranged to cover the outer periphery of the superconducting winding, and the room-temperature damper shield includes a hollow cylinder made of a highly conductive material, and a hollow cylinder made of a highly conductive material. In a superconducting rotor formed of a hollow inner cylinder and a hollow outer cylinder made of a high-strength material fitted on the inner and outer peripheral sides, a first A bonding layer and a second bonding layer are provided, and the hollow inner cylinder, the hollow cylinder, and the first hollow outer cylinder are provided.
A superconducting rotor characterized in that a room-temperature damper is formed by shrink-fitting a bonding layer and a second bonding layer. (2) A first bonding layer made of a brazing material is formed on the outer periphery of a hollow inner cylinder made of a high-strength material, and the melting point of the brazing material is applied to the outer periphery of the hollow inner cylinder through this first bonding layer. A hollow cylinder made of a highly conductive material is bonded by shrink fitting at the above predetermined temperature, and then a second bonding layer made of a brazing material is formed on the outer circumferential side of the hollow cylinder. A method for producing a superconducting rotor, characterized in that a hollow outer cylinder made of a high-strength material is shrink-fitted to the outer circumferential side of the hollow cylinder at a predetermined temperature equal to or higher than the melting point of the brazing material to form a room-temperature damper shield. . (3) The method for manufacturing a superconducting rotor according to claim 2, wherein the hollow inner tube and the hollow outer tube are made of a high-strength material plated with nickel. (4) The high strength material is an age hardening temperature alloy subjected to solution treatment and age hardening treatment, and the high conductivity material is Cu.
-Cr alloy or Cu-Cr-Zr alloy, the bonding layer is formed of a brazing material of Ag-Pb, Ag-Cd, or Sn-Pb, and the predetermined temperature is 400°C.
Claim 2 characterized in that the temperature is ~500°C
The method for manufacturing a superconducting rotor according to item 1 or 3. (5) The high-strength material is an age-hardening alloy, the highly conductive material is Cu, the bonding layer is formed of nickel solder or silver solder, and the predetermined temperature is 90%
The method for manufacturing a superconducting rotor according to claim 2 or 3, wherein the temperature is 00 to 1100°C. (6) The high-strength material is an age-hardened alloy subjected to solution treatment, the highly conductive material is Cu, the bonding layer is formed of silver solder, and the predetermined temperature is 65%.
The method for manufacturing a superconducting rotor according to claim 2 or 3, wherein the temperature is 0 to 800°C. (7) The age hardening alloy is ASTM-A286 alloy, Inconel 718, Inconel X750 or Ti-6A.
7. The method for manufacturing a superconducting rotor according to claims 4 to 6, characterized in that the superconducting rotor is one of l-4V alloys. (8) The first and second bonding layers are formed by wrapping a thin plate-shaped brazing material around the outer periphery of the hollow inner cylinder and the outer periphery of the hollow cylinder. The method for manufacturing a superconducting rotor according to item 7. (9) The first and second bonding layers are formed by thermally spraying a brazing material onto the outer periphery of the hollow inner cylinder and the outer periphery of the hollow cylinder. A method for manufacturing a superconducting rotor.