JPH1155908A - Junction method for coil end of generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable junction method for coil ends of a generator which can reduce the occurrence percentage of defects in a brazed part. SOLUTION: Brazing material is arranged in a group of coil element wires 3 which are obtained by heating coil element wires 2 at 300 deg.C or over, and then, annealing them to remove the insulation of the element wire applied to the periphery, and cleaning and dissolving the material face of the coil element wire 2, where the element wire insulation is removed, for 1 μm or more by inorganic acid, and bundling the cleaned and dissolved coil element wires 2, and fairing and trimming them so that the average value of the gaps between the coil element wires 2 may be 100 μm or under and that the average value of the gaps between the coil element wires 2 and a bundled-wire box 1 to be joined with the wires may be 200 μm or under, and then, they are integrated into the bundled-wire box 1, and these are heated at a specified temperature for joining.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining the ends of a generator coil, and more particularly to a method for joining the ends of a generator coil suitable for reducing the rate of occurrence of brazing defects.

[0002]

2. Description of the Related Art A rotating electric machine, for example, a generator such as a turbine generator or a water turbine generator, employs a structure in which a coil conductor is cooled by a cooling medium as its capacity increases. Recently, due to the remarkable increase in capacity, a structure in which the coil conductor is directly cooled from the inside is adopted. As disclosed in JP-A-8-103046, JP-A-8-205443, etc., this direct cooling structure includes a bundle for supplying and discharging a cooling medium and electrically connecting the coils. A wire box is provided at the end of the stator coil.

[0003] The above bundled box body is joined by brazing.
It is provided at the end of the stator coil. This brazing joint
This is performed through several processing steps. First, wire insulation applied to the outer peripheral portion of the coil wire and impurities adhering to the surface thereof are removed. Next, the coil wires from which the wire insulation and impurities have been removed are bundled and shaped and adjusted to predetermined dimensions. Next, a brazing filler metal is arranged between the coil wires and assembled into a bundle box. Then, they are heated and joined at a predetermined temperature.

[0004]

The brazing connection between the bundle box and the stator coil is required not to cause a defect in the brazed portion. If a defect occurs in the brazed portion, cooling water as a cooling medium stays in the defective portion as dead water, and the brazing material or coil conductor is selectively corroded (gap corrosion) due to a change in corrosion potential. I will. When this corrosion is combined with the brazing defect, the corrosion extends to the entire length of the brazing portion, and eventually the generator stops operating due to water leakage.

[0005] It is very difficult to eliminate defects occurring in the brazed portion. However, the present inventors conducted various investigations on defects generated in the brazed portion in order to reduce the incidence of defects generated in the brazed portion.
Researched. As a result, several causes of defects occurring in the brazed portion were found.

First, it was found that the gap between the coil wires and the gap between the coil wire and the bundle box were not appropriate, and the gaps were small or large in some places.
If the gap is not appropriate, when the brazing material is heated and melted, it is difficult for the brazing material to flow into a narrow gap. On the other hand, where the gap is large, the brazing material flows out. As a result, the brazing material is not uniformly dispersed, and a brazing defect occurs.

Further, it has been found that the activation of the surface of the coil wire and the bundle box is insufficient, and the bonding is performed with impurities remaining on each surface. If impurities remain on the surface of the coil wire and the bundle box, the heated and molten brazing material is less likely to adhere to the portion. As a result, the joining by the brazing material becomes defective, and a brazing defect occurs.

Further, it has been found that the heating temperature (brazing temperature) fluctuates when the bundle box housing the coil element group is being heated. When the brazing temperature fluctuates, the degree of flow of the molten brazing material also fluctuates, and in some places, the brazing material flows abnormally. As a result, the brazing material is not uniformly dispersed, and a brazing defect occurs.

As described above, the inventors of the present invention have found that the cause of the occurrence of the brazing defect is removal of the wire insulation applied to the outer peripheral portion of the coil wire, which is a series of brazing joining processing steps, It has been found that the process is to remove impurities adhering to the outer peripheral surface of the wire, to shape the wire, and to heat the bundle box housing the group of coil wires.

The present invention has been made in view of the above points, and has as its object to remove wire insulation applied to the outer peripheral portion of a coil wire, and to remove the outer insulation surface of the coil wire. Reliable power generation that can reduce the incidence of defects that occur in brazed parts during removal of adhered impurities, shaping, and heat treatment of bundled boxes housing coil groups. An object of the present invention is to provide a method of joining the ends of a machine coil.

[0011]

According to the present invention, a coil wire is heat-annealed at a predetermined temperature to an outer peripheral portion thereof in order to obtain a method of joining a generator coil end which achieves the above object. The coil obtained by removing the wire insulation, dissolving and washing the material surface of the coil wire from which the wire insulation has been removed with an inorganic acid, bundling the melt-washed coil wires, shaping them into predetermined dimensions, and arranging the coil. A brazing material is arranged in a group of wires, assembled into a bundle box, and heated at a predetermined temperature to be joined.

More specifically, the coil wire is heated and annealed at a temperature of 300 ° C. or higher to remove the wire insulation applied to the outer periphery thereof, and the material surface of the coil wire from which the wire insulation has been removed. Is dissolved and washed with an inorganic acid for at least 1 μm, the melted and washed coil wires are bundled, and the average value of the gap between the coil wires is 1
A brazing material is arranged in a coil wire group obtained by shaping and arranging so that the average value of the gap between the coil wire and the binding wire box to be joined is 200 μm or less. It is assembled into a body and heated at a predetermined temperature to join.

The average value of the gaps between the coil wires and between the coil wires and the bundle box is determined by pressurizing the coil wire group or dissolving and cleaning the coil wires with an inorganic acid. Alternatively, the adjustment is performed by either pressure shaping of the binding box or machining of the binding box. The wire insulation provided on the outer peripheral portion of the coil wire may be removed by machining before or after heat annealing.

It is preferable to use a binding box having a brazing material escape groove as the binding box.

In order to achieve the above object, in order to obtain a method for joining the ends of a generator coil, the present invention removes the wire insulation applied to the outer periphery of the coil by heating and annealing the coil at a predetermined temperature. The material surface of the coil wire from which the wire insulation has been removed is dissolved and washed with an inorganic acid, the melted and washed coil wire is bundled, shaped and adjusted to a predetermined size, and the shaped and adjusted coil wire is formed. A brazing material is arranged in the coil element group obtained by applying the corrosion-resistant paint, assembled into a bundle box, and heated at a predetermined temperature to be joined.

The above-mentioned corrosion-resistant paint has an emissivity of 0.5.
The above ceramic materials are used. As the binding box, it is preferable to use a binding box provided with a brazing material escape groove.

In order to obtain a method of joining the ends of a generator coil which achieves the above object, the present invention provides a method of heating and annealing a coil wire at a predetermined temperature to remove the wire insulation applied to the outer periphery thereof. The material surface of the coil wire from which the wire insulation has been removed is dissolved and washed with an inorganic acid, and the melt-washed coil wire is bundled, shaped and adjusted to a predetermined size, and a brazing material is added to the obtained coil wire group Is arranged and assembled into a binding box, which is heated and joined at a predetermined temperature to apply a corrosion-resistant dissimilar metal to the surface of the coil wire group exposed in the binding box.

As the corrosion-resistant dissimilar metal, tin, nickel, or silver is used. As the binding box, it is preferable to use a binding box provided with a brazing material escape groove.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view for explaining brazing joining between a stator coil and a bundle box of a generator according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG. It is a sectional view in the state where a stator coil was settled in a cable box.

In the drawings, reference numeral 1 denotes a bundle box provided by brazing to an end of a stator coil of a generator.
It is almost pentagonal. The bundle box 1 supplies and discharges a cooling medium (cooling water) that cools the stator coil from the inside, and performs electrical connection between the stator coils. The supply / discharge mouthpiece 8 for performing the above is joined by brazing. In addition, the lower part on one end side, that is,
Under the supply / discharge fitting 8, a plurality of current-carrying connecting pieces 9 for electrically connecting the stator coils are joined by brazing.

On the other hand, a box-shaped housing chamber 1a for accommodating the coil element group 3 of the stator coil is provided on the other end side of the bundle box 1, and one side thereof (supply / discharge fitting). 8 and the surface opposite to the current-carrying connection piece 9) and the upper surface are open. A cooling medium supply / discharge chamber 1b is formed adjacent to the accommodation room 1a and has substantially the same size as the axial section of the coil element group 3 accommodated in the accommodation room 1a. ing. Cooling water is supplied from the supply / discharge port 8 to the cooling medium supply / discharge chamber 1b or from the cooling medium supply / discharge chamber 1b to the supply / discharge port 8 on the side opposite to the opening side of the cooling medium supply / discharge chamber 1b. A communication pipe 1c for guiding is provided.

The coil wire 2 has a hollow structure for flowing cooling water.

The bundle box 1 of the present embodiment has the above-described structure, and is made of a copper material which is the same material as the coil wire 2.

Next, a description will be given of the brazing connection between the bundle box 1 and the stator coil.

In the brazing of the stator coil and the bundle box 1, the rate of occurrence of defects generated at the time of brazing is reduced, and even if the generator is operated for a long period of time, a leak does not occur. I have to do it. Therefore, in the present embodiment, brazing is performed in the following processing steps.

(1) Processing Step I The coil element wire 2 is cut into a predetermined size.
The wire insulation (insulating resin, glass fiber) applied to the coil wire 2 to be incorporated into the wire is removed by machining.

(2) Processing Step II The coil wires 2 are bundled and annealed by heating at a temperature of 300 ° C. or more. Thereby, the wire insulation applied to the coil wire 2 is completely removed. The wire insulation may be removed only by heat annealing or may be removed by mechanical processing after heat annealing. (3) Processing Step III The coil wire 2 from which the wire insulation has been removed is dissolved and washed with an inorganic acid such as phosphoric acid. At this time, in order to keep the surface of the coil wire 2 activated, the material surface of the coil wire 2 is dissolved and removed by 1 μm or more.

(4) Processing Step IV A coil wire group 3 in which a required number of coil wires 2 whose surfaces are activated are bundled is shaped and arranged to required dimensions. Specifically, the coil wire group 3 is pressure-shaped so that the gap between the coil wires 2 is 100 μm or less on average. The gap between the coil wires 2 may be adjusted by dissolving and washing with an inorganic acid such as phosphoric acid.

Here, the average value of the gap between the coil wires 2 is obtained by the following equation (1).

[0031]

(Equation 1)

L ₀ is the width of the wire assembly portion (housing chamber 1 a) of the bundle box 1, l _i is the width of each coil wire 2,
n is the number of stacking stages of the coil wires 2.

Next, the end of the coil wire group 3 incorporated in the storage chamber 1a of the bundle box 1, that is, between the coil wires 2 exposed on the side of the cooling medium supply / discharge chamber 1b, between the coil wires 2 and the bundle. A corrosion-resistant paint 4 is applied to the surface of the coil element wire group 3 facing the cooling medium supply / discharge chamber 1b between the wire box body 1 and dried at 60 ° C. to 150 ° C. for about 2 hours to remove the solvent. . In the present embodiment, it is composed of a mixture of chromium oxide, graphite, silicate, iron oxide, a solvent, etc., has an emissivity of 0.5 or more (preferably 0.9 or more) after drying and solidifying, and can withstand the brazing temperature. A ceramic material is used as the corrosion-resistant paint 4.

Next, when the coil element group 3 is assembled into the binding box 1, the gap between the coil element 2 and the binding box 1 is set to be 200 μm or less on average. The body 1 (accommodation chamber 1a) is machined, or the binding box 1 is press-shaped from outside. The average value of the gap between the coil element wire 2 and the bundle box 1 is obtained by the above-described equation (1).

(5) Processing Step V The arrangement between the rows of the wires of the coil wire group 3 obtained through a series of processing steps of the processing steps I to IV, and the coil wires 2 and the bundle box A predetermined amount of the brazing material 5 is arranged between the body 1 and the brazing material 5 and assembled into the accommodation room 1 a of the binding box 1. Next, accommodation room 1
a brazing material 5 is placed on the coil wire group 3 incorporated in
Put the lid 7 on it. Then, the whole is heated at 700 ° C. to 800 ° C. by harmonic heating or the like. Thereby, the coil element group 3 is joined to the bundle box 1.

(6) Process VI In the process VI, the process of applying the corrosion-resistant paint 4 to the ends of the coil wire group 3 has been described. After joining the group 3 and the bundle box 1, the ends of the coil strand group 3 may be plated with a corrosion-resistant dissimilar metal (either one may be selected).

In this case, the end of the coil wire group 3 incorporated in the housing chamber 1a of the bundle box 1, that is, the cooling medium supply / discharge chamber 1b
The surface of the coil wire group 3 facing the cooling medium supply / discharge chamber 1b side between the coil wires 2 exposed on the side, between the coil wires 2 and the bundle box 1, and the corrosion-resistant dissimilar metal at 80 ° C. To a tin plating solution (chemical reduction plating solution having a tin ion concentration of 0.1 mol / l)
Immersion for 10 minutes and tin plating. As for the thickness of the tin plating film, the liquid temperature, tin ion concentration, and immersion time may be changed as necessary. In addition, as the corrosion-resistant dissimilar metal, nickel, or
It may be silver.

In the present embodiment, the case where the structure shown in FIG. 1 is employed as the binding box 1 has been described. However, the binding box 1 having the structure as shown in FIG. 3 is employed. You may. The bundle box 1 shown in FIG.
b is provided with a brazing material escape groove 6, so that excess brazing material is accumulated.

As described above, according to the present embodiment, the wire insulation applied to the coil wire 2 is removed by heating and annealing at a temperature of 300 ° C. or more, and the surface of the material of the coil wire 2 is treated with an inorganic acid such as phosphoric acid. Is dissolved and removed by 1 μm or more, so that the material surface of the coil wire 2 is activated, and the bonding with the brazing material can be improved.

Further, even if the wire insulation is removed by machining and then heat annealing is performed at a temperature of 300 ° C. or more, and then dissolution removal with an inorganic acid is performed, heat annealing is performed at a temperature of 300 ° C. or more. Even if the wire insulation is removed by machining, and then the solution is removed by dissolution with an inorganic acid, the surface of the material of the coil wire 2 is activated and the bonding with the brazing material can be improved.

Further, according to the present embodiment, the coil element group 3 is press-shaped and shaped so that the gap between the coil elements 2 is 100 μm or less on average, and the coil element group 3 is bundled. The bundle box 1 (accommodating chamber 1a) is machined or bundled so that the gap between the coil element wire 2 and the bundle box 1 is 200 μm or less on average when assembled into the box 1. Since the wire box 1 is externally pressurized and shaped, the coil wire 2
The gap between the coil wires 2 and the bundle box 1 can be properly adjusted, and the brazing material melted by heating can be evenly and uniformly dispersed in the coil wire group 3.

Further, according to the present embodiment, the ends of the coil wire group 3 incorporated in the storage chamber 1a, that is, between the coil wires 2 exposed on the side of the cooling medium supply / discharge chamber 1b, the coil wires 2 and the bundle Since the corrosion-resistant paint 4 is applied to the surface of the group of coil wires 3 facing the cooling medium supply / discharge chamber 1b between the wire box 1 and the package, and sealed in a lump, a defect occurs in the brazed portion. Even so, it is possible to suppress the start of corrosion of the portion and to prevent the surplus brazing material from attaching to portions other than the brazed portion.

Further, instead of applying the corrosion resistant paint 4,
After joining the coil element group 3 and the binding box 1, the coil exposed to the end of the coil element group 3 incorporated in the accommodation room 1 a of the binding box 1, that is, the cooling medium supply / discharge chamber 1 b side. Corrosion-resistant dissimilar metals are plated between the wires 2, between the coil wires 2 and the bundle box 1, and on the surface of the coil wire group 3 facing the cooling medium supply / discharge chamber 1b. As described above, even if a defect occurs in the brazed portion, the initiation of corrosion in that portion can be suppressed.

Further, according to the present embodiment, the emissivity is 0.5 or more (preferably) as the corrosion-resistant paint 4 applied to the end of the coil wire group 3 incorporated in the accommodation room 1a of the bundle box 1. Is 0.9 or more), so that the melting state of the brazing material can be measured by the brightness of the surface of the coil wire group 3 facing the cooling medium supply / discharge chamber 1b side, and appropriate temperature control can be performed. In addition, it is possible to prevent the brazing material from abnormally flowing due to uneven heating temperature distribution during brazing. this is,
This is an effective means for quality control.

Further, according to the present embodiment, the bundled box 1 provided with the brazing material escape groove 6 is employed, and the excess amount of the brazing material that has melted and flowed is stored in the brazing material escape groove 6. With this configuration, it is possible to prevent the brazing material from entering and clogging into the hollow interior of the coil element wire 2 and obstructing the flow path of the cooling water.

The present inventors took a vertical cross-sectional image of the end of the stator coil of the generator by using X-ray CT in the longitudinal direction of the coil in order to examine the defect state of the brazed portion. Non-destructive inspections between the coil strand group and the bundle box and between the coil strand group and the lid were performed and evaluated for 12 examples.

For the evaluation, the defect occurrence rate represented by the ratio of the cumulative length of the brazing defect to the brazing length (design set value) in the length direction of the coil, and the end of the stator coil of the generator were determined. The length of corrosion from the brazed portion at the end of the coil group 3 on the cooling medium supply / exhaust chamber side when left for 180 days in water at a water temperature of 70 ° C., pH ≒ 3, and dissolved oxygen of 20 ppb was measured. It was evaluated by the corrosion rate obtained by dividing by the standing time.

Table 1 summarizes the evaluation results and the execution conditions of the twelfth embodiment.

[0049]

[Table 1]

The following can be confirmed from Table 1.

As in Example 2, it was confirmed that in the case where the coil element wire was not dissolved and removed by an inorganic acid such as phosphoric acid in the treatment step III, the rate of occurrence of brazing defects was high and the corrosion rate was high. . Therefore, it is understood how important it is to dissolve and remove the coil wire by an inorganic acid such as phosphoric acid, that is, to activate the surface of the coil wire material.

Further, in the case of employing the bundle box without the brazing material escape groove as in the fourth embodiment, the surplus brazing material melted at the time of brazing enters the hollow inside of the coil wire, Hole clogging was confirmed. Example 5
Uses a bundled box body in which no brazing material escape groove is provided as in Example 4, but since the end of the coil element group is coated with a ceramic-based corrosion-resistant paint, Excessive brazing material is prevented from adhering to parts other than the attached parts.

Further, it was confirmed that the rate of occurrence of brazing defects tended to be higher in the case of heat-annealing treatment at a low temperature as in Example 7 because of the wire alignment property.

[0054]

According to the present invention, the coil wire is heated to 300.degree.
The wire insulation applied to the outer peripheral portion was removed by heat annealing at the above temperature, and the material surface of the coil wire from which the wire insulation had been removed was dissolved and washed with an inorganic acid for 1 μm or more, and then dissolved and washed. The coil wires can be bundled and shaped and arranged so that the average value of the gap between the coil wires is 100 μm or less, and the average value of the gap between the coil wires and the bundle box to be joined is 200 μm or less. Since the brazing material was arranged in the group of coil wires and assembled into the bundle box, and this was heated and joined at a predetermined temperature, the material surface of the coil wires was activated,
It is possible to improve the bonding between the brazing material and the appropriate degree of the gap between the coil wires and between the coil wires and the bundle box. It can be evenly and evenly dispersed.

According to the present invention, the coil wire is heated and annealed at a predetermined temperature to remove the wire insulation applied to the outer periphery thereof, and the material of the coil wire from which the wire insulation has been removed. The surface is dissolved and washed with an inorganic acid, the melted and cleaned coil strands are bundled, shaped and aligned to a predetermined size, and the shaped and aligned coil strands have a corrosion resistance of a ceramic material having an emissivity of 0.5 or more. The brazing material was arranged in the coil wire group obtained by applying the conductive paint and assembled into the bundle box, and this was heated at a predetermined temperature and joined so that a defect occurred in the brazed part. In addition, it is possible to suppress the start of corrosion of the portion and to prevent the surplus brazing material from attaching to portions other than the brazed portion.
In addition, the melting state of the brazing material can be measured by the brightness of the surface of the coil wire group, and appropriate temperature control can be performed, thereby preventing abnormal flow of the brazing material due to uneven heating temperature distribution during brazing. .

Further, according to the present invention, the coil wire is heat-annealed at a predetermined temperature to remove the wire insulation applied to the outer periphery thereof, and the material surface of the coil wire from which the wire insulation has been removed is removed. After dissolving and washing with an inorganic acid, the melted and washed coil strands are bundled, shaped and arranged to a predetermined size, a brazing material is arranged in the obtained coil strand group, assembled into a bundle box body, and Heating and joining at a temperature to apply a corrosion-resistant dissimilar metal to the surface of the coil wires exposed inside the bundle box, so that even if a defect occurs in the brazed part, Start can be suppressed.

Therefore, according to the present invention, the removal of the wire insulation applied to the outer peripheral portion of the coil wire, the removal of impurities adhering to the outer peripheral surface of the coil wire, the shaping and straightening, and the coil It is possible to provide a highly reliable method of joining the ends of a generator coil, which can reduce the incidence of defects generated in a brazed portion in a heat treatment of a bundled box housing a group of wires.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view for explaining brazing joining between a stator coil and a bundle box of a generator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 (cross-sectional view in a state where a stator coil is accommodated in a bundled box body).

FIG. 3 is a perspective view of a bundled box provided with a brazing material escape groove;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bundling box body, 1a ... Accommodation room, 1b ... Cooling medium supply / discharge chamber,
1c: communication pipe, 2: coil wire, 3: coil wire group, 4
... corrosion resistant paint, 5 ... brazing material, 6 ... brazing material escape groove, 7
... Lid, 8 ... Supply / discharge fitting, 9 ... Electrical connection piece.

Continued on the front page (72) Inventor Yoichi Kotani 3-1-1, Sachimachi, Hitachi-shi, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (72) Inventor Yuji Iwaki 3-1-1, Sachimachi, Hitachi-shi, Ibaraki Inside Hitachi, Ltd.Hitachi Plant (72) Inventor Tatsuro Ishizuka 3-1-1 Sachimachi, Hitachi, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Plant (72) Inventor Yasuyoshi Watanabe, Yachimachi, Hitachi, Ibaraki 1-1 1-1, Hitachi, Ltd.Hitachi Factory (72) Inventor Yamazaki Sachi 502, Kandatecho, Tsuchiura-shi, Ibaraki Pref.

Claims (9)

[Claims] 1. A coil wire is heated and annealed at a predetermined temperature to remove wire insulation applied to an outer peripheral portion thereof, and a material surface of the coil wire from which the wire wire has been removed is treated with an inorganic acid. Melting and washing, brazing the coil wires that have been dissolved and washed, shaping and arranging them to predetermined dimensions, disposing a brazing material in a group of coil wires obtained, assembling them into a bundled box, and putting this at a predetermined temperature. A method of joining the ends of the generator coil to be joined by heating. 2. A method of joining a coil end of a generator coil by brazing a group of coil wires composed of a plurality of coil wires and a bundle box, wherein the coil wires are heat-annealed at a temperature of 300 ° C. or more. Then, the wire insulation provided on the outer peripheral portion is removed, and the material surface of the coil wire from which the wire insulation has been removed is dissolved and washed with an inorganic acid for 1 μm or more, and the dissolved and washed coil wire is removed. Bundling, the average value of the gap between the coil wires is 1
00 μm or less, a group of coil wires obtained by shaping and shaping so that the average value of the gap between the coil wire and the wire box to be joined is 200 μm or less, A method for joining the ends of a generator coil, wherein the joining is performed by brazing. 3. An average value of a gap between the coil strands and a gap between the coil strand and the bundled box box to be joined is determined by pressurizing and shaping the coil strand group or the coil. 3. The generator coil end according to claim 2, wherein the wire is dissolved and washed with an inorganic acid, or the wire box is pressurized and shaped, or adjusted by machining the wire box. Joining method. 4. The method according to claim 2, wherein the wire insulation applied to the outer periphery of the coil wire is removed by machining before or after the heat annealing. How to join the ends of the generator coil. 5. A coil wire is heated and annealed at a predetermined temperature to remove the wire insulation applied to the outer periphery thereof, and the material surface of the coil wire from which the wire insulation has been removed is treated with an inorganic acid. After being melt-washed, the coil wires that have been melt-washed are bundled, shaped and sized to a predetermined size, and a corrosive paint is applied to the shaped and wrapped coil wire to form a coil wire group obtained. A method of joining the ends of a generator coil in which materials are arranged and assembled into a bundled box body, which is heated and joined at a predetermined temperature. 6. A ceramic material having an emissivity of 0.5 or more is used as the corrosion-resistant paint.
The method for joining the ends of a generator coil according to the above description. 7. A coil wire is heated and annealed at a predetermined temperature to remove the wire insulation applied to the outer periphery thereof, and the material surface of the coil wire from which the wire insulation has been removed is treated with an inorganic acid. Melting and washing, brazing the coil wires that have been dissolved and washed, shaping and arranging them to predetermined dimensions, disposing a brazing material in a group of coil wires obtained, assembling them into a bundled box, and putting this at a predetermined temperature. A method for joining the ends of a generator coil, wherein the coil ends are heated and joined, and a corrosion-resistant dissimilar metal is applied to the surface of the group of coil wires exposed in the bundle box. 8. The method according to claim 7, wherein tin, nickel or silver is used as said corrosion-resistant dissimilar metal.
The method for joining the ends of a generator coil according to the above description. 9. A bundle box having a brazing material escape groove as said bundle box.
A method for joining the ends of a generator coil according to claims 5 and 7.