US20060102469A1 - Electroplating apparatus - Google Patents
Electroplating apparatus Download PDFInfo
- Publication number
- US20060102469A1 US20060102469A1 US11/159,344 US15934405A US2006102469A1 US 20060102469 A1 US20060102469 A1 US 20060102469A1 US 15934405 A US15934405 A US 15934405A US 2006102469 A1 US2006102469 A1 US 2006102469A1
- Authority
- US
- United States
- Prior art keywords
- clip
- interior
- component
- electroplating solution
- electroplating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
- H02K15/12—Impregnating, heating or drying of windings, stators, rotors or machines
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D21/00—Processes for servicing or operating cells for electrolytic coating
- C25D21/10—Agitating of electrolytes; Moving of racks
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/04—Tubes; Rings; Hollow bodies
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
- H02K15/0056—Manufacturing winding connections
- H02K15/0068—Connecting winding sections; Forming leads; Connecting leads to terminals
- H02K15/0081—Connecting winding sections; Forming leads; Connecting leads to terminals for form-wound windings
- H02K15/0093—Manufacturing or repairing cooling fluid boxes, i.e. terminals of fluid cooled windings ensuring both electrical and fluid connection
Definitions
- Water-cooled stator bars for electrical generators are comprised of a plurality of small rectangular solid and hollow copper strands brazed to one another to form a bar.
- the ends of the strands are brazed to an end fitting, typically referred to as-stator bar clip.
- a cover is brazed to the clip window.
- the end fitting serves as both an electrical and a cooling flow connection for the stator bar.
- the hollow end fitting typically includes an enclosed chamber for ingress or egress of stator bar cooling liquid, typically deionized water. At one end, the end fitting receives the ends of the strands of the stator bar. The fitting and the peripherally outermost copper strands of the stator bar are brazed to one another. The opposite end of the fitting is connected to a stator cooling conduit.
- stator bar cooling liquid typically deionized water.
- Liquid cooled stator bar clips have gone through design changes over the years. However, they typically contain mixed solid and hollow strands brazed to one another, and a cover brazed to a clip window. During operation, the hollow strands carry water to cool off the bar. Over time, leaks can develop about the connection between the stator bar ends and the stator bar fitting, between cover and clip as well as between adjacent strands. Leaks may also occur at various plumbing connections. It is believed that the major leak mechanism is a crevice corrosion process which initiates in the braze alloy at the interior surface of the braze joint. Crevice corrosion is a localized form of corrosion usually associated with a stagnant solution on the micro-environmental level.
- crevice corrosion is initiated by changes in local chemistry within the crevice, such as shift to phosphorous acid conditions in the crevice. Stagnant water in the chamber of the fitting is in contact with the braze alloy and the copper strands. This coolant contact with the braze joint and cooper strands is believed to cause corrosion and consequent leakage.
- a leak site is identified by several different tests, such as vacuum decay and traceable Helium test.
- An epoxy barrier coating method has been used as a leak repair and prevention method.
- An example of an epoxy barrier coating method is disclosed in U.S. Pat. No. 5,605,590, the disclosure of which is incorporated herein by this reference.
- This epoxy barrier coating has been applied to provide protection against water initiated corrosion mechanisms along the brazed length of the strand package.
- Epoxy coating is manually injected. The voids and air pockets are possible during injection.
- the process is labor intensive and requires 100% inspection. As a result, the process can be labor intensive, takes a long time to complete, and can produce defects.
- the invention proposes an electroplating method to deposit a thin layer of metallic barrier coating on a part of or the entire interior surface of a liquid-cooled stator bar clip.
- the metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion susceptible region(s) such as clip-to-strand braze joints.
- Different materials may be deposited, such as copper or nickel as the metallic barrier coating.
- the invention may be embodied in an apparatus for electroplating an interior of a component, comprising: an inflow tube for flowing electroplating solution to an interior of said component; an outflow tube for flowing electroplating solution out of an interior of said component; a pump for conducting electroplating solution through said inflow tube and for drawing said electroplating solution through said outflow tube; an anode disposed in said electroplating solution and electrically connected to a power supply; and said component being electrically connected to said power supply as a cathode.
- the invention may also be embodied in a method of sealing a stator bar with an interior liquid pass for flow of coolant forming at least a portion of said stator bar, comprising electroplating at least a portion of an interior wetted surface of said stator bar.
- the invention may also be embodied in a method of sealing interior surfaces of a fitting receiving a stator bar end, to define a seal substantially impermeable to liquid, the fitting having a chamber for receiving a liquid through an opening in the fitting and said chamber being in communication with hollow strands forming at least a portion of said stator bar, said method comprising the steps of: disposing an electroplating solution in said chamber; disposing an anode of the metal or metal alloy to be deposited in said electroplating solution; connecting said anode to the positive terminal of a current source as a cathode; electrically connecting said stator bar to the negative terminal of said current source; and establishing an electrical potential between said anode and said cathode to initiates electrophoretic migration of metal ions from the anode to the electrically conductive inner surface of the component.
- the invention is also embodied in stator bar end and a fitting receiving the end to define a seal substantially impermeable to liquid, the fitting having a chamber for receiving a liquid through an opening in the fitting and in communication with hollow strands forming at least a portion of said stator bar and for flow of the liquid through the hollow strands, wherein at least a portion of an interior surface of said fitting has a metallic layer disposed thereon, wherein said metallic layer is deposited by electroplating.
- FIG. 1 is a schematic illustration of a liquid-cooled stator winding arrangement illustrating the stator bars and end fittings coupled to inlet and outlet coolant headers;
- FIG. 2 is a schematic cross-section of a plating set-up for plating the interior of a component, such as a stator bar clip;
- FIG. 3 is a schematic illustration of a plating set-up for simultaneous plating wherein the bar is flooded with circulating solution.
- Water-cooled stator bars for electrical generators are comprised of a plurality of small rectangular solid and hollow copper strands which are brazed to one another and brazed to an end fitting.
- the end fitting serves as both an electrical and a hydraulic connection for the stator bar.
- the end fitting typically includes an enclosed chamber for ingress or egress of stator bar cooling liquid, typically deionized water. Another opening of the end fitting receives the ends of the strands of the stator bar, the fitting and peripherally outermost copper strands of the stator bar being brazed to one another. Over time, leaks have variously developed about the connection between the stator bar ends and the stator bar fitting as well as between adjacent strands.
- the leak mechanism is due to a crevice corrosion process which initiates in the braze alloy at the interior surface of the braze joint. Crevice corrosion is initiated by changes in local chemistry within the crevice, such as shift to phosphorous acid conditions in the crevice.
- an electroplating method is proposed to deposit a thin layer of metallic barrier coating on the entire interior surface of liquid-cooled stator bars' water pass, or selectively on target areas, e.g., with high corrosion risks or otherwise having a high leak potential.
- the metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion susceptible region(s) such as clip-to-strand braze joints. Concurrently the coating has the capability to repair and prevent substantially all other types of leaks.
- FIG. 1 there is illustrated a liquid-cooled stator winding arrangement used in a typical liquid-cooled generator.
- a stator core having stator core flanges 12 and core ribs 14 is illustrated, with stator bars 16 passing through radially extending slots and terminating at opposite ends in end fittings 18 and 20 .
- Inlet hose 22 connects inlet fitting 18 to an inlet coolant header 24 and outlet hose 26 connects the outlet fitting 20 to an outlet coolant header 28 .
- Each stator bar 16 includes a plurality of hollow and solid copper strands. respectively disposed in side-by-side and superposed relation one to the other.
- the fitting for example, fitting 20 , includes a clip 30 formed of an electrically conductive material, such as copper.
- the clip comprises a body having a rectilinear opening at one end for receiving the strands of the stator bar 16 .
- a-copper tube 32 which serves as both an electrical connection and a hydraulic connection for flowing liquid coolant, e.g., deionized water, into or from the chamber 34 defined by the stator bar clip 30 and the exposed ends of the hollow and solid copper strands.
- the liquid in the chamber either flows into the fitting and through the hollow strands for cooling purposes when the fitting comprises an inlet fitting or receives the liquid coolant from the hollow strands for egress when the fitting is employed as an outlet fitting.
- the solid and hollow strands are brazed to one another, and a cover is brazed to clip window. These junctions are among the potential sites for leaks over time.
- the interior of the stator bar clip 30 including the corrosion susceptible braze joint between the clip 30 and the stator bar 16 , and the cover to clip braze seal, are electroplated so that a thin metallic layer is deposited on the entire interior surface.
- the metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion and/or leak susceptible region(s) such as the clip-to-strand braze joints and the cover-to-clip braze seal.
- Electroplating is facilitated by isolating the target stator bar clip, including the braze joint between it and the stator bar, such as by partial disassembly to provide access to the end of the clip remote from the stator bar.
- FIG. 2 a suitable assembly for electroplating the stator bar clip is schematically illustrated by way of example.
- plastic tubing 40 is securely coupled to the clip and extends up and away from the clip to define a plating solution bath upper surface 42 whereas the plating solution 44 will fill the chamber 34 defined by the stator clip.
- a pump 46 is provided to circulate plating solution 44 through the bath defined by the interior of the stator clip 30 and the interior of the tubing 40 .
- the plating solution may be initially loaded to the clip interior through the tubing 40 , or the pump can load the bath through inflow tube 48 .
- a reservoir of plating solution (not shown) is provided and operatively coupled-to the pump.
- recirculating flow tube 50 recirculates fluid to the pump (and reservoir, if any) and removes any gas, such as hydrogen bubbles, trapped against the uppermost portion of the clip interior. The resultant circulating flow advantageously promotes agitation.
- the anode 52 is a length of 10 gauge insulated copper wire stripped for several inches and rolled into a coil to reduce its overall dimensions.
- a copper wire is just one example of a consumable metal source that may be provided as the anode.
- Other alternatives include a metal mesh structure. Electrical contact between the anode and the component being plated should of course not occur. Therefore, in an exemplary embodiment the anode is inserted into, e.g., a double walled porous bag 54 of non-conductive material to prevent electrical contact but to allow solution access.
- the anode is connected to a suitable poser supply (a 2-3 V DC power supply was used in a test apparatus).
- the device itself is electrically coupled to the power supply as a cathode, e.g., via contact 56 .
- the reservoir may be closed remote from the access tube.
- a recirculating system may be provided wherein the remote end is not closed, but instead the flow is through the clips 30 at each end of the stator bar(s), and the interior of both clips and the respective braze joints are plated simultaneously, as schematically illustrated in FIG. 3 .
- plating solution reservoirs 60 , 62 are disposed in flow communication with each clip, and a pump 64 is provided to circulate the plating solution through the clips and bar 16 .
- the device is heated, e.g. with heating tape, to between 40 and 50° C. Heating may also be accomplished with an in-line heater in the electrolyte return tube.
- An exemplary acid copper electroplating solution is a mixture of e.g., water, sulfuric acid, copper sulfate, and a trace of hydrochloric acid. To this mixture a number of organic constituents are added that serve to regulate and distribute the delivery of, e.g., copper to the surface being plated.
- the two basic organic additives are commonly referred to as the “brightener/leveler” and the “carrier”.
- An electroplating cell is typically comprised of a (non-metallic) container full of the electroplating solution in flow communication with the area or component surface to be treated and a source of plating metal ions, as the anode.
- the electroplating cell is comprised of the component (clip 30 ) interior 34 , the access tubing 40 interior volume, the inflow and outflow tubes 48 , 50 , and the remote reservoir for the solution (if provided) and, as the anode, the coiled copper wire 52 , or other consumable metal source, disposed within the access tubing 40 and/or clip 30 .
- This ion supply must be capable of continuous sourcing into a near short circuit load.
- a typical copper electroplating bath has an effective full load operating “impedance” that ranges from 0.025 Ohms and 0.015 Ohms.
- the surface for receiving the electroplated coating referred to as the cathode, in this case the clip, the stator bar, and the braze joint therebetween, is connected to the negative terminal of the current source.
- Deposition of, e.g., copper in this example, on the target component occurs when an electrical potential is established between the anode and the cathode (target component).
- the resulting electrical field initiates electrophoretic migration of copper ions from the anode to the electrically conductive surface of the cathode, where the ionic charge is neutralized as the metal ions plate out of solution.
- a uniform, thin coating of smooth, bright copper is deposited on the target surface(s).
- pressure treatment may be applied by defining the water pass system as a closed loop that can be sealed and pressurized. Additionally, locating the return flow tube to draw fluid from the vertically upper portion of the stator clip, as mentioned above, facilitates the removal of trapped air or evolved gas to facilitate uniform plating.
- the electroplating process is continued until a deposit layer of about 1 to 3 mm is achieved.
- the process can be ceased at any time simply by disengaging the power source.
- the plating of the braze joint may be accomplished as a double-layered plating with a first plating followed by a second plating applied over the first plating layer.
- a double layered plating provides enhanced durability as compared to a single layered plating particularly where the plating coatings have selective properties; for example, an underlying plated film having strong corrosion resistance and a second plated film applied for air tightness, durability and corrosion resistance.
- the water pass of the stator bars and/or the clips may be plated before assembly and then plating can again be carried out after assembly to plate the braze joints, to effectively provide a double layered plating in certain areas or on certain parts.
- all of the joints which have the potential for forming a leakage path are electroplated.
- the existing leak or leaks at the stator bar end connections of a generator in the field are repaired.
- a seal is provided which will ensure against the formation of leakage paths in the future. That is, the electroplating not only isolates the liquid coolant from the brazing material and seals between the joints of adjacent strands and the outermost strands, but can be used to deposit a layer of material over, to seal, the entire interior surface of the coolant flow path, whereby all potential leakage paths are sealed to prevent future leaks.
- the present invention is particularly applicable to field repairs of existing generators, it may also be applied to generators during initial manufacture to provide protection against future leakage.
- the method disclosed herein is capable of applying a coating over the entire wetted surface of the flow system, the method can address the clip crevice corrosion leak issue and also other leak issues in liquid cooled generators.
- the method embodying the invention may used to address clip crack leaks, clip window leaks, plumbing and fitting leaks, and connection ring leaks.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Power Engineering (AREA)
- Windings For Motors And Generators (AREA)
- Electroplating Methods And Accessories (AREA)
- Motor Or Generator Cooling System (AREA)
Abstract
The interior of a stator bar clip that is joined to the end of a stator bar is electroplated so that a metallic barrier coating overlies the braze joint between the stator bar and the clip to define a seal at and around the joint that is substantially impermeable to liquid.
Description
- Water-cooled stator bars for electrical generators are comprised of a plurality of small rectangular solid and hollow copper strands brazed to one another to form a bar. The ends of the strands are brazed to an end fitting, typically referred to as-stator bar clip. A cover is brazed to the clip window. The end fitting serves as both an electrical and a cooling flow connection for the stator bar.
- The hollow end fitting typically includes an enclosed chamber for ingress or egress of stator bar cooling liquid, typically deionized water. At one end, the end fitting receives the ends of the strands of the stator bar. The fitting and the peripherally outermost copper strands of the stator bar are brazed to one another. The opposite end of the fitting is connected to a stator cooling conduit.
- Liquid cooled stator bar clips have gone through design changes over the years. However, they typically contain mixed solid and hollow strands brazed to one another, and a cover brazed to a clip window. During operation, the hollow strands carry water to cool off the bar. Over time, leaks can develop about the connection between the stator bar ends and the stator bar fitting, between cover and clip as well as between adjacent strands. Leaks may also occur at various plumbing connections. It is believed that the major leak mechanism is a crevice corrosion process which initiates in the braze alloy at the interior surface of the braze joint. Crevice corrosion is a localized form of corrosion usually associated with a stagnant solution on the micro-environmental level. Such stagnant microenvironments tend to occur in crevices such as micro surface voids formed during brazing, especially at the boundary of strands and braze alloy. Crevice corrosion is initiated by changes in local chemistry within the crevice, such as shift to phosphorous acid conditions in the crevice. Stagnant water in the chamber of the fitting is in contact with the braze alloy and the copper strands. This coolant contact with the braze joint and cooper strands is believed to cause corrosion and consequent leakage.
- Field repair of coolant leaks through the stator bar end connections has been successful. A leak site is identified by several different tests, such as vacuum decay and traceable Helium test.
- An epoxy barrier coating method has been used as a leak repair and prevention method. An example of an epoxy barrier coating method is disclosed in U.S. Pat. No. 5,605,590, the disclosure of which is incorporated herein by this reference. This epoxy barrier coating has been applied to provide protection against water initiated corrosion mechanisms along the brazed length of the strand package. Epoxy coating is manually injected. The voids and air pockets are possible during injection. Thus, the process is labor intensive and requires 100% inspection. As a result, the process can be labor intensive, takes a long time to complete, and can produce defects.
- There are also other leak issues in liquid cooled generators. Indeed, there are many types of leaks associated with water-cooled generators. Stator bar end crevice corrosion is the major one. But other leaks are caused by porosity, cracking and localized damage during manufacturing rather than as a result of corrosion.
- There is a need for an improved method for leak repair and prevention in liquid-cooled generators. In particular, there is a need for corrosion protection at the junction between the stator bars and their clips. The corrosion protection should be robust and be applicable to various stator bar clip designs, including clips for recessed braze, flush braze and raised hollow strand braze designs. There is also a need for an improved method to repair and prevent leaks within the generator water pass that arise from other causes.
- The invention proposes an electroplating method to deposit a thin layer of metallic barrier coating on a part of or the entire interior surface of a liquid-cooled stator bar clip. The metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion susceptible region(s) such as clip-to-strand braze joints. Different materials may be deposited, such as copper or nickel as the metallic barrier coating.
- Thus, the invention may be embodied in an apparatus for electroplating an interior of a component, comprising: an inflow tube for flowing electroplating solution to an interior of said component; an outflow tube for flowing electroplating solution out of an interior of said component; a pump for conducting electroplating solution through said inflow tube and for drawing said electroplating solution through said outflow tube; an anode disposed in said electroplating solution and electrically connected to a power supply; and said component being electrically connected to said power supply as a cathode.
- The invention may also be embodied in a method of sealing a stator bar with an interior liquid pass for flow of coolant forming at least a portion of said stator bar, comprising electroplating at least a portion of an interior wetted surface of said stator bar.
- The invention may also be embodied in a method of sealing interior surfaces of a fitting receiving a stator bar end, to define a seal substantially impermeable to liquid, the fitting having a chamber for receiving a liquid through an opening in the fitting and said chamber being in communication with hollow strands forming at least a portion of said stator bar, said method comprising the steps of: disposing an electroplating solution in said chamber; disposing an anode of the metal or metal alloy to be deposited in said electroplating solution; connecting said anode to the positive terminal of a current source as a cathode; electrically connecting said stator bar to the negative terminal of said current source; and establishing an electrical potential between said anode and said cathode to initiates electrophoretic migration of metal ions from the anode to the electrically conductive inner surface of the component.
- The invention is also embodied in stator bar end and a fitting receiving the end to define a seal substantially impermeable to liquid, the fitting having a chamber for receiving a liquid through an opening in the fitting and in communication with hollow strands forming at least a portion of said stator bar and for flow of the liquid through the hollow strands, wherein at least a portion of an interior surface of said fitting has a metallic layer disposed thereon, wherein said metallic layer is deposited by electroplating.
-
FIG. 1 is a schematic illustration of a liquid-cooled stator winding arrangement illustrating the stator bars and end fittings coupled to inlet and outlet coolant headers; -
FIG. 2 is a schematic cross-section of a plating set-up for plating the interior of a component, such as a stator bar clip; and -
FIG. 3 is a schematic illustration of a plating set-up for simultaneous plating wherein the bar is flooded with circulating solution. - Water-cooled stator bars for electrical generators are comprised of a plurality of small rectangular solid and hollow copper strands which are brazed to one another and brazed to an end fitting. The end fitting serves as both an electrical and a hydraulic connection for the stator bar. The end fitting typically includes an enclosed chamber for ingress or egress of stator bar cooling liquid, typically deionized water. Another opening of the end fitting receives the ends of the strands of the stator bar, the fitting and peripherally outermost copper strands of the stator bar being brazed to one another. Over time, leaks have variously developed about the connection between the stator bar ends and the stator bar fitting as well as between adjacent strands. It is believed, based on leak analysis results, that the leak mechanism is due to a crevice corrosion process which initiates in the braze alloy at the interior surface of the braze joint. Crevice corrosion is initiated by changes in local chemistry within the crevice, such as shift to phosphorous acid conditions in the crevice.
- There are also other leak issues in liquid cooled generators. Examples of other leaks in addition to the clip crevice corrosion leaks are clip crack leaks, clip window leaks, plumbing and fitting leaks, and connection ring leaks.
- Field repair of leaks through the stator bar end connections has only been moderately successful.
- In an embodiment of the invention, an electroplating method is proposed to deposit a thin layer of metallic barrier coating on the entire interior surface of liquid-cooled stator bars' water pass, or selectively on target areas, e.g., with high corrosion risks or otherwise having a high leak potential. The metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion susceptible region(s) such as clip-to-strand braze joints. Concurrently the coating has the capability to repair and prevent substantially all other types of leaks.
- Referring now to the drawings, particularly to
FIG. 1 , there is illustrated a liquid-cooled stator winding arrangement used in a typical liquid-cooled generator. A stator core havingstator core flanges 12 andcore ribs 14 is illustrated, withstator bars 16 passing through radially extending slots and terminating at opposite ends inend fittings Inlet hose 22 connects inlet fitting 18 to aninlet coolant header 24 andoutlet hose 26 connects the outlet fitting 20 to anoutlet coolant header 28. Eachstator bar 16 includes a plurality of hollow and solid copper strands. respectively disposed in side-by-side and superposed relation one to the other. The fitting, for example, fitting 20, includes aclip 30 formed of an electrically conductive material, such as copper. The clip comprises a body having a rectilinear opening at one end for receiving the strands of thestator bar 16. At the opposite end, there is provided an opening which in use is normally engaged witha-copper tube 32 which serves as both an electrical connection and a hydraulic connection for flowing liquid coolant, e.g., deionized water, into or from thechamber 34 defined by thestator bar clip 30 and the exposed ends of the hollow and solid copper strands. The liquid in the chamber either flows into the fitting and through the hollow strands for cooling purposes when the fitting comprises an inlet fitting or receives the liquid coolant from the hollow strands for egress when the fitting is employed as an outlet fitting. As mentioned above, the solid and hollow strands are brazed to one another, and a cover is brazed to clip window. These junctions are among the potential sites for leaks over time. - In an embodiment of the invention, the interior of the
stator bar clip 30, including the corrosion susceptible braze joint between theclip 30 and thestator bar 16, and the cover to clip braze seal, are electroplated so that a thin metallic layer is deposited on the entire interior surface. The metallic layer provides a corrosion resistant barrier coating to prevent water access to corrosion and/or leak susceptible region(s) such as the clip-to-strand braze joints and the cover-to-clip braze seal. - Electroplating is facilitated by isolating the target stator bar clip, including the braze joint between it and the stator bar, such as by partial disassembly to provide access to the end of the clip remote from the stator bar. Referring to
FIG. 2 , a suitable assembly for electroplating the stator bar clip is schematically illustrated by way of example. In the illustrated embodiment,plastic tubing 40 is securely coupled to the clip and extends up and away from the clip to define a plating solution bathupper surface 42 whereas theplating solution 44 will fill thechamber 34 defined by the stator clip. Apump 46 is provided to circulateplating solution 44 through the bath defined by the interior of thestator clip 30 and the interior of thetubing 40. The plating solution may be initially loaded to the clip interior through thetubing 40, or the pump can load the bath throughinflow tube 48. In the latter case, a reservoir of plating solution (not shown) is provided and operatively coupled-to the pump. In either case, recirculatingflow tube 50 recirculates fluid to the pump (and reservoir, if any) and removes any gas, such as hydrogen bubbles, trapped against the uppermost portion of the clip interior. The resultant circulating flow advantageously promotes agitation. - In the embodiment illustrated in
FIG. 2 , theanode 52 is a length of 10 gauge insulated copper wire stripped for several inches and rolled into a coil to reduce its overall dimensions. Of course, a copper wire is just one example of a consumable metal source that may be provided as the anode. Other alternatives include a metal mesh structure. Electrical contact between the anode and the component being plated should of course not occur. Therefore, in an exemplary embodiment the anode is inserted into, e.g., a double walledporous bag 54 of non-conductive material to prevent electrical contact but to allow solution access. The anode is connected to a suitable poser supply (a 2-3 V DC power supply was used in a test apparatus). The device itself is electrically coupled to the power supply as a cathode, e.g., viacontact 56. - In the assembly illustrated in
FIG. 2 , the reservoir may be closed remote from the access tube. In the alternative, a recirculating system may be provided wherein the remote end is not closed, but instead the flow is through theclips 30 at each end of the stator bar(s), and the interior of both clips and the respective braze joints are plated simultaneously, as schematically illustrated inFIG. 3 . In the illustrated embodiment, platingsolution reservoirs pump 64 is provided to circulate the plating solution through the clips andbar 16. - Although not illustrated in detail, in practice the device is heated, e.g. with heating tape, to between 40 and 50° C. Heating may also be accomplished with an in-line heater in the electrolyte return tube.
- An exemplary acid copper electroplating solution is a mixture of e.g., water, sulfuric acid, copper sulfate, and a trace of hydrochloric acid. To this mixture a number of organic constituents are added that serve to regulate and distribute the delivery of, e.g., copper to the surface being plated. The two basic organic additives are commonly referred to as the “brightener/leveler” and the “carrier”.
- An electroplating cell is typically comprised of a (non-metallic) container full of the electroplating solution in flow communication with the area or component surface to be treated and a source of plating metal ions, as the anode. In the illustrated embodiment, the electroplating cell is comprised of the component (clip 30)
interior 34, theaccess tubing 40 interior volume, the inflow andoutflow tubes copper wire 52, or other consumable metal source, disposed within theaccess tubing 40 and/orclip 30. This ion supply must be capable of continuous sourcing into a near short circuit load. A typical copper electroplating bath has an effective full load operating “impedance” that ranges from 0.025 Ohms and 0.015 Ohms. The surface for receiving the electroplated coating, referred to as the cathode, in this case the clip, the stator bar, and the braze joint therebetween, is connected to the negative terminal of the current source. Deposition of, e.g., copper in this example, on the target component occurs when an electrical potential is established between the anode and the cathode (target component). The resulting electrical field initiates electrophoretic migration of copper ions from the anode to the electrically conductive surface of the cathode, where the ionic charge is neutralized as the metal ions plate out of solution. As a result, a uniform, thin coating of smooth, bright copper is deposited on the target surface(s). - It should be noted that if it is anticipated that air or evolved gas may become trapped, e.g., in a crevice or a blind recessed area, it will prevent plating in such areas and pressure treatment may be necessary. Pressure treatment may be applied by defining the water pass system as a closed loop that can be sealed and pressurized. Additionally, locating the return flow tube to draw fluid from the vertically upper portion of the stator clip, as mentioned above, facilitates the removal of trapped air or evolved gas to facilitate uniform plating.
- The electroplating process is continued until a deposit layer of about 1 to 3 mm is achieved. The process can be ceased at any time simply by disengaging the power source.
- As an alternative to electroplating a single metal, the plating of the braze joint may be accomplished as a double-layered plating with a first plating followed by a second plating applied over the first plating layer. As will appreciated, a double layered plating provides enhanced durability as compared to a single layered plating particularly where the plating coatings have selective properties; for example, an underlying plated film having strong corrosion resistance and a second plated film applied for air tightness, durability and corrosion resistance.
- As a further alternative, the water pass of the stator bars and/or the clips, for example, may be plated before assembly and then plating can again be carried out after assembly to plate the braze joints, to effectively provide a double layered plating in certain areas or on certain parts.
- In accordance with this invention, all of the joints which have the potential for forming a leakage path are electroplated. In this way, the existing leak or leaks at the stator bar end connections of a generator in the field are repaired. Additionally, by providing a protective coating to all potential leakage paths of the joints, a seal is provided which will ensure against the formation of leakage paths in the future. That is, the electroplating not only isolates the liquid coolant from the brazing material and seals between the joints of adjacent strands and the outermost strands, but can be used to deposit a layer of material over, to seal, the entire interior surface of the coolant flow path, whereby all potential leakage paths are sealed to prevent future leaks. While the present invention is particularly applicable to field repairs of existing generators, it may also be applied to generators during initial manufacture to provide protection against future leakage.
- As noted above, since the method disclosed herein is capable of applying a coating over the entire wetted surface of the flow system, the method can address the clip crevice corrosion leak issue and also other leak issues in liquid cooled generators. For example, the method embodying the invention may used to address clip crack leaks, clip window leaks, plumbing and fitting leaks, and connection ring leaks. Thus, while the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to particulars of the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (11)
1-2. (canceled)
3. An apparatus for electroplating an interior of a component, comprising:
an inflow tube for flowing electroplating solution to an interior of said component;
an outflow tube for flowing electroplating solution out of an interior of said component;
a pump for conducting electroplating solution through said inflow tube and for drawing said electroplating solution through said outflow tube;
an anode disposed in said electroplating solution and electrically connected to a power supply; and
said component being electrically connected to said power supply as a cathode.
4. An apparatus as in claim 3 , further comprising an access tubing coupled to an inlet end of said component for defining an electroplating bath with said interior of said component.
5. An apparatus as in claim 4 , wherein said inflow tube extends through said access tubing.
6. An apparatus as in claim 5 , wherein said outflow tube extends through said access tubing.
7. An apparatus as in claim 3 , further comprising a source of electroplating solution operatively coupled to said pump, said pump drawing electroplating solution from said reservoir and pumping the same through said inflow tube to said component interior.
8. An apparatus as in claim 7 , wherein said pump returns the electroplating solution drawn through said outflow tube to said reservoir.
9. An apparatus as in claim 3 , wherein said anode is formed from at least one of nickel, chromium, zinc and copper.
10. An apparatus as in claim 3 , wherein said anode comprises a consumable metal source.
11. An apparatus as in claim 4 , wherein said anode comprises a length of copper wire that extends through said access tubing.
12-20. (canceled)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/159,344 US20060102469A1 (en) | 2004-11-18 | 2005-06-23 | Electroplating apparatus |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/990,958 US7166941B2 (en) | 2004-11-18 | 2004-11-18 | Electroplated stator bar end and fitting |
US11/159,344 US20060102469A1 (en) | 2004-11-18 | 2005-06-23 | Electroplating apparatus |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/990,958 Division US7166941B2 (en) | 2004-11-18 | 2004-11-18 | Electroplated stator bar end and fitting |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060102469A1 true US20060102469A1 (en) | 2006-05-18 |
Family
ID=36313996
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/990,958 Expired - Fee Related US7166941B2 (en) | 2004-11-18 | 2004-11-18 | Electroplated stator bar end and fitting |
US11/159,337 Abandoned US20060103261A1 (en) | 2004-11-18 | 2005-06-23 | Electroplating method for sealing liquid-cooled generator stator bar structures |
US11/159,344 Abandoned US20060102469A1 (en) | 2004-11-18 | 2005-06-23 | Electroplating apparatus |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/990,958 Expired - Fee Related US7166941B2 (en) | 2004-11-18 | 2004-11-18 | Electroplated stator bar end and fitting |
US11/159,337 Abandoned US20060103261A1 (en) | 2004-11-18 | 2005-06-23 | Electroplating method for sealing liquid-cooled generator stator bar structures |
Country Status (5)
Country | Link |
---|---|
US (3) | US7166941B2 (en) |
JP (1) | JP2006144125A (en) |
CN (1) | CN1783652A (en) |
DE (1) | DE102005054822A1 (en) |
IT (1) | ITMI20052201A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100326820A1 (en) * | 2008-02-25 | 2010-12-30 | Metal Science Technologies Pty Ltd | Electropolishing apparatus |
EP3599703A1 (en) * | 2018-07-25 | 2020-01-29 | Siemens Aktiengesellschaft | Coated conductor for an electro-mechanical device |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7150091B2 (en) * | 2004-11-09 | 2006-12-19 | General Electric Company | Powder coating for generator stator bar end fitting and method for applying the powder coating |
EP2395629A1 (en) * | 2010-06-11 | 2011-12-14 | Siemens Aktiengesellschaft | Stator element |
US9162245B1 (en) * | 2012-03-29 | 2015-10-20 | BTD Wood Powder Coating, Inc. | Powder coating conveyor support |
DE102012022873A1 (en) * | 2012-11-22 | 2014-05-22 | Compact Dynamics Gmbh | Method for soldering stand and cooler and stand with soldered connection to the stand carrier |
CN103595196B (en) * | 2013-11-20 | 2015-12-09 | 哈尔滨电气动力装备有限公司 | Large high-voltage motor bar formula line rod moulding process |
CN104480504A (en) * | 2014-11-20 | 2015-04-01 | 浙江西田机械有限公司 | Vortex wall oxidation device |
US9847702B2 (en) * | 2015-06-08 | 2017-12-19 | General Electric Company | In-situ method for sealing fluid cooled conduits for a generator |
JP2018026977A (en) * | 2016-08-12 | 2018-02-15 | トヨタ自動車株式会社 | Rotary electric machine |
CN106685121B (en) * | 2017-01-16 | 2023-12-05 | 浙江博菲电气股份有限公司 | Flexible plugging sleeve for vertical hydraulic generator stator bar lead insulation box and assembly method thereof |
US10840782B2 (en) | 2017-07-12 | 2020-11-17 | Siemens Energy, Inc. | Assembly and method for connecting ends of generator stator coils with manifold |
JP2019126146A (en) * | 2018-01-15 | 2019-07-25 | 株式会社東芝 | Electroplating apparatus, electrode for electroplating and stator coil assembly method |
CN111593381B (en) * | 2020-05-09 | 2022-04-19 | 西北工业大学 | Anode device for preparing Ni-SiC composite coating on inner wall of hollow part |
Citations (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2503863A (en) * | 1943-11-18 | 1950-04-11 | Siegfried G Bart | Apparatus for electroplating the inside of pipes |
US3614493A (en) * | 1970-01-29 | 1971-10-19 | Gen Electric | Universal liquid-cooled connection assembly |
US3978359A (en) * | 1974-10-30 | 1976-08-31 | Westinghouse Electric Corporation | Coil end insulation for dynamoelectric machines |
US4122870A (en) * | 1976-12-08 | 1978-10-31 | Hines Vernon C | Protective bushing to enclose the end of a conduit liner |
US4199700A (en) * | 1978-07-31 | 1980-04-22 | Westinghouse Electric Corp. | Phase lead for connecting stator coils and parallel phase rings |
US4274021A (en) * | 1976-03-12 | 1981-06-16 | Hitachi, Ltd. | Liquid cooled stator winding for a rotary electric machine having reduced thermal elongation stresses |
US4305792A (en) * | 1977-12-21 | 1981-12-15 | Bristol Aerojet Limited | Processes for the electrodeposition of composite coatings |
US4806807A (en) * | 1987-01-09 | 1989-02-21 | Westinghouse Electric Corp. | Method and apparatus for bolted series/phase generator connections |
US4912831A (en) * | 1987-01-09 | 1990-04-03 | Westinghouse Electric Corp. | Method for assembling bolted stator coils |
US4982122A (en) * | 1988-05-23 | 1991-01-01 | Westinghouse Electric Corp. | Method and apparatus for insulating liquid-cooled stator coil headers and connectors |
US5304877A (en) * | 1991-03-20 | 1994-04-19 | Gold Star Co., Ltd. | Rotor of a canned motor for a canned motor pump |
US5316801A (en) * | 1992-11-25 | 1994-05-31 | General Electric Company | Electrostatic powder coating method for insulating the series loop connections of a dynamoelectric machine |
US5423473A (en) * | 1994-05-09 | 1995-06-13 | Westinghouse Electric Corporation | Device for installing a header cap on a water header of a stator coil |
US5496463A (en) * | 1993-12-08 | 1996-03-05 | Nihon Parkerizing Co., Ltd. | Process and apparatus for composite electroplating a metallic material |
US5557837A (en) * | 1995-01-26 | 1996-09-24 | Abb Management Ag | Method for repairing stator winding bars |
US5581869A (en) * | 1995-08-15 | 1996-12-10 | General Electric Co. | Repair method for sealing liquid-cooled stator bar end fittings for a generator |
US5605590A (en) * | 1995-05-22 | 1997-02-25 | General Electric Co. | Methods for sealing liquid-cooled stator bar end connections for a generator |
US5659944A (en) * | 1995-01-26 | 1997-08-26 | Asea Brown Boveri Ag | Method for repairing a connecting device for the electrical connection and for supplying and carrying away the coolant to and from the hollow conductor elements of the stator winding bars of electrical machines |
US6031751A (en) * | 1998-01-20 | 2000-02-29 | Reliance Electric Industrial Company | Small volume heat sink/electronic assembly |
US6124659A (en) * | 1999-08-20 | 2000-09-26 | Siemens Westinghouse Power Corporation | Stator wedge having abrasion-resistant edge and methods of forming same |
US6276726B1 (en) * | 1999-09-03 | 2001-08-21 | Ronald A. Daspit | Pipe line repair anti-corrosion electrically isolated clamp-coupling |
US20010040090A1 (en) * | 2000-01-19 | 2001-11-15 | Tetsuya Kuroda | Plating pretreatment apparatus and plating treatment apparatus |
US6477167B1 (en) * | 1999-06-03 | 2002-11-05 | Fujitsu Network Communications, Inc. | Method and system for allocating bandwith to real-time variable bit rate (rt-VBR) traffic |
US20030065242A1 (en) * | 2001-08-13 | 2003-04-03 | Ludger Dinkelborg | Radioactive implantable devices and methods and apparatuses for their production and use |
US6778053B1 (en) * | 2000-04-19 | 2004-08-17 | General Electric Company | Powder coated generator field coils and related method |
US6800971B1 (en) * | 1999-06-01 | 2004-10-05 | Robert Bosch Gmbh | Starter generator for an internal combustion engine and method of producing same |
US20050012408A1 (en) * | 2003-07-18 | 2005-01-20 | Kim Young Jin | Application of corrosion protective coating for extending the lifetime of water cooled stator bar clips |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3922396A (en) * | 1974-04-23 | 1975-11-25 | Chromalloy American Corp | Corrosion resistant coating system for ferrous metal articles having brazed joints |
US4294670A (en) * | 1979-10-29 | 1981-10-13 | Raymond Louis W | Precision electroplating of metal objects |
GB2230537B (en) * | 1989-03-28 | 1993-12-08 | Usui Kokusai Sangyo Kk | Heat and corrosion resistant plating |
JPH06240499A (en) * | 1993-02-12 | 1994-08-30 | Yamaha Corp | Plating method and apparatus |
US5895561A (en) * | 1996-01-17 | 1999-04-20 | Kennecott Utah Copper Corporation | Method of sealing cooling blocks using electrodeposited metal |
US5875539A (en) | 1996-11-14 | 1999-03-02 | Siemens Westinghouse Power Corporation | Water-cooled stator coil end sealing process |
KR100390890B1 (en) | 1998-11-14 | 2003-10-08 | 주식회사 하이닉스반도체 | A method for forming a conductive layer and an apparatus thereof |
JP2001200838A (en) | 1999-11-09 | 2001-07-27 | Seiko Instruments Inc | Fluid dynamic pressure bearing, fluid dynamic pressure bearing device, manufacturing method of fluid dynamic pressure bearing, and bearing surface machining method |
-
2004
- 2004-11-18 US US10/990,958 patent/US7166941B2/en not_active Expired - Fee Related
-
2005
- 2005-06-23 US US11/159,337 patent/US20060103261A1/en not_active Abandoned
- 2005-06-23 US US11/159,344 patent/US20060102469A1/en not_active Abandoned
- 2005-11-04 JP JP2005320294A patent/JP2006144125A/en not_active Withdrawn
- 2005-11-15 DE DE102005054822A patent/DE102005054822A1/en not_active Withdrawn
- 2005-11-17 IT IT002201A patent/ITMI20052201A1/en unknown
- 2005-11-18 CN CNA2005100230343A patent/CN1783652A/en active Pending
Patent Citations (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2503863A (en) * | 1943-11-18 | 1950-04-11 | Siegfried G Bart | Apparatus for electroplating the inside of pipes |
US3614493A (en) * | 1970-01-29 | 1971-10-19 | Gen Electric | Universal liquid-cooled connection assembly |
US3978359A (en) * | 1974-10-30 | 1976-08-31 | Westinghouse Electric Corporation | Coil end insulation for dynamoelectric machines |
US4274021A (en) * | 1976-03-12 | 1981-06-16 | Hitachi, Ltd. | Liquid cooled stator winding for a rotary electric machine having reduced thermal elongation stresses |
US4122870A (en) * | 1976-12-08 | 1978-10-31 | Hines Vernon C | Protective bushing to enclose the end of a conduit liner |
US4305792A (en) * | 1977-12-21 | 1981-12-15 | Bristol Aerojet Limited | Processes for the electrodeposition of composite coatings |
US4199700A (en) * | 1978-07-31 | 1980-04-22 | Westinghouse Electric Corp. | Phase lead for connecting stator coils and parallel phase rings |
US4806807A (en) * | 1987-01-09 | 1989-02-21 | Westinghouse Electric Corp. | Method and apparatus for bolted series/phase generator connections |
US4912831A (en) * | 1987-01-09 | 1990-04-03 | Westinghouse Electric Corp. | Method for assembling bolted stator coils |
US4982122A (en) * | 1988-05-23 | 1991-01-01 | Westinghouse Electric Corp. | Method and apparatus for insulating liquid-cooled stator coil headers and connectors |
US5304877A (en) * | 1991-03-20 | 1994-04-19 | Gold Star Co., Ltd. | Rotor of a canned motor for a canned motor pump |
US5316801A (en) * | 1992-11-25 | 1994-05-31 | General Electric Company | Electrostatic powder coating method for insulating the series loop connections of a dynamoelectric machine |
US5496463A (en) * | 1993-12-08 | 1996-03-05 | Nihon Parkerizing Co., Ltd. | Process and apparatus for composite electroplating a metallic material |
US5528827A (en) * | 1994-05-09 | 1996-06-25 | Westinghouse Electric Corporation | Method and device for installing a header cap on a water header of a stator coil |
US5423473A (en) * | 1994-05-09 | 1995-06-13 | Westinghouse Electric Corporation | Device for installing a header cap on a water header of a stator coil |
US5557837A (en) * | 1995-01-26 | 1996-09-24 | Abb Management Ag | Method for repairing stator winding bars |
US5659944A (en) * | 1995-01-26 | 1997-08-26 | Asea Brown Boveri Ag | Method for repairing a connecting device for the electrical connection and for supplying and carrying away the coolant to and from the hollow conductor elements of the stator winding bars of electrical machines |
US5605590A (en) * | 1995-05-22 | 1997-02-25 | General Electric Co. | Methods for sealing liquid-cooled stator bar end connections for a generator |
US5581869A (en) * | 1995-08-15 | 1996-12-10 | General Electric Co. | Repair method for sealing liquid-cooled stator bar end fittings for a generator |
US6031751A (en) * | 1998-01-20 | 2000-02-29 | Reliance Electric Industrial Company | Small volume heat sink/electronic assembly |
US6800971B1 (en) * | 1999-06-01 | 2004-10-05 | Robert Bosch Gmbh | Starter generator for an internal combustion engine and method of producing same |
US6477167B1 (en) * | 1999-06-03 | 2002-11-05 | Fujitsu Network Communications, Inc. | Method and system for allocating bandwith to real-time variable bit rate (rt-VBR) traffic |
US6124659A (en) * | 1999-08-20 | 2000-09-26 | Siemens Westinghouse Power Corporation | Stator wedge having abrasion-resistant edge and methods of forming same |
US6276726B1 (en) * | 1999-09-03 | 2001-08-21 | Ronald A. Daspit | Pipe line repair anti-corrosion electrically isolated clamp-coupling |
US20010040090A1 (en) * | 2000-01-19 | 2001-11-15 | Tetsuya Kuroda | Plating pretreatment apparatus and plating treatment apparatus |
US6778053B1 (en) * | 2000-04-19 | 2004-08-17 | General Electric Company | Powder coated generator field coils and related method |
US20030065242A1 (en) * | 2001-08-13 | 2003-04-03 | Ludger Dinkelborg | Radioactive implantable devices and methods and apparatuses for their production and use |
US20050012408A1 (en) * | 2003-07-18 | 2005-01-20 | Kim Young Jin | Application of corrosion protective coating for extending the lifetime of water cooled stator bar clips |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100326820A1 (en) * | 2008-02-25 | 2010-12-30 | Metal Science Technologies Pty Ltd | Electropolishing apparatus |
EP3599703A1 (en) * | 2018-07-25 | 2020-01-29 | Siemens Aktiengesellschaft | Coated conductor for an electro-mechanical device |
WO2020021025A1 (en) * | 2018-07-25 | 2020-01-30 | Siemens Aktiengesellschaft | Coated article for an electro-mechanical device |
US11804747B2 (en) | 2018-07-25 | 2023-10-31 | Siemens Energy Global GmbH & Co. KG | Coated article for an electro-mechanical device |
Also Published As
Publication number | Publication date |
---|---|
US7166941B2 (en) | 2007-01-23 |
DE102005054822A1 (en) | 2006-05-24 |
US20060103261A1 (en) | 2006-05-18 |
JP2006144125A (en) | 2006-06-08 |
ITMI20052201A1 (en) | 2006-05-19 |
CN1783652A (en) | 2006-06-07 |
US20060103244A1 (en) | 2006-05-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20060102469A1 (en) | Electroplating apparatus | |
US7202579B2 (en) | Corrosion protective coating for extending the lifetime of water cooled stator bar clips | |
EP1622245B1 (en) | Metallic barrier coating for generator stator bar end fitting and method for applying the coating | |
US5581869A (en) | Repair method for sealing liquid-cooled stator bar end fittings for a generator | |
JP2006230183A (en) | Powder-coating film for coating stator bar end part fitting of generator, and method for coating the powder-coating film | |
US5605590A (en) | Methods for sealing liquid-cooled stator bar end connections for a generator | |
KR20000053286A (en) | Water-cooled stator coil end seaing process | |
EP1652962A1 (en) | Electroless metallic plating method for leak repair and prevention in liquid-cooled generator stator bars | |
US3697405A (en) | Apparatus for partial electroplating including an electroplating head | |
KR20090005322A (en) | Hollow electrode with film for electrodeposition coating | |
CN206775348U (en) | Immerse device | |
JP2022118256A (en) | Substrate holder, plating device, plating method, and memory medium | |
US20050227009A1 (en) | Epoxy spray lining for liquid-cooled generator stator bar clips | |
JP2010071557A (en) | Heat exchanger for fuel cell and method for manufacturing the same | |
KR100843952B1 (en) | Apparatus for electroforming inside of tube having integrated air and electroforming solution supplying device | |
US20220065563A1 (en) | Methods of anodizing the internal surface of heat transfer tubes | |
CN107294045B (en) | High-voltage cable joint structure and high-tension cable immersion connection method | |
JPS6320499A (en) | Plating device for pipe inside | |
EP1700015A1 (en) | Well cooler | |
CN116695208A (en) | Water-cooling plate processing method for preventing crystallization after cooling liquid is introduced into water-cooling plate | |
Niewodniczanski et al. | Mechanical Design Features of the Unilac | |
JPS6369997A (en) | Apparatus for plating inside of tube | |
JPS62247098A (en) | Method for plating inside of tube | |
JPS61230270A (en) | Fuel cell | |
JPH05117881A (en) | Electrolyzer for generating iron ion and method for preventing corrosion thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |