Powder coating for generator stator bar end fitting and method for applying the powder coating

• US 20070051779A1
• Filed: 11/09/2006
• Published: 03/08/2007
• Est. Priority Date: 11/09/2004
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Wang, Yu, Lusted, Roderick, Mall, Waheed
• Granted Patent: US 7,417,341 B2
• Time in Patent Office: Days
• US Class Current: 228/101
• CPC Class Codes: H02K 15/0093 Manufacturing or repairing cooling fluid boxes, i.e. terminals of fluid cooled windings ensuring both electrical and fluid connection
• CPC Class Codes: H02K 15/12 Impregnating, heating or drying of windings, stators, rotors or machines
• CPC Class Codes: H02K 3/44 Protection against moisture or chemical attack; Windings specially adapted for operation in liquid or gas
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine

Abstract

A method of sealing a generator stator bar and a stator bar end fitting receiving the end including the steps of: brazing the fitting to the end of the stator bar with a braze material; applying a powder coating material to the end of the stator bar in the fitting; and curing the powder coating material to form a barrier coating on the end of the stator bar and the adjoining interior surfaces of the fitting.

Claims

1. An assembly comprising a 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 chamber has a polymer layer powder coated and cured on a surface thereof.

2. An assembly as in claim 1, wherein said polymer layer extends substantially continuously over a junction of said fitting and said stator bar end.

3. An assembly as in claim 1, wherein said polymer comprises a thermosetting epoxy.

4. An assembly as in claim 1, wherein the polymer layer has a thickness of about 0.002 to about 0.050 inches.

5. An assembly as in claim 14, wherein the polymer layer has a thickness of about 0.018 to about 0.020 inches.

6. A fitting for a stator bar of a generator comprising:

a fitting housing having a collar at a first end and a cooling fluid coupling at an opposite end, wherein said collar is configured to be brazed to an end of the stator bar;

a chamber extending from the first end to the opposite end of the fitting; and

a polymer coating on an end of the stator bar in said chamber and forming a seal between the end and a remaining portion of the chamber.

7. A fitting as in claim 6, wherein said polymer layer extends substantially continuously over a junction of said fitting and said stator bar end.

8. A fitting as in claim 6, wherein said polymer comprises a thermosetting epoxy.

9. A fitting as in claim 6, wherein the polymer layer has a thickness of about 0.002 to about 0.050 inches.

10. A fitting as in claim 9, wherein the polymer layer has a thickness of about 0.018 to about 0.020 inches.