Application of corrosion protective coating for extending the lifetime of water cooled stator bar clips
US6969932B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 18, 2003 |
| Grant date | Nov 29, 2005 |
| Priority date | — |
| Expiry date | Oct 10, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49009
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A water-cooled stator bar clip for electrical generators and a method for applying a corrosion-resistant protective coating, preferably Sc, Ti, Cr, Zr, Nb, Mo, Hf, Ta, W, Ni, and Al, and their alloys or oxides to existing stator bar end fittings in order to significantly reduce the possibility of leaks through the brazed connections of the copper stator bar end connections. The coatings can be applied locally using various known physical vapor deposition (“PVD”), chemical vapor deposition (“CVD”) or other direct coating techniques known in the art. For example, the coatings can be applied using ion plasma deposition, sputtering or wire arc techniques (all PVD processes) or by using electroplating, high velocity oxygen free (“HVOF”) deposition, DC arc or electroless plating. Preferably, the coatings are applied either to new stator bar clips or to existing clips in the field using a known pencil coater technique. After being deposited, the metallic coatings form a protective oxide layers over the existing copper brazed joint after being exposed to a water environment, thereby protecting the chemical and structural integrity of the underlying copper brazed joint.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.