Stock material or miscellaneous articles – All metal or with adjacent metals – Composite; i.e. – plural – adjacent – spatially distinct metal...
Reexamination Certificate
2001-06-05
2003-12-30
Zimmerman, John J. (Department: 1775)
Stock material or miscellaneous articles
All metal or with adjacent metals
Composite; i.e., plural, adjacent, spatially distinct metal...
C428S633000, C428S651000, C428S655000, C428S660000, C148S240000, C148S281000, C148S528000
Reexamination Certificate
active
06670050
ABSTRACT:
BACKGROUND
The invention relates to heat exchangers. More specifically, the invention relates to oxidation protection of titanium-based heat exchangers.
Certain heat exchangers used in aircraft environmental control systems are exposed to temperatures exceeding 400° C. These heat exchangers are typically made of stainless steel, which can withstand the high temperatures.
It would be desirable to use titanium heat exchangers instead of stainless steel heat exchangers. Titanium and its alloys have a light weight and can provide a weight reduction of up to 40% over comparable stainless steel heat exchangers. The weight reduction results in better fuel efficiency and lower aircraft operating costs.
However, titanium is not used for high temperature heat exchanger applications because the titanium exhibits a propensity to rapidly oxidize, (over a couple of hours), at the required operating temperatures. Oxidation of titanium results in a reduction in ductility and then strength, and a deterioration in structural integrity. Repeated thermal cycling at temperatures between ambient temperature and around 400° C. (and higher) causes the titanium to crack. Cross contamination of fluids can occur and lead to life-threatening conditions.
REFERENCES:
patent: 4681818 (1987-07-01), Unnam et al.
patent: 4936927 (1990-06-01), Grunke et al.
patent: 5110035 (1992-05-01), Reynolds et al.
patent: 5267605 (1993-12-01), Doty et al.
patent: 5564496 (1996-10-01), Blum et al.
patent: 5585136 (1996-12-01), Barrow et al.
patent: 5673436 (1997-10-01), Piper
patent: 0 495 454 (1992-07-01), None
patent: 0 518 590 (1992-12-01), None
patent: 0 671 240 (1995-09-01), None
patent: 2 252 981 (1992-08-01), None
patent: 2-85694 (1990-03-01), None
patent: WO 98/54531 (1998-12-01), None
Chipko Paul
Pohlman Matthew J.
Raybould Derek
Caglar Esq. Oral
Honeywell International , Inc.
Savage Jason
Zimmerman John J.
LandOfFree
Titanium-based heat exchangers and methods of manufacture does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Titanium-based heat exchangers and methods of manufacture, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Titanium-based heat exchangers and methods of manufacture will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3111700