Stock material or miscellaneous articles – All metal or with adjacent metals – Composite; i.e. – plural – adjacent – spatially distinct metal...
Reexamination Certificate
2008-07-08
2008-07-08
La Villa, Michael (Department: 1794)
Stock material or miscellaneous articles
All metal or with adjacent metals
Composite; i.e., plural, adjacent, spatially distinct metal...
C428S336000, C428S469000, C428S472100, C428S666000, C138S140000, C138S141000
Reexamination Certificate
active
07396597
ABSTRACT:
A stainless steel pipe includes a base metal containing 20-35 mass % of Cr, and a Cr-depleted zone is formed in the surface region of the pipe. The Cr concentration in the Cr-depleted zone is at least 10%, and the thickness of the Cr-depleted zone is at most 20 micrometers. A Cr-based oxide scale layer having a Cr content of at least 50% and a thickness of 0.1-15 micrometers may be provided on the outer side of the Cr-depleted zone. An Si-based oxide scale layer with an Si content of at least 50% may be provided between the Cr-based oxide scale layer and the Cr-depleted zone. The pipe is particularly suitable for use in petroleum refineries or petrochemical plants, such as for use as a pipe of a cracking furnace of an ethylene plant.
REFERENCES:
patent: 3904378 (1975-09-01), Higbee et al.
patent: 4472223 (1984-09-01), Bowsky
patent: 5804056 (1998-09-01), Pempera et al.
patent: 6503347 (2003-01-01), Wysiekierski et al.
patent: 2233672 (1991-01-01), None
patent: 53-66832 (1978-06-01), None
patent: 53-66835 (1978-06-01), None
patent: 57-023050 (1982-02-01), None
patent: 57-043989 (1982-03-01), None
patent: 02-008336 (1990-01-01), None
patent: 09291342 (1997-11-01), None
patent: 11-029776 (1999-02-01), None
patent: 2000-509105 (2000-07-01), None
Database WPI, Section Ch, Week 200217, Derwent Publications, Ltd., London, GB, Class M24, AN 2002-128805, XP002307674, no date.
Database WPI, Section Ch, Week 200378, Derwent Publications, Ltd., London, GB, Class M24, AN 2003-840606, XP002307675, no date.
“The Relation between Carburization Resistance and Surface Oxide Film of Heat Resistant Steels for Petro-chemical Plants” by Kunihiko Yoshikawa, et al.;The Sumitomo Search, No. 33, Nov. 1986.
Nishiyama Yoshitaka
Yamadera Yoshimi
Clark & Brody
La Villa Michael
Sumitomo Metal Industries Ltd.
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