Welded corrosion-resistant ferritic stainless steel tubing having high resistance to hydrogen embrittlement and a cathodically protected heat exchanger containing the same
US4942922A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1988 |
| Grant date | Jul 24, 1990 |
| Priority date | — |
| Expiry date | Oct 18, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S165/905
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Welded ferritic stainless steel tubing having high resistance to hydrogen embrittlement particularly adapted for use in heat exchangers handling chemical media containing hydrogen sulfide or nascent hydrogen and in cathodically protected heat exchangers. The ferritic stainless steel of the welded tubing consists essentially of, in weight percent, carbon at least 0.002, nitrogen at least 0.002, carbon plus nitrogen 0.02 max. and preferably 0.01 to 0.02, chromium 23 to 28, preferably 25 to 28, manganese up to 1, preferably up to 0.5, nickel 1 to 4, silicon up to 1, preferably up to 0.5, phosphorus up to 0.04, sulfur up to 0.02, preferably up to 0.005, molybdenum 2 to 5, preferably 2 to 4, aluminum up to 0.1, columbium 0.60 max. with columbium being at least equal to eight times carbon plus nitrogen, and the balance iron and incidental impurities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.