Double-walled tube with interface gap and production method therefor
US9153348B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 2011 |
| Grant date | Oct 6, 2015 |
| Priority date | — |
| Expiry date | Jun 17, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49927
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
After an inner wall tube, made of steel or alloy containing not less than 2% of Cr, whose outer surface thereof is machined and/or ground to a thickness of 0.1 mm or more including the scale layer, is inserted into an outer wall tube, made of ferritic steel containing not less than 2% of Cr, in which an oxide scale layer containing Cr and having a thickness of 10 to 30 μm is formed in the inner surface thereof, cold working at an outside diameter reduction rate of 5 to 30% is performed. Similarly cold worked after an inner wall tube having an oxide scale layer on the outer surface thereof, is inserted into an outer wall tube whose inner surface is machined and ground. A double-walled tube made has a uniform gap and an excellent thermal conductivity, and is suitable as materials for SG tubes of future FBR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.