Strength retrogression preventer
US7448449B2 · kind B2 · utility
7Cited by
10References
28Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2005 |
| Grant date | Nov 11, 2008 |
| Priority date | — |
| Expiry date | Aug 19, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/91
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Cementitious slurries capable of controlling and/or preventing strength retrogression during the cementing of a formation contain a bismuth salt or derivative thereof. Bismuth trioxide is preferred. The cementitious slurry may further contain a density modifying agent and/or strength enhancer. The cementitious slurries of the invention are suitable for use over a broad temperature range of from about 45° F. to about 500° F.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.