Repair of microannuli and cement sheath
US5127473A · kind A · utility
204Cited by
37References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 8, 1991 |
| Grant date | Jul 7, 1992 |
| Priority date | — |
| Expiry date | Jan 8, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2111/72
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a method of repairing holes, channels, voids and microannuli in a cement sheath situated in the annular space between a casing and the wall of a wellbore penetrating a subterranean earth formation, which method involves the use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement, which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.