Drilling and completion muds useful at elevated temperatures
US4536296A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1983 |
| Grant date | Aug 20, 1985 |
| Priority date | — |
| Expiry date | Mar 10, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/24
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention is clay based water drilling or completion muds with low viscosity and exceptional stability at elevated temperatures of up to 200.degree. C. The muds are characterized by containing from 1 to 10 grams per liter of a low molecular weight polymer or copolymer having functional groups wherein from 2 to 95% of the functional groups consist independently of hydroxamic or thiohydroxamic groups. The mud composition comprises (a) fresh water, water containing electrolytes such as sodium chloride, potassium chloride, calcium chloride, magnesium chloride, or seawater; (b) clay, chosen to suit the saline concentration of the water and to provide the necessary properties; and (c) one or more viscosity increasing materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.