Invert emulsion drilling fluid comprising oligamide composition
US4663076A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1985 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Jun 26, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S516/07
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a surfactant for use in invert emulsion drilling fluids, the invert emulsion drilling fluid produced therefrom, and a method of drilling, completing and working over a subterranean well utilizing said drilling fluid. The drilling fluid comprises an emulsion formed by producing a diamide having from between about 20 mole percent and about 35 mole percent of a polyamine, and from between about 30 mole percent and about 70 mole percent of a fatty acid having from between about 6 to about 20 carbon atoms therein, the diamide thereafter being further reacted with from between about 15 mole percent and about 35 mole percent of a tricarboxylic acid. The total amine value of said oligamide being from between about 10 to about 30, and the acid value of said oligamide being from between about 26 to about 46. When the surfactant is diluted to about 70 w/w percent concentration with a suitable solvent, the ES.sub.3, as defined herein, of said emulsion drilling fluid will exceed about 400 volts, the ES.sub.5, as defined herein, will be greater than the ES.sub.4, and the ES.sub.5 will be greater than about 1,000 volts. Alternatively, the electrical stability of t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.