Water based drilling fluid additive and methods of using fluids containing additives
US5652200A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 1995 |
| Grant date | Jul 29, 1997 |
| Priority date | — |
| Expiry date | Aug 24, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/94
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An additive for a water-based fluid which is to be used when the likelihood of differential sticking is high and which reduces the sticking tendency of the fluid and mud cake. An additive according to the invention comprises a well dispersed-particulate phase such as an emulsion, a fine emulsion, a microemulsion, a micellar phase or a polymeric phase having a particle size comparable with the pore throat size of a mud cake and comprising a material which forms easily deformable particles and which reduces the sticking propensity of the mud. One embodiment of the invention comprises a microemulsion of an oil which is well dispersed, substantially stable and has a substantial portion of the particle size distribution in the range 5-500 nm. An alternative embodiment comprises a micellar phase comprising one or more surfactants. The additive is typically used at a level of about 5% by volume in the drilling fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.