Method for controlling lost circulation of drilling fluids with water absorbent polymers
US4635726A · kind A · utility
41Cited by
26References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 28, 1985 |
| Grant date | Jan 13, 1987 |
| Priority date | — |
| Expiry date | May 28, 2005 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/003
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The invention is a method for reducing lost circulation of aqueous or oil based drilling fluids wherein one or more water absorbent polymers are dispersed in a hydrocarbon fluid which is injected into the lost circulation zone. The hydrocarbon carrier fluid initially prevents water from contacting the water absorbent polymer until such water contact is desired. Once the hydrocarbon slug containing the polymer is properly placed at the lost circulation zone, water is mixed with the hydrocarbon slug so that the polymer will expand with the absorbed water and substantially increase in size to close off the lost circulation zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.