Process and plug for well abandonment
US5667010A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1995 |
| Grant date | Sep 16, 1997 |
| Priority date | — |
| Expiry date | Mar 21, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/134
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A plug and process for use in well abandonment is taught. The plug includes a retaining structure, such as a cement plug, which is placed in the well borehole and an amount of a viscous substance, such as sand and fines in bitumen, above the retaining structure. The viscous substance prevents the passage of fluids vertically through the well borehole. The plug remains viscous over time and can flow to fill void which may open up in the well adjacent the plug. To enhance the sealing characteristics of the plug, the process for placement of the plug includes the removal of a section of the well casing and possibly also the sheath and a layer of the borehole wall behind the removed section of the casing at the position of the plug to prevent the flow of fluids around the plug.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.