Method and system for testing a borehole by the use of a movable plug
US6631763B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 2002 |
| Grant date | Oct 14, 2003 |
| Priority date | — |
| Expiry date | Feb 5, 2022 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/129
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method and a system for testing a borehole in an underground formation by the use of so-called closed chamber testing. When carrying out the method, a test or production pipe (5) is carried down the borehole, where the test pipe can be closed at its upper end and at its lower end is provided with a downhole assembly (6) comprising equipment for testing of fluid flow from the formation (3), the annulus (23) between the test pipe (5) and a casing (20) in the borehole being shut off during the test by a gasket (22) at a desired depth, and fluid from the formation being allowed to flow through the test pipe (5) to a collecting tank (9) coupled to the test pipe via a flow head (4) at the upper end of the test pipe (5). In the downhole assembly (6) at the lower end of the test pipe (5) there is releasably retained a pig (30) forming a barrier between formation fluid and a lightweight damping fluid (7) filling the test pipe above the pig, the pig (30) being released at the start of the test and being moved in a controlled manner upwards in the pipe (5) as a result of a positive pressure difference between the fluids below and above the pig.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.