Apparatus and method for measuring formation pressure using a nozzle
US6769296B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2002 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Mar 28, 2022 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for measuring a downhole formation pressure is disclosed which includes lowering a formation testing tool to a desired measuring position in a well borehole. Then a nozzle in the tool is extended so that the nozzle extends through the mud cake layer on a surface of a formation, forming a seal between the mud cake layer and a sealing surface of the nozzle. In an embodiment of the invention, the nozzle has a porous tip that extends into the invaded zone beyond the mudcake layer and is exposed to the formation pressure. In an alternate embodiment, the nozzle has a retractable tip that retracts into the nozzle. The nozzle and retractable tip are positioned in the mudcake and the retractable tip is retracted into the nozzle. The formation pressure is then communicated through the nozzle to a pressure sensor operatively connected to the nozzle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.