Annulus pressure operated downhole choke and associated methods
US5992520A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Sep 15, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A downhole choke and associated methods provide enhanced efficiency and accuracy in well sampling and testing operations due to its capability for substantially minimizing the amount of time needed to establish steady state flow conditions in a well, and the ability to sample fluids downhole at varying downhole flow restrictions. In a described embodiment, a downhole choke is operable to restrict fluid flow therethrough by applying a predetermined fluid pressure to an annulus formed between the choke and the wellbore. The downhole choke has an axial flow passage formed therethrough, a portion of which has interchangeable flow areas. The flow areas are interchanged upon application of the predetermined fluid pressure, and again interchanged upon expiration of a time delay. One of the flow areas permits substantially unrestricted fluid flow therethrough, and another of the flow areas permits restricted flow therethrough.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.