Method of downlinking to a downhole tool
US8196678B2 · kind B2 · utility
10Cited by
2References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 18, 2009 |
| Grant date | Jun 12, 2012 |
| Priority date | — |
| Expiry date | Jun 22, 2030 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/08
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method of downlinking to a downhole tool located in a borehole is provided. The downhole tool detects transitions in the flow velocity of fluid circulating in the borehole at the downhole tool. To provide for the detection of the transitions fluid is pumped into the drillstring so that it circulates in the borehole at the downhole tool and the the pumping rate of fluid into the drillstring is either increased to a rate which overshoots a steady state pumping rate needed to produce a transition or is decreased to a rate which undershoots a steady state pumping rate needed to produce a transition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.