Method and apparatus for relaying downhole data to the surface
US5294923A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1992 |
| Grant date | Mar 15, 1994 |
| Priority date | — |
| Expiry date | Jan 31, 2012 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/085
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus and method for the transmission of information between downhole and surface locations through a drillstring. The apparatus includes a wireline extending from instrumentation at the downhole location to a clamp-off sub in the drillstring where it is connected to the lower end of a cable spooled on a cable cartridge above the clamp-off sub in the drillstring. The cable cartridge is moved upwardly through successive pipe joints added to the drillstring as drilling progresses, to permit rotation of the drillstring and use of blowout preventors without retrieving the wireline or cable. Cartridge cable is releasably connected at its upper end to a wireline extending through a pack-off to a slip ring assembly at the surface, for transmitting data from downhole instrumentation to surface equipment. Multiple cable cartridges may be sequentially added in series if drilling proceeds beyond the length of cable in a single cartridge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.