Logging method and apparatus using a sonde equipped with measuring pads
US5022484A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1986 |
| Grant date | Jun 11, 1991 |
| Priority date | — |
| Expiry date | May 16, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S367/911
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Method and apparatus for applying the measuring pads of a logging sonde against the walls of a borehole. Dip measurements and geological investigation of earth formations traversed by a deviated borehole require that the measuring pads be pressed against the borehole walls by means of articulated arms which maintain the pads symmetrical and parallel with respect to the sonde. In the preferred embodiment, two independent resilient forces are applied to the pads. The first resilient force is substantially constant at all extensions of the arms in the borehole, while the second resilient force is adjustable to suit local parameters. The second resilient force is preferably adjustable from surface instrumentation while the sonde is making measurements in the borehole. The first resilient force is provided by independent leaf springs acting on each of the pads, while the second resilient force is preferably provided by a coil spring acting on each of the pairs of opposing arms. A flexible joint may be used between the cartridge and sonde sections of the logging tool to reduce the total weight bearing down upon the pads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.