Method and apparatus for determining a depth correction for a logging tool in a well
US5522260A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1994 |
| Grant date | Jun 4, 1996 |
| Priority date | — |
| Expiry date | Apr 7, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V11/002
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of determining a depth correction for a logging tool that is moved, while suspended from a cable, along a well, the method being of the type in which a measurement of tool depth is performed at the surface at successive instants, the tool comprising at least two sensors suitable for measuring a characteristic of the well at each instant said two sensors being offset longitudinally in the displacement direction of the tool. The method comprises, at each of said instants: PA1 determining a first value for tool velocity by intrinsic measurement; PA1 determining a second value of the velocity by correlation between information received from the two sensors; and PA1 combining the first and second velocity values to determine a depth correction to be applied to the surface depth measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.