System for calculating formation temperatures
US4575261A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1983 |
| Grant date | Mar 11, 1986 |
| Priority date | — |
| Expiry date | Jun 30, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K3/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Determination of drilling mud thermal conductivity for estimation of earth formation temperature through a well bore thermal model. Borehole annulus and drill pipe bore temperature measurements are taken over a relatively short period of time when circulation of drilling mud is interrupted and temperature differentials maximized. The dynamic temperature response characteristics related to the heat transfer and storage parameters of the drill pipe, mud and bit are integrated into a mathematical borehole model incorporating the thermal resistance, heat capacity, and heat generation of the mud and drill pipe and the drill bit. The maximum temperature differential is then determined and the response characteristics used to establish the requisite parameters for the thermal conductivity and temperature calculations. In this manner, formation temperatures can be estimated to monitor downhole mud behaviour and geothermal gradients.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.