Temperature and Pressure Logging Tools Using No Down-Hole Electronics
- Key words
- Well Logging; USA; Nevada; Los Alamos; Fenton Hill; 275 C; Temperature; Digital Voltmeter; Field Test; US DOE; LANL; S-Cubed; Southwest Research Institute
- Conference
- Geothermal Resources Council Transactions
- Year
- 1979
- Session
- Well logging; High temperature reservoirs; Temperature gradi
- Language
- English
Abstract
A geothermal sonde for measuring temperature and pressure using no downhole electronics was designed and tested for operation at temperature up to 275°C (527°F) and pressures of at least 10,000 psi. The measurement system uses variable resistance transducers which are powered in series by an uphole constant current supply. The output signals from the transducers are measured with a digital voltmeter having very high common mode and normal mode rejection ratios. The high rejection ratios of the digital voltmeter virtually eliminate any noise or pickup introduced into the measurement system. The system was tested in a hydroclave at temperatures up to 288°C (550°F) and at pressures up to 8,000 psi. The sonde was also tested at Los Alamos geothermal well at temperatures up to 186°C (366°F) and pressures up to 4100 psi.
Copyright 1979, Geothermal Resources Council. Readers who download papers from this site should honour the copyright of the original authors, and may not copy or distribute the work further without the permission of the original publisher.