| Abstract |
The extreme downhole conditions in a geothermal well combine to make it one of the most challenging design environments encountered by modern technology. Complicating the design of logging tools and other hardware intended for deployment in geothermal wells are the high temperatures, high pressures, shock and vibration, corrosive fluids, inaccessibility, difficulty in testing, and even a limited ability to communicate and know what is actually going on downhole. This paper describes the design parameters that must be considered when developing a downhole tool for geothermal wells. These parameters can be grouped into several categories related to the integrated design process of the tool: 1) design of the measurement method and technique, to ensure that the data that will be obtained is of the type and quality needed for well or resource evaluation; 2) design of the electronic circuits and components to provide whatever level of downhole data acquisition, processing, storage, and telemetry is needed; and 3) design of the mechanical packaging to carry the transducers and electronics and provide whatever level of protection is necessary against high temperatures, high pressures, shock, vibration, and corrosion. |