Prototype data logger for oil wells
Around 2000, TNO-FEL developed a prototype data acquisition system for Shell in collaboration with TU Delft and Fraunhofer IMS. The problem is that the production of an oil well collapses over time, but it is unclear which of the many underground branches between more boreholes are (almost) blocked. The idea is to regularly release a set of small measuring systems that have been inserted at the bottom of a borehole. These measuring systems follow the oil stream from the bottom to the surface and take data measurements on the way. The acquired data are read at the surface.
These measuring systems were realised with CMOS chips in plastic balls that can be read externally (see photo) with a ‘fancy’ read-out station. A number of thresholds had to be overcome. For example, there are extreme conditions in a well: the pressure at three kilometres deep in the earth and a temperature of 250 C. Because CMOS chips usually fail at about 180 C, TU Delft performed a study to find root causes and overcome this threshold. They found a way to be able to use CMOS to about 300 C. As a result, it would be possible to produce an ASIC with a microprocessor, non-volatile memory and sensors using a normal CMOS production process.
The prototype system data extraction system (nicknamed “UFO” – Unknown Floating Object) and a number of measuring balls are present in the museum.