Design, fabrication and characterization of SAW pressure sensors for offshore oil and gas exploration

This work shows the design, development and measurements of an innovative pressure sensor for high pressure and high temperature environments for offshore oil and gas exploration. The proposed sensor is produced with a simple microfabrication process, which enables large-scale manufacturing, reducing production costs. The advantage of low cost production using these sensors is the ability to design distributed pressure sensors systems at affordable prices to monitor smart wells in oil and gas production. The proposed sensor consists of a two-port SAW device in contrast to the common BAW pressure sensors typically used in the oil and gas industry. A test capsule was designed to measure the device under pressure and the sensitivity obtained by the measurements was found to be 14.8 Hz/psi. The operation range was 0-15,000 psi and the device must operate on temperatures up to 150 °C. Resolution was determined to be 1% of full scale. A capsule to package the sensor and circuits was designed and manufactured in 316L Stainless Steel. Results are very promising and expand the application of different kinds of sensors in the oil and gas industry.