TECHNOLOGICAL DEVELOPMENTS IN CLAMP-ON ULTRASONIC FLOW MEASUREMENT METHODS AS THEY APPLY TO OIL GAS MIDSTREAM OPERATIONS

摘要

Traditional methods in midstream oil and gas flow measurement applications are based on differential pressure, vortex or turbine principles. They all have in common, that plant operations need to be shut down for installation and maintenance. The first two are limited in their flow ranges, but whilst turbines cover a wider flow range they utilize moving parts – and hence have wear-and-tear issues. The ideal way to measure any fluid flow inside a pipe would obviously be done from the outside of the pipe, if the flow measurement principle would cover a wide flow range with good accuracy and be virtually maintenance free. Clamp-on Ultrasonic Flow Measurement (USFM) technology has been commercially available for over two decades. It always met the desire to measure flow non-intrusively, albeit often not very accurately and restricted to only liquids. Micro-processor technology and focused research has in recent years widened the application envelope, while at the same time making clamp-on technology accurate and cost competitive. This paper outlines recent technical developments which enable USFM technology to measure liquids as well as gases. Performance and costs of USFM technology will be compared with the traditional flow metering methods still in use today. Some specific application examples will be identified where USFM adds value to gas processing operations.