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 ondifferential pressure, vortex or turbine principles. They all have in common, that plant operationsneed to be shut down for installation and maintenance. The first two are limited in their flowranges, but whilst turbines cover a wider flow range they utilize moving parts - and hence havewear-and-tear issues.The ideal way to measure any fluid flow inside a pipe would obviously be done from the outsideof the pipe, if the flow measurement principle would cover a wide flow range with good accuracyand be virtually maintenance free.Clamp-on Ultrasonic Flow Measurement (USFM) technology has been commercially availablefor over two decades. It always met the desire to measure flow non-intrusively, albeit often notvery accurately and restricted to only liquids. Micro-processor technology and focused researchhas in recent years widened the application envelope, while at the same time making clamp-ontechnology accurate and cost competitive.This paper outlines recent technical developments which enable USFM technology to measureliquids as well as gases. Performance and costs of USFM technology will be compared with thetraditional flow metering methods still in use today. Some specific application examples will beidentified where USFM adds value to gas processing operations.