Dynamic factory testing is an important step in the manufacturing of ultrasonic meters for custody transfer and other high accuracy petroleum applications. By utilizing a multiple product, high accuracy test system and a proper test program, a meter’s performance can be simulated over a wide flow and viscosity operating range. The test results give the user a detailed graph of the meter’s performance over the actual site operating parameters. The test verifies the meter’s performance prior to shipment but more importantly provides k-factor sensitivity to optimize measurement accuracy throughout the operating range. This paper outlines the theoretical basis and fundamentals of dynamic testing. It illustrates the process with data from an ultrasonic meter factory test recently conducted for a North Sea operating company. The meter was a 12 inch multi-path ultrasonic meter operating over a flow range of 636 to 1,113 m3/h (4,000 to 7,000 BPH) and a viscosity range of 5 to 350 cSt.
The details of dynamic testing and the relationship between the measurement accuracy of a meter and dynamic testing will be the focus of this paper. It will include:
• The fundamental operating principle of ultrasonic
• Fluid dynamic properties such as boundary layer and flow profiles
• The characteristics of the flow profiles in the different flow regimes that affect crude oil measurement
• The dynamic operating range of crude oil meters
• How dynamic testing is used in factory testing to verify the performance of a meter
• Results of the 12 inch multi-path ultrasonic meter factory testing
This paper will provide the necessary information to fully understand the basis and proper methods for dynamic testing to determine the operating performance of an ultrasonic meter.
