API TR 2571

Description

Provides a performance-based methodology for the measurement and reporting of fuel gas consumption. The document provides guidance in the following areas to allow the user to achieve a targeted uncertainty of measurement: — selection of flow meter type; differential pressure (DP), displacement, ultrasonic, Coriolis, vortex, turbine, thermal, and others; — associated instrumentation for measuring fluid properties and flowing conditions, such as pressure and temperature transmitters, densitometers, gas chromatographs; — obtaining and use of gas composition or other analytical data; — design and installation requirements of the measurement system; — inspection, verification and calibration practices of flow meters and their associated accessory instrumentation; and — simplified uncertainty calculations with examples to illustrate the methodology. Techniques are described to assess the uncertainty contribution of individual components of fuel gas measurement systems and overall facility