Flow Measurement

The SwRI Metering Research Facility (MRF) is a high-accuracy natural gas flow laboratory used for meter research, calibration, and testing. The MRF provides assistance with flow meter design, development, and calibration; meter station layout and optimization; field meter diagnostics and trouble-shooting; gas sampling methods; and personnel training.

Using a test medium of either natural gas or nitrogen, the MRF provides a broad range of test conditions similar to those experienced in the field. Gravimetric flow calibration standards at the MRF provide NIST-traceable mass flow rate measurement accuracies on the order of ±0.1 to ±0.25 percent, depending on the specific test conditions. Test gas flow rates up to approximately 7,000,000 standard cubic feet per hour can be provided at pressures ranging from near atmospheric to 1,215 psig. Pipe and flow meter diameters from 0.25" to 20" can be accommodated.

To cover the necessary range of test flow conditions, the MRF includes three primary flow systems: a High Pressure Loop (HPL), Low Pressure Loop (LPL), and Distribution Test Stand (DTS). See the operational ranges for all three systems. The HPL and LPL are re-circulating flow loops, while the DTS is a "blow-down" type system. Located at a single site, all three systems are operated from a single control center. While individual gravimetric calibration systems are used as primary flow standards at the MRF, slightly less accurate sonic nozzles, gas turbine meters, and laminar flow elements are also available as cost-effective alternatives. An on-line, laboratory-grade gas chromatograph (capable of resolving hydrocarbon constituents up to C₁₀₊) is used for detailed analysis of the test gas composition.

The Metering Research Facility was constructed by GTI in the late 1980s in direct response to a growing need within the natural gas industry in the United States for improving the state-of-the-art of gas flow measurement. The concept of a natural gas industry metering research and calibration facility was first proposed during the 1980s in the Gas Industry Measurement Plan prepared by the Operating Section of the American Gas Association. The plan recommended the development of an independent, qualified flow test facility that would be operated under the sponsorship of the U.S. natural gas industry. This facility had to be capable of providing performance data on a broad spectrum of meter types and sizes over a wide range of flow conditions. In response, GTI initiated the development of the MRF at SwRI in San Antonio, Texas, in 1987. The initial stage of MRF construction was completed in 1991. Operational enhancements to the facility continued through 1994.

The MRF currently supports a variety of GTI-funded research as well as commercial test and calibration work. The GTI-funded research addresses the priority measurement needs of the natural gas industry of the United States by providing a comprehensive flow measurement research, development, and commercialization program aimed at improving meter performance in the field. Current GTI research includes turbine flow meters, ultrasonic flow meter, Coriolis flow meters, direct energy flow rate meters, and pipeline gas sampling methods. Past GTI research included orifice meters, positive-displacement flow meters, and compact flow meters for residential and small commercial applications.

Flow meter manufacturers and operators also use the MRF for research and development and routine meter calibrations. In cooperation with the Southern Gas Association, the MRF staff also conduct personnel training short courses on natural gas measurement.

To learn more about metering research facility at SwRI, visit www.mrf.swri.org.

Inquiries concerning use of the MRF should be made to:

Edgar (Ed) B. Bowles Jr.
Southwest Research Institute
6220 Culebra Road
P.O. Drawer 28510
San Antonio, Texas 78228-0510
Phone (210) 522-2086
Fax (210) 522-2369

Terry Grimley
Southwest Research Institute
6220 Culebra Road
P.O. Drawer 28510
San Antonio, Texas 78228-0510
Phone (210) 522-2353
Fax (210) 681-9661

Upcoming Workshops/Short Courses:

• Factors in Gas Meter Station Design and Operations Short Course in San Antonio

November 18, 2009