Coriolis flowmeters keep watch on gas network

An Emerson Process Management - Flow Division product story

Edited by the Engineeringtalk editorial team Sep 10, 2002

Micro Motion Coriolis flowmeters have been employed by Transco, the company that manages the UK natural gas transmission system

Micro Motion Coriolis flowmeters have been employed by Transco, the company that manages the UK natural gas transmission system, based on independent high-pressure flow calibration test results from NMI, the Netherlands Metrology Institute.

Micro Motion Coriolis meters have demonstrated reliability and accuracy in gas metering applications on process and storage plants for many years.

This experience encouraged Transco to consider the Micro Motion Coriolis technology for use as a natural gas custody transfer meter.

Recognition of the meter suitability follows a successful series of flow calibration tests on actual high pressure natural gas flows at the NMI test facilities in Holland.

Micro Motion Coriolis meters demonstrated that: "As part of a metering system, the uncertainty of measurement can be demonstrated to meet the requirements of +/-1% volume flow, using Monte Carlo or RMS methods".

Immediate benefits for fiscal or custody transfer metering stations used on industrial or large commercial sites are that the metering skid using a Micro Motion Coriolis meter is much smaller and simpler than the conventional skid design, uses no moving parts, and has no lubrication or filtration requirements.

Installation pipework can be much simpler: there is no need for long straight pipe runs upstream and downstream of the meter.

Using multivariable digital technology the meter provides direct outputs of corrected and uncorrected gas flow rate and totalised flow, as well as gas mass flow rate and totalised mass flow and temperature.

All this is from an installation that is effectively a single unit positioned between two standard flanges: the lack of separately installed pressure and temperature measuring devices makes for simplified electrical and pipeline connections, with attendant increased pipeline integrity.

Micro Motion Coriolis meters have been applied to gas metering on process and storage plants for many years.

Typical Micro Motion Coriolis applications include monitoring natural gas feed-lines, combustion control systems, and refinery fuel gas measurement.

Further applications have shown the meter capable of working very accurately and reliably on propane and butane flows - initially for custody transfer between the refinery and bottling plants for the liquid fuels, and for gas blending control when accurately mixing the fuels.

Recently Micro Motion units have been the most common meter fitted into Compressed Natural Gas (CNG) fuel dispenser systems.

The recent publication of an AGA-11 tech note for Coriolis mass flow technology for natural gas measurement further describes the applicability of Coriolis as the industry choice for high flow-rate gas measurement applications.