An ultrasonic flow meter, which promises highly accurate flow measurement in natural gas custody transfer applications with reduced upstream piping requirements and without flow conditioning, has been introduced.

The flow meter compensates for flow distortions owing to pipe bends, shorter straight runs or smaller design footprints and is said to be able to operate in more design configurations without sacrificing accuracy and long-term performance.

The unit aims to reduce installation costs by accommodating compact piping designs while providing measurement accuracy in custody transfer applications.

The Daniel 3418 eight-path gas ultrasonic flow meter from Emerson has passed all perturbation tests for OIML R-137 accuracy class 0.5 with only five pipe diameters in front of the meter and without a flow conditioner. 

It features eight interlocked direct chordal paths, positioned as two British Gas path layouts where the second is the mirror image of the first, allowing the meter to cancel out asymmetrical velocity effects. This design enables the meter to measure flow with greater resolution and accurately calculate swirl, reducing the need for flow conditioning and long upstream piping configurations.

In addition, it has the ability to calculate standard flow and directly integrate with temperature and pressure transmitters, gas chromatographs and flow computers while providing real-time meter and process diagnostics.

The flow meter uses the proprietary MeterLink diagnostic software with specific enhancements designed to mimic the look and feel of the original four-path gas ultrasonic meter interface.

Available in sizes DN250 to DN1050 (10 inch to 42 inch), the meter offers bidirectional flow capabilities, increased flow capacity and no incremental pressure drop, with the aim of reducing measurement risk and minimising operating costs.