McCrometer introduces V-cone flow meter

Jan. 2, 2008
McCrometer has unveiled the V-Cone FPSO flow meter.

Offshore staff

HEMET, California -- McCrometer has unveiled the V-Cone FPSO flow meter.

The new V-Cone design has no moving parts and provides built-in flow conditioning, which nearly eliminates the upstream/downstream straight pipe runs required by most flow meter technologies.

The flow meter only needs 0 to 3 straight pipe diameters upstream and 0 to 1 downstream to operate effectively. It fits in tight installations aboard FSPO vessels and in subsea applications. Accuracy is +0.5%, with a repeatability of +0.1%.

It operates over a wide flow range of 10:1 and supports line sizes from 0.5 to 120 in. (1.2 to 305 cm). It requires virtually no recalibration or maintenance and conforms to the American Petroleum Institute's API 22.2 testing protocol for differential pressure flow measurement devices.

Unlike traditional DP instruments such as orifice plates and venturi tubes, the flow conditioning function of the V-Cone flow meter is built-into the basic instrument. The V-Cone conditions fluid flow to provide a stable flow profile that increases accuracy. It features a centrally-located cone inside a tube. The cone interacts with the fluid flow and reshapes the velocity profile to create a lower pressure region immediately downstream.

The pressure difference, which is exhibited between the static line pressure and the low pressure created downstream of the cone, can be measured via two pressure sensing taps. One tap is placed slightly upstream of the cone and the other is located in the downstream face of the cone itself. The pressure difference can then be incorporated into a derivation of the Bernoulli equation to determine the fluid flow rate.

The cone's central position in the line optimizes the velocity of the liquid flow at the point of measurement. It forms very short vortices as the flow passes the cone. These short vortices create a low-amplitude, high-frequency signal for excellent signal stability. The result is a highly stable flow profile that is repeatable for continuously accurate flow measurement.

02/01/2008