Aquametro Oil & Marine Viscomaster, Installation And Operation Manual

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8 VCS - Viscomaster™
3.1.4.1 Boundary effect
Boundary effect refers to the distortion in the wave forms in the process fluid that are caused by reflections from
the pipe wall. If the pipe wall is within the meter's effective measurement region, the boundary effect produces
measurement inaccuracy.
The factory calibration compensates for the boundary effect. The meter can be calibrated for 2-inch, 2.5-inch, or
3-inch pipe. If the meter is installed in a pipe, that does not match the calibration size, the compensation will be
inaccurate, and process measurement will be inaccurate.
Verify that the meter was calibrated for the pipe size you plan to use.
3.1.4.2 Flow rates
Maintain constant flow rates and velocities that are within the limits specified for the meter. The fluid flow
provides a steady heat flow into the meter installation, and the flow rate influences the self-cleaning of the
meter tines, the dissipation of bubbles, and the solid contaminants around the meter.
If you install the meter in a bypass configuration (such as in a flow-through chamber), use a pressure drop, pitot
scoop, or a sample pump to maintain flow. When using a sample pump, place the pump upstream from the
meter.
3.1.4.3 Entrained gas
Entrained gas, or gas pockets, can disrupt the measurement of a fluid. A brief disruption in the signal caused by
transient gas pockets can be corrected in the meter configuration, but you must avoid more frequent
disruptions or serious gas entrainment to ensure accurate and reliable fluid measurement.