The Vortab Elbow Flow Conditioner from the Vortab Company aims to eliminate the problem of finding room for the recommended straight pipe run needed by electromagnetic flow meters in sewage lift stations, by removing swirl and asymmetric velocity profiles caused by pumps placed too close to the meter.
To provide accurate and repeatable flow measurement, electromagnetic and other types of flow metering technologies require a specific amount of straight pipe run upstream and downstream from the installed location of the meter. The straight pipe runs create a swirl-free and symmetric velocity profile in the pipe that can be measured accurately over and over again.
Measurement problems
When electromagnetic flow meters are placed too close to pumps in sewage lift stations, there can be measurement problems. Sewage lift stations are required to pump wastewater from one elevation to a higher level when gravity flow isn’t feasible for any number of reasons. Often there isn’t enough available plant real estate to support the straight pipe run required by electromagnetic and other flow metering technologies.
The Vortab Company’s elbow flow conditioner eliminates the flow meter upstream piping requirements by conditioning the flow stream into a flow regime, mimicking adequate straight run. In addition to conditioning the flow stream, the 90-degree angle tab-type Vortab Elbow Flow Conditioner eliminates the pipe cost and technician labor for the 5 to 10 upstream and 3 to 5 downstream pipe diameters required by mag meters.
The conditioner was developed using the same tab-type flow conditioning technology as the straight run Vortab Flow Conditioners, which have been laboratory proven and successfully installed in hundreds of plants worldwide. To validate the Vortab Elbow’s design, ball valves, gate valves, out-of-plane and in-plane elbows and swirl generators were installed at the immediate inlet of the Vortab elbow and tested in state-of-the-art gas and liquid calibration facilities.
Irregularities
The conditioner isolates the flow irregularities and conditions the flow stream into a swirl-free and symmetrical velocity profile. Swirl reduction and velocity profile correction occur naturally in long lengths of straight pipe due to diffusion and turbulent mixing. Vortab’s anti-swirl and inclined vortex generating profile correction tabs, projecting from the inside pipe surface, generate vortices that accelerate these natural pipe effects to create a uniform, non swirling, symmetrical flow profile in a much shorter section of pipe.
