Space-Saving V-Cone® Flow Meter Gives Municipal Water Engineers Lots of Elbow Room
October 3, 2016
Municipal water treatment engineers tasked with measuring liquid flow in close proximity to an elbow will find the self-conditioning V-Cone Flow Meter from McCrometer reduces the straight pipe requirement between the two devices by up to 70-percent versus other meters, resulting in significant real estate and installation labor savings that can actually exceed the cost of the instrument itself.
The space-saving V-Cone operates over a wide flow range of 10:1 with low head loss and supports line sizes from 0.5 to greater than 120 inches. Accuracy is ±0.5%, with a repeatability of ±0.1%. Municipal water engineers can rely on the V-Cone Flow Meter for consistent performance and low cost of ownership because it requires virtually no recalibration or maintenance over an exceptionally long life. The versatile V-Cone is also easy to locate and install, making it ideal for water plant expansions or retrofits as well as new facilities.
The compact V-Cone reduces flow meter straight pipe run requirements by up to 70 percent or more and needs only 0-3 straight pipe diameters upstream and 0-1 downstream to operate effectively. It is especially useful in water well production, crowded pumping stations, filter and pipe galleries and finished water applications.
The V-Cone’s unique no-moving parts design provides built-in flow conditioning, which almost eliminates the upstream/downstream straight pipe runs required by nearly all flow meter technologies. Typical flow meter installations may require 10 to more than 40 straight pipe diameters upstream from the meter and 5 or more straight pipe diameters downstream to eliminate the effects of swirl and other pipeline disturbances caused by elbows, valves and other devices that negatively affect measurement accuracy.
In comparison to traditional instruments such as magnetic and venturi flow meters, the V-Cone’s design is inherently more accurate because the flow conditioning function 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 volumetric fluid flow rate.
