When the village of Windsor, N.Y., replaced a mechanical flowmeter with an electromagnetic flowmeter way back in 2003, it was with high hopes that newer technology was less prone to failure and needed less maintenance. Those high hopes were fully realized, as the meter was put to the test after being fully submerged in two damaging flood events.
KROHNE’s AQUAFLUX electromagnetic flowmeter performed flawlessly while under the noxious floodwaters, even though submersible capabilities weren’t intended as qualities of the original design.
The village, which lies along the Susquehanna River, had replaced an older mechanical flowmeter that continually failed and needed constant maintenance. The flowmeter, installed in the village’s water pump-house, is used at the aquifer source for potable water distribution. It measures the volumetric flow rate of all the water extracted from the wells and pumped into the village distribution system and storage tank. The village pumps from two 30-hp submersible wells.
The flowmeter monitors and tracks usage, metering what is dispensed to people’s homes.
"The flowmeter is a very valuable device that enables us to know how much water we pump, conduct daily tracking, and alert us to when things are drifting," says Ron Harting, Windsor deputy mayor and technical director, O’Brien & Gere. For example, if usage increases inexplicably, managers look for a leak somewhere in the system. At the end of the year, information collected from the meter is used for required reporting to the state and the Susquehanna River Basin Authority. O’Brien & Gere is a Syracuse, N.Y.-based engineering and construction company.
Changing technologies
The village changed technologies in the hopes that an electromagnetic flowmeter would be more reliable than the previous meter, a paddle wheel sensor with a small propeller. "Obviously moving parts tend to wear out, and that meter was very expensive to repair each time," explains Harting.
KROHNE’s AQUAFLUX electromagnetic flowmeter is made with a fully welded housing and is extremely tight and resistant to corrosion. It is lined with durable polypropylene or KTW-approved hard rubber. It comes standard with a IP 67 enclosure (equivalent to NEMA 6), and is suitable for ground burial.
According to Harting, many municipalities may hesitate to use new "magmeter" technology, feeling most comfortable with older mechanical flowmeters that may go back to the 1960s. Some are concerned that electronic devices can be reset, whereas an old mechanical meter may be more exempt from interference. In Harting’s view this concern is not justified and the electromagnetic flowmeter is a quantum leap in technology that is well worth the investment.
"The cost of each mechanical meter repair was about as much as the total cost of the KROHNE magmeter," says Harting. "With no moving parts and the rugged design, I’m guessing the life expectancy of the AQUAFLUX magmeter will be close to 20 years."
Changing environments
In June 2006, the village, and its chosen flowmeter technology, faced an important test, as Windsor was hit by a major flood. The magmeter was totally submerged in floodwaters for three days. The total water depth was about four feet, with the magmeter residing about two feet below the water surface.
Once the waters finally receded, Harting inspected the pump house and found that, after merely wiping off the mud, silt and debris from the AQUAFLUX meter transmitter’s face, the display was fully functioning.
Harting says for most systems submergence typically equates to equipment failure. "I have witnessed countless magmeters and similar instruments when subjected to submergence. Although the flow tube and transmitter were purchased as NEMA 4X, the inherent IP 67 rating was a feature and benefit we gained without additional cost or effort."
In 2011, the floods returned and the magmeter was again fully submerged for about two days, with the same results. The facility is about 150 yards from the river proper and the flooding was due to heavy rain. Harting believes this type of storm is happening more frequently and flooding issues will persist.
During the two storms, the village kept pumping until it believed the chlorination system stopped working. At that point it shut down the wells, stopping the flow through the magmeter, but never shutting power off to it.
All in all, the village is extremely satisfied with the magmeter. Harting expects this will continue as long as there is no material coating or erosion of the inside lining. He is even more pleased that the magmeter performed well in an environment it was not designed for and exceeded NEMA ratings.
KROHNE is a world-leading manufacturer and supplier of solutions in industrial process instrumentation. KROHNE offers supporting products and services for one-stop-shopping and in industries as widespread as oil & gas, water & wastewater, chemical & petrochemical, food & beverage, power, minerals & mining and marine.
