Industrial flow meters are the most popular devices used by professionals in various industries. Water flow devices measure the liquid flow in pipes and come in different types. Before a user settles for an appropriate flow meter technology, there are things you have to consider:
- Water measurement applications
- Desired range
- Budgetary terms
- Process conditions
- Accuracy
- Maintenance
Flow measurement is the quantity of fluid movement, which gets measured in various ways. One of them is through the Positive-displacement flow meters, which accumulate a fixed fluid volume and calculate the number of times it gets filled to measure flow. Other methods depend on forces generated by the flowing stream overcoming a known constriction. Then you get the flow measurement by calculating the velocity of liquid over a known area.
Four Significant Water Flow Meters
professionals can choose from these four water flow meters depending on their water flow measurement application. These include:
- mechanical water flow meters
- ultrasonic flowmeters
- vortex volumetric flowmeters
- magnetic flow meters.
Mechanical Water Flow Meters
these mechanical meters can be pretty economical, so they’re the most common devices. They use a shunt or a propeller to perform flow measurements and find the speed of the water flowing through the pipe. They have high accuracy for measurements, and pressure, viscosity, or temperature are not affected.
However, these meters can only work best with clean water as slurry or dirty water may clog the pipe leading to high maintenance costs. Also, they will not do well if the water flow turns low.
Ultrasonic Water Flow Meters
Ultrasonic uses ultrasound to calculate the speed of fluid passing through the pipe and measure the volumetric flow. So, the ultrasonic signal in a transit-time ultrasonic liquid flow meter gets transmitted downstream, towards the direction of the flowing fluid. And another transmission goes against the flowing fluid upstream.
To find the velocity of the flowing liquid, first, you have to find the difference between the time for the sonic pulse traveling downstream and the time-traveling upstream. The meter uses this fluid velocity to calculate the volumetric flow rate in the pipe.
They measure the flowing fluid by clamping transducers on a pipe, and you can place these on the outside. These don’t come close to the liquid, and they provide non-invasive flow measurement.
Magnetic Flow Meter
As per Faraday’s Law of Electromagnetic Induction, liquid produces a voltage when it streams through a magnetic field. And this calculates the speed of the fluid in a pipe and measures the volumetric flow. The faster the fluid flow, the higher the voltage produced. It’s directly proportional to the water movement. And by using electronics, the voltage signal gets refined into the volumetric flow rate.
Though the mag meters can measure the reverse flow, they can only show an intermediate accuracy. That makes them inappropriate for custody transfer applications and is not the best for flow measurement of pure water.
Vortex Flowmeter
Many industries use vortex flowmeters to measure fluids, liquids, steam, and gas volume flow. They use a sensor tab that flexes from side to side as each vortex flows along, creating a frequency output proportional to the volumetric flow rate. And this is popular equipment because it’s easy to install, has less potential for leaking, offers low power consumption, and requires minimal maintenance as they have no moving parts.
In Conclusion
Some flow meters will work better in specific applications than others. So, professionals need to find the best type of water flow meter depending on the particular application. Other things worth considering include process condition, accuracy, budgetary, and maintenance. They can always check with the manual instructions or ask the seller for clarification about the appropriate device if unsure before buying the equipment.
