Flow meters are devices that are primarily used to measure and monitor the flow of gases and fluids through an industrial application. Flow meters also measure other parameters of the liquids and gases. There are various types of flow meters such as electronic, ultrasound and magnetic. Some typical examples of industries where flow meters are commonly used are the chemical industry, the energy sector, and the food and beverage industry, etc. Flow meters are also used to regulate and control the flow of various liquids.
These meters are available in a variety of forms such as: multi-jet flow meters, volumetric flow meters, open channel flow meters, ultrasonic flow meters, etc. Based upon the nature and the viscosity of the fluid, an appropriate flow meter can be chosen. Some common considerations while choosing a flow meter are that the calibrations must be adjusted to: the viscosity of the liquid, operating pressure, temperatures and flow rate; all of which must be measured in advance.
Some of the most common types of flow meters include coriolis, magnetic, ultrasonic, vortex, turbine and multiphase.
- Coriolis meters are twisting meters that are used to measure the mass flow as opposed to the volumetric flow. These meters are known for their accurate readings however their size is limiting. Coriolis flow meters can cost quite a bit, but they usually carry a low maintenance cost. This style of meter is used for clean liquids and gases which flow at medium to high velocity, in pipes six inches and under.
- Magnetic flow meters are also high costing meters that are generally used for water applications. They are limited to conductive fluids and they operate on a voltage generator.
- Ultrasonic flow meters are becoming more popular in the industrial world as they are quite effective for measuring natural gasses. These meters are non-intrusive and they have no pressure drop. It is important that ultrasonic flow meters work on clean fluids.
- Vortex meters are mainly used as an alternative to differential pressure flow meters. These meters work best with clean, low-viscosity, medium to high speed fluids.
- Turbine meters are mainly used for both liquids and gas. They operate best for applications that have steady, high-speed flows.
- Multiphase meters are advanced types of flow meters which accurately measure the flow rates of oil, gas, and water. These flow meters don’t have any moving parts and cause no separation or mixing.
With the advent of technology, flow meters use a variety of principles to measure the flow of liquids such as the Doppler Effect, thermal flow, etc.