Steam flow meters are essential for a plant´s efficient operation and safety. There are multiple steam flow meter types and they all have their advantages and disadvantages for different applications. This article will help you find a suitable steam flow meter depending on the process required.
Steam flow meter types
The most common types of steam measurement are multivariable transmitters, with vortex technology or a DP Flow transmitter and portable ultrasonic flow meters. Both have their upsides but it is preferable to use vortex steam flow meters in most cases.
Multivariable transmitter for steam measurement
Differential Pressure flow meters
The multivariable transmitter based on DP Flow measures differential pressure, static pressure, and temperature. Then it calculates flow rate, measuring with a basic element like an orifice plate.
Here, the benefit of the multivariable is its popularity; we’re using industry-standard tech with a familiar process. However, these devices need primary elements, which often bring a host of problems. For example, if we choose an orifice plate, then we’ll find a rather user-unfriendly installation. Also, primary elements usually come with tedious and complex calibration and verification.
To know more about gas flow meter, you can read our article on choosing the right natural gas flow meter
Setting up a multivariable transmitter for steam flow measurement
Despite its popularity, multivariable transmitter steam measurement has its limitations. Setup can become very complicated: most of the time we need specific software that guides you through it. Moreover, you’ll need a license for access and the interface for most of the software and it needs to be set up in a field transmitter.
The high temperature can also become a problem. Because of it, we are mostly limited to mechanical parts during setup and the device should be placed far away from the sensor.
Lastly, the mechanical parts can make measurements less accurate. That means regular checks on everything to make sure it all works the way it should.
Vortex steam flow meter
The second option for steam flow measurement with a multivariable transmitter is vortex flow meter. Because the vortex measures the mass flow, via pressure and temperature compensation and it has a simple setup. It does need a minimum velocity to measure accurately. But in the end, the installation will be easier and cheaper than if we choose a multivariable transmitter with an orifice plate.
The vortex’s low profile means it won’t capture the full flow range. Fortunately, it’s not a big issue for steam, so you don’t have to worry about that. Also, you can find vortex meters with high-level steam diagnostics for better plant efficiency.
Vortex steam flow meters are the best solutions for steam measurement available today. Their main advantage is that they offer faster diagnostics and most of the devices today even have self-diagnostic functions. Furthermore, vendors guarantee accuracy and stability, which means that we won’t need to calibrate the device every year.
Last but not least, a broad range of vortex steam flow meters come with steam quality measurement features, which can be used to improve steam production.
Ultrasonic steam flow meter
As far as ultrasonic steam flow meters go, we’ll find just a few. But we can get an ultrasonic flow meter with the steam measurement function, for superheated steam and saturated steam. The accuracy will not be as good as the vortex or the DP Flow, but the long term stability, because of no maintenance or recalibration, is an advantage that can make increase the interest for these flowmeters.
Other type of flow meters
We must know that there are other technologies to measure steam, like Coriolis flow meters, but usually, the price vs the advantages against vortex or DP flowmeters are not justifying the price of a Coriolis flow meter. This is the reason behind is not used in most cases.
If we want quick configuration and installation, we can go with a vortex steam flow meter. On the other hand, if we prefer a more traditional solution, we can use a multivariable transmitter with an orifice plate.
To know more about steam flow meters, you can get in touch with our engineers and we will be happy to help.