We hear about so many “smart” things in the plant that it might be easy to discount this descriptor. But every smart device on a local level can help to create your broader Industrial Internet of Things (IIoT) architecture, providing deeper insights to improve operations.
There’s no question that flowmeters are already important in process automation as instruments measuring flow or density, for example. A smart meter can not only do that more effectively, it can also give critical insight into bigger issues across the plant.
“Modern flowmeters have the ability to improve performance across the plant and deliver vital information on areas outside their traditional remit areas, such as improper installations, multiphase flow detection, changing flow characteristics and aeration,” notes Tom O’Banion, director of global chemical application innovation for Emerson Micro Motion.
Self-serving instruments
Intelligence at the local level can include in situ calibration verification, meter sizing and coating detection—all important for keeping the flowmeters operating with minimal intervention.
Costly and time-consuming calibrations can lead to production interruptions, shutdowns and safety concerns. Emerson’s Smart Meter Verification software for Coriolis and magnetic flowmeters enables on-demand calibration verification, done in situ without impacting the process or meter outputs. Algorithms can detect coating, corrosion and erosion in the meter, and the software provides tube coating diagnostics and transparent audit trails.
“In this way, smart meter verification builds intelligence into the flowmeters at the local level so that immediate actions can be taken when process upsets or other challenges occur that have the potential to impact meter performance,” O’Banion says.
Fluctuating process conditions can have considerable impact on meter sizing, requiring flow, instrument and process engineers to continually monitor and react to changing conditions. To determine meter sizing, they must consider the trade-offs between measurement error at minimum flow rates and pressure loss and/or gas velocity at maximum flow rates, O’Banion explains.
The flow range diagnostics within the Smart Meter Verification system can make the necessary decisions immediately. “The diagnostics can verify if the process flow rate is within the operating range of the flowmeter and if the rate is below that used for sizing,” O’Banion says. “In this way, flowmeters and their diagnostics can act more intuitively as part of a broader information infrastructure and in reaction to process upsets.”
The ability to detect when the meter is coated by something unexpected from the process line also provides crucial information not only on the meter’s health but the wider plant process as well.
With the detection of coating, which can affect density measurements, the Smart Meter Verification diagnostics can provide details about when the buildup occurred and can also automatically trigger cleaning cycles without having to go through a distributed control system (DCS). It can then alert the engineer when the clean-in-place (CIP) cycle is complete.
Broader process issues
Smart Meter Verification also provides operators with information on other flow issues across the plant, leading to improved knowledge, operational certainty and productivity, and the acceleration of IIoT strategies.
O’Banion gives an example of how aeration can lead to unreliable flow data. “Aeration can result in gas voids, line blockages and flow tube damping—all of which can have a significant impact on Coriolis meters and their measurement capabilities by reducing tube oscillation,” he says. “Transmitters also often struggle to react to the sensor signal changes that originate due to aeration.”
When a batch of fuel becomes aerated during marine bunkering due to valves not being closed, pumps not being properly started or excessive tank stripping, there can be a significant effect on meter accuracy in addition to poor batches and potential lost revenues, O’Banion adds. “In such cases, instead of waiting for other equipment to detect aeration, Smart Meter Verification can immediately address the problem through a multiphase diagnostic that calculates aeration and its severity, decides whether remedial action is required, and ensures the meters’ continued accuracy.”
The multiphase diagnostic is also widely applicable to other batching applications, such as when aeration impacts the custody transfer process as can sometimes be the case.
Other software from Emerson, Micro Motion Advanced Phase Measurement software, can help operators experiencing frequent and intermittent periods of severe air entrainment. Using an algorithm to determine when there is entrained gas in the process, the software automatically corrects mass and volume flow measurements based on previously measured gas-free values.
