It’s not uncommon for an industrial facility to dedicate nearly a third of its energy use to generating compressed air. Unfortunately, not all that is produced is used for processes – some goes to waste. Faulty components can cause leaks through which compressed air escapes, and processes using insufficient pressure can consume more compressed air than they need. But identifying components before they fail, locating leaks early and calculating proper pressure ratios while maintaining cycle time isn’t easy without the right information at the right time.
Yet, many plants don’t currently have a way to access that information at any time, let alone the right one. Operators, technicians or third-party resources may manually collect periodic measurements, but this invites the chance for human error and, if they’re accurate, the resulting spreadsheets or one-off reports are often stale by the time they’re used to make decisions. These facilities may never know the actual condition of their assets, which means leaks can go undiagnosed and air consumption can go unchecked. When maintenance is performed, it may mean fixing equipment when it fails or replacing components on a time rather than health basis, incurring high costs and unplanned downtime.
Luckily, there’s another way. Through the digital transformation of pneumatic systems, facilities can now monitor compressed air consumption in real time and immediately access the valuable data and insights needed to optimize pneumatic processes and advance approaches to maintenance. By using intelligent technologies to make better decisions and take immediate action, facilities can significantly reduce compressed air consumption, enable predictive maintenance and improve sustainability.
Image 1. This dashboard for pneumatics applications from Emerson offers a comprehensive picture of a facility’s pneumatic system performance in one screen, enabling quick, informed decision-making that makes predictive maintenance possible and can optimize energy use.
The Digital Transformation of Pneumatic Systems
The industrial internet of things (IIoT) and industry 4.0 have digitally transformed the way facilities operate, enabling processes that are smarter and more efficient than ever before. But digital transformation is still new to some and may seem abstract or ambiguous. In actuality, it’s quite the opposite.
Digital transformation is a process that a facility system or piece of equipment undergoes that allows end users to see real-time data, make decisions based on it and act based on those informed decisions. Quite simply, digital transformation places the right information in front of the right expert at the right time. It eliminates guessing about process parameters or waiting for equipment to fail. (Image 1)
The digital transformation of compressed air systems can be as basic as adding a smart sensor that measures consumption or as elaborate as connecting an entire line or floor. Both cases open previously inaccessible levels of compressed air data and asset condition, affording operators a clearer understanding of the current, past and possible future state of their pneumatic system. This expertise empowers them to confidently make informed decisions and take quick action.
By using technology to automate and optimize operational processes in this way, facilities put a continuous cycle into motion. This cycle has three stages: See, Decide and Act. In compressed air applications, different smart solutions automate each stage.
See Stage: This stage sets off the cycle, starting at a sensor that creates the appropriate data in a continuous, repeatable and reliable way. In pneumatic systems, this process includes capturing the acceleration and cycles of pneumatic valves and cylinder actuation as well as measuring the volumetric flow rate, pressure, temperature, mass flow rate and flow velocity of compressed air. Such real-time data provides around-the-clock information about the actual health of a facility’s assets and energy consumption and is the foundation for timely, informed decision-making. (Image 2)
Decide Stage: In this stage, the sensor delivers the collected data to a controller or gateway device that continuously aggregates that information in real time and presents trends through an easy-to-interpret visualization tool. At-hand expertise like this empowers operators to make quicker, smarter decisions that drive faster, appropriate actions. (Image 3)
Act Stage: Mobility tools used in this stage send notifications to specific personnel that prescribe clear, necessary actions to take based on the current state of operations. This can include which cylinders are approaching end of life, have an increase in acceleration over time or have already moved past their targeted cycle time. These directives enable personnel to resolve issues before they can slow or shut down operations.
Together, these stages offer valuable analytics; their endless cycle generates a technology loop that enables predictive maintenance while continuously improving expertise and energy efficiency.
Image 2: Emerson’s AVENTICSTM Series AF2 Flow Sensor continuously monitors airflow in pneumatic systems, providing operators with clear, actionable insights regarding flow, pressure and temperature.
Image 3: Emerson’s RXi2-LP Industrial PC runs HMI, historian and analytics applications right at the machine. This powerful IPC enables real-time control of pneumatic systems in a compact size.
Minimizing Unplanned Downtime Through Predictive Maintenance
Maintenance is inherent to all industrial facilities. In pneumatic systems, valves wear out over time, causing leakage that leads to excessive compressed air consumption. Some systems can have many valves, which can make identifying a faulty one challenging. Leak troubleshooting can be time-consuming and, with the ongoing labor shortage and skills gap, maintenance personnel may already be stretched thin. There may not be enough staff to keep up with what must be done, and historical knowledge may not exist. When production must stop for repairs, it can be very expensive. For mid-sized food and beverage facilities, unplanned downtime costs around $30,000 per hour.
It’s in a facility’s best interest to prevent issues before they can arise. That’s where predictive maintenance comes in. Predictive maintenance can significantly decrease operations and maintenance costs and eliminate unplanned downtime.
Now that we know how the See-Decide-Act cycle works, it’s easy to imagine how the digital transformation of a pneumatic system makes predictive maintenance possible. Let’s consider pneumatics maintenance in food and beverage processing where compressed air is heavily used to actuate auxiliary and hygienic valves through discrete pilot valves or valve systems.
Auxiliary and hygienic valves can be used to heat, cool, dose or fill additives and ingredients to sanitary valves that transport consumable goods or beverages. Connected smart sensors, controllers and edge gateways capture a more complete picture of valve health, enabling the system to detect when valves are worn or nearing the end of their service life. If such a valve is detected, the system immediately sends an alert to maintenance personnel, who schedule planned maintenance.
The ability to predict potential problems before they occur helps reduce unplanned downtime while real-time root-cause analysis clearly prescribes the appropriate action to take. Automated troubleshooting and analytics further reduce maintenance time, increase equipment availability, improve productivity and, in the case of leaks, save energy.
Optimizing Energy Use for Greater Sustainability
Today’s smart pneumatic devices provide a more complete picture of pneumatic system performance. This gives facilities a better understanding to effectively control energy use by locating and diagnosing leaks and optimizing compressor system pressure.
Air compressors consume a lot of energy to operate, and that amount is often more than needed for normal operating conditions. It’s estimated that 20 to 30% of a typical facility’s energy consumption goes to producing compressed air. When mid-sized facilities often spend $2.5 million a year on energy, any reductions in compressed air consumption can equal substantial savings. The more a facility can track leaks and balance an operated valve, the greater control it has over its energy use. Optimizing the compressed air a valve consumes while still achieving the required cycle time limits the amount of work the compressor must do and allows it to only consume the energy it truly needs to do it.
By digitally transforming their pneumatic systems to diagnose leaks and calculate proper pressure ratios, facilities can typically see a 10 to 20% reduction in compressed air consumption and energy costs and a 5 to 10% reduction in CO2.
Taking the First – or Next – Step
No matter the size of their operation or how far along on their i4.0 journey they already are, facilities can begin or continue digitally transforming their pneumatic systems. Operations that are ready to take the next step can request a workshop with a comprehensive solutions provider that offers proven expertise, sensors and hardware. In this workshop, the provider works with a facility to pinpoint challenges and prioritize solutions to implement. It’s important to note that no application is the same; digital transformation works best when it’s deployed on a case-by-case basis working closely with a proven provider.
For those just starting their digital transformation journey, the saying is “start small, scale fast.” A low-barrier entry into IIoT is to focus on one key domain or challenge, even one machine, then use lessons learned to scale up. Some providers offer turnkey, vertically integrated solutions that can include everything from components to sensors, controllers to analytics that enable facilities to receive the value of digital transformation at the level that is right for them. For facilities that are farther along, providers can deploy analytics based off their existing sensor and controller infrastructure with edge analytics, too.
Digital transformation doesn’t have to be complex. A pragmatic approach of See-Decide-Act can help facilities kickstart their journey. Through this process, real-time information can be collected and converted into useful analytics and insights that can be used to enable predictive maintenance and optimize energy use.
About the Author
Amit Patel is marketing manager for digital transformation within the Fluid Control & Pneumatics business at Emerson. He focuses on driving the marketing direction and strategic vision for the Industrial Automation segment. Amit earned his Bachelor of Science degree in electrical engineering from the New Jersey Institute of Technology and holds a Six Sigma Black Belt for Process Improvement using statistical methodologies. For more information on Emerson visit https://www.emerson.com/en-us.
All photos courtesy of Emerson.
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