Compressed Air

Two ways smart pneumatics maximize energy savings

Flow, pressure and temperature data included

By Dieter Michalkowski and Chris Noble March 15, 2021
Courtesy: Emerson

Whether driven by sustainability goals or environmental standards, manufacturers want to reduce energy consumption and greenhouse gas emissions. Smart pneumatics make compressed air a prime opportunity to save a remarkable amount of energy and reduce overall emissions.

In the past, manufacturers had no clear or simple way to analyze machine air consumption. However, more and more are discovering the energy-saving benefits of smart pneumatics to collect flow, pressure and temperature data and better understand equipment energy consumption.

This digital transformation of machines can be scaled for pneumatic operations of practically any size. Operators capture and process data from pneumatic and other machine elements to unlock actionable, energy-saving insights. Transforming the raw data from a smart pneumatic system into something actionable is the key to lowering energy costs, not to mention reducing downtime, enabling faster cycle times and increasing overall productivity, too.

Wasted energy in pneumatic systems can be staggering. To put a number on it, manufacturing plants typically lose 30% of compressed air just due to leakage alone. Wasted energy leads to machine downtime and, of course, increased energy costs.

Compressed air is used throughout industrial facilities to help operate machinery and processes, so its prevalence makes it pivotal to lower year-over-year energy costs. In fact, improvements in the compressed airflow of a plant’s machinery of even just a few percentage points can mean tens of thousands of dollars saved in energy costs each month, depending on the size and nature of the equipment. That can translate to hundreds of thousands of pounds of carbon dioxide (CO2) emissions saved. By using smart pneumatics like software monitoring and notification solutions to detect leakages, manufacturers can often reduce their compressed air energy spend by 10% to 20% and reduce their CO2 footprint by 10%.

However, for many manufacturers, this transformation remains a goal rather than a reality. While they may acknowledge the benefits, over 70% of manufacturers lack a data analytics plan and a clear blueprint for success. The Industrial Internet of Things (IIoT) and other enabling technologies are considered too complex, costly and time-consuming to implement.

But that doesn’t have to be the case. Manufacturers can invest in plug-and-play smart pneumatic solutions that keep installation time and costs to a minimum. Manufacturers can take the first step toward digital transformation by taking a closer look at how these smart pneumatics save energy in areas where leakages and losses occur.

Plants can improve compressed energy savings through digital transformation in two primary ways.

Detect compressed air leaks

The most obvious way manufacturing plants lose energy in pneumatic systems is through leakage. Leaks cause the average manufacturing plant to lose around 35% of compressed air annually. When pneumatic system components are subject to wear, leakage can occur and grow over time. The larger the leak, the more significant the energy loss. This results in wasted energy, a bigger carbon footprint and higher operating costs. Some operators can lose more than $50,000 per year, per machine!

Figure 1: Users get the real-time data they need to reduce energy consumption by monitoring their machines with a smart pneumatic analyzer. Courtesy: Emerson

Figure 1: Users get the real-time data they need to reduce energy consumption by monitoring their machines with a smart pneumatic analyzer. Courtesy: Emerson

In addition to energy loss, a compressed air leak can cause system pressure in machinery to fluctuate, affecting equipment efficiency and even production. As a result, a machine may have to work harder to compensate. This unnecessary cycling and increased run time can raise energy costs, decrease equipment service life and increase maintenance.

To detect and locate compressed air leaks, companies bring in technicians with ultrasonic equipment to test for them. But leaks can often appear, persist and grow in the time between these periodic, stopgap visits.

Smart pneumatics, on the other hand, continuously monitor airflow. Some sensors can collect and provide real-time insights on flow, while also capturing pressure and temperature data in the feed line, enabling advanced diagnosis of the operating parameters. These solutions can often easily retrofit to existing machines with the use of edge gateways. Around-the-clock software monitoring can detect leaks in near-real time. The software identifies the machine in question and sends notification alerts directly to maintenance staff so they can further investigate.

By detecting leaks in near-real time, smart pneumatics can lower compressed air energy spend by 10-20% and reduce a plant’s CO2 footprint by 10%. Addressing compressed air leaks earlier also reduces both planned (time used to test for air leakages on each machine) and unplanned downtime and improves overall equipment efficiency (OEE).

Optimize consumption

Some manufacturers may not have the full picture when it comes to the relationship between air pressure and airflow. This means they may not actually know the optimal consumption point of compressed air for their manufacturing process. The air pressure in their industrial machines may be higher than it needs to be. When equipment consumes more compressed air than necessary, it consumes more energy, which raises energy costs and CO2 emissions.

Smart sensors plus an edge computing device can collect data about air pressure and airflow. By analyzing the edge analytics of the pneumatic system, plants can get a clearer picture of the relationship between air pressure and flow. By lowering the overall pressure of their pneumatic system, they can reduce the airflow to a certain point while maintaining the same cylinder cycle time.

Finding the optimal ratio between pressure and flow can lead to a 10-20% reduction of compressed air consumption and energy costs, as well as a 10% reduction in CO2 footprint, without affecting production. This allows manufacturers to maintain current cycle times in production, but with lower energy consumption, costs and CO2 emissions.

Figure 2: Smart pneumatics analyzer visualizes and displays live data from flow sensors. Courtesy: Emerson

Figure 2: Smart pneumatics analyzer visualizes and displays live data from flow sensors. Courtesy: Emerson

Real-time data, savings

By using smart pneumatics to detect leaks and monitor air consumption, industrial manufacturers can save a significant amount of energy. Manufacturers can work with their automation partner to start on the area or areas of focus that make the most sense for their situation, budget and goals.

For example, a global producer serving the automotive industry recently took steps in its digital transformation by focusing on energy lost through compressed air leakage and air consumption. The company wanted to reduce energy consumption by using an IIoT-enabled energy management tool on an existing production line. They partnered with Emerson, a leading supplier of automation solutions, to monitor and measure the amount of energy the line used.

Like most brownfield applications, this production line included various legacy equipment that came from different suppliers. A power supply, Ethernet bus coupler, power meter (one per circuit) and IO-Link, which included eight available ports for sensors, made up each meter box. Current transformers were located either inside or outside the meter box, and these modules all had to be installed upright to allow for air circulation. Making this setup even more complex, there were a limited number of Ethernet access points to work with. To expand would require considerable investment.

Figure 3: Air flow sensor measures flow, pressure and temperature and monitors air consumption in pneumatic systems. Courtesy: Emerson

Figure 3: Air flow sensor measures flow, pressure and temperature and monitors air consumption in pneumatic systems. Courtesy: Emerson

To meet the needs of this complex setup, Emerson recommended its AVENTICS Series AF2 Sensor, an easy-to-use airflow sensor that measures flow, pressure and temperature and monitors air consumption in pneumatic systems.

The AF2 is ideal for a collection of legacy machines like this for a couple of reasons. First, the compact sensor is easy to assemble and can be installed on existing machines and pneumatic systems. Second, the AF2 has IO-Link and Ethernet communication options. The sensor is easy to integrate into air preparation units and gives manufacturers the option to operate as a stand-alone version. With a colored, rotatable LED display that provides clear feedback, the AF2 sends notification alerts to users when it detects a leak so they can take action. This simple IIoT-enabled device allowed the company to invest in energy savings while keeping installation time and costs to a minimum.

After choosing a sensor, Emerson helped the company monitor and measure the amount of energy the line used by temporarily connecting the AVENTICS Smart Pneumatic Analyzer (SPA) to one machine. The SPA, which provides pneumatic system analysis at a glance, recorded, analyzed and visualized the line’s air consumption during the production process. The team was able to read the real-time air consumption, which the SPA displays in norm liters per minute (Nl/min), alongside average and maximum values to quickly identify trends and anomalies.

The data collected from the SPA helped the company decide whether Emerson’s PACSystems RXi2-BP Edge Computing Device was worth investing in. In simple terms, the PACSystems RXi2-BP Edge Computing Device interprets and displays all incoming AF2 sensor data. Using mathematical algorithms, it digitizes then translates the data into straightforward, user-friendly information. This information is recorded and displayed on a live, web-based dashboard and gives users even more energy insights without additional software. The SPA data revealed that the PACSystems RXi2-BP Edge Computing Device would indeed help the company save energy and its associated costs, so the company decided to make the investment.

In total, Emerson supplied approximately 180 AF2 flow sensors to meet the production line’s needs, along with the PACSystems RXi2-BP Edge Computing Device. This all-in-one energy-saving sensing and edge computing solution monitors pneumatic air consumption and generates and interprets machine data, giving the automotive producer actionable insights and a more complete picture of what’s happening in its plant. As a result, the company has successfully found areas for improvement, including reducing peak power consumption, optimizing maintenance costs and avoiding downtime, and plans to continue optimizing its machines to use less energy.

Figure 4: Edge computing device interprets incoming sensor data into easy-to-understand, actionable information. Courtesy: Emerson

Figure 4: Edge computing device interprets incoming sensor data into easy-to-understand, actionable information. Courtesy: Emerson

Toward a transformation

Across all industries, energy management continues to be a top priority for industrial facilities. As concerns about energy consumption and carbon emissions grow, monitoring compressed air in pneumatic systems is a critical opportunity for reducing emissions and lowering energy costs. When machines aren’t monitored, neither is their energy consumption. Leaks and losses are free to grow, problems that could be solved early deteriorate into late-stage quality issues and significant amounts of energy are wasted.

Yet the road to digital transformation that unlocks compressed air energy savings looks different for everyone. Like any transformation, digital transformation is a process that unfolds at its own pace, depending on a plant’s unique circumstances. To successfully start saving energy through digital transformation, it’s important to work with an automation expert who knows smart pneumatics and the unique characteristics of fluid power applications. When you have access to the right expert, knowledge and tools, you can realize your compressed air energy saving — and digital transformation — goals.

Dieter Michalkowski and Chris Noble
Author Bio: Dieter Michalkowski is global account manager, fluid control & pneumatics at Emerson. Chris Noble is business development, food & Beverage, packaging and IIoT consultant at Emerson.