Compressed air is a vital component of many industrial processing operations. When compressed air leaks occur in these systems, the results can have a major impact on productivity, safety and costs throughout the facility. These leaks often go undetected, but new tools and methods are making it easier for facilities to detect and correct costly air leaks.
The U.S. Department of Energy estimates that the average facility loses between 20% to 30% of its compressed air capacity because of leaks1. This means compressors are working harder than they should to replace escaping air. Pneumatic tools work less effectively without proper air pressure, so facilities relying on these assets may see reduced uptime as a result.
In facilities that use gases such as oxygen or carbon dioxide, leaks can be costly and dangerous for employees and the environment. For products that require gases to be injected, it can be difficult to regulate the amount of gas traveling through lines when they are leaking, directly impacting product quality.
This article explores how leak detection technology has changed over time, and how new tools are helping companies detect leaks faster and tap into Industry 4.0 networks that streamline maintenance, boost uptime and lower costs.
Technology is changing leak detection methods
The high-pitched hissing sound of air leaks can be hard to detect on a busy manufacturing plant floor. Historically, this challenge led to manual detection methods, where a technician would apply soapy water to pressurized lines to look for bubbles.
Then, ultrasonic sensors became a more popular (and less messy) method for leak detection. This approach requires an experienced technician to carefully listen in via a headset to the high-pitched sounds of air leaks picked up by an ultrasonic sensor. However, the technician would need to be highly educated and have the skill to manage the ultrasonic sensor correctly.
In more recent times, acoustic imagers have completely changed the landscape of air leak detection. They have removed the need for the time-consuming soapy water method and reduced the necessity of having a skilled employee on staff who can operate an ultrasonic sensor.
Acoustic imagers work by using an array of microphones to translate sounds into images to detect and visualize air leaks. Instead of needing to get up close to pressurized lines, a handheld acoustic imager can detect and visualize leaks from over 300 feet away. This advanced technology is easy for anyone to use, even if they do not have previous experience with leak detection.
Acoustic imagers in the era of Industry 4.0
In the era of the Industrial Internet of Things (IIoT) and Industry 4.0 technologies, acoustic imagers are a tool that can bring manufacturers further on their journey to connected reliability.
As highly skilled workers retire, manufacturers face the difficult task of staffing specialized roles. Acoustic imagers help fill this skills gap. These tools take a task that previously required specialized knowledge and make it accessible to any employee who simply needs to walk around the facility with a handheld device.
In keeping with Industry 4.0 connectivity, modern acoustic imagers can also send images of visualized air leaks to the cloud for documentation. Advanced algorithms embedded in modern report-writing software can extract data from the images and provide an assessment of the leak, saving time and labor costs.
Data points can also be sent to a computerized maintenance management system (CMMS) to dashboard the information in a central location. This provides up-to-date reports for maintenance teams or decision-makers. Using this information, companies can catalog how often things fail, which assets have the most air leaks and how critical each leak is to uptime and product quality.
Automating leak detection
While handheld acoustic imagers are a popular choice for leak detection, fixed imagers can help capture data on an asset over time and alert teams when something changes.
Fixed acoustic imagers can be set up in a stationary place to focus on problem areas or regions with a lot of critical air or assets. Since they detect noise, they are not limited to just detecting air leaks. They can hear the high-frequency noise of a corona discharge, which can be a sign of degradation in electrical lines. They can also identify mechanical wear in machinery. Fixed imagers can monitor an area 24/7, feeding information back into a computer and streaming the results.
Because a fixed imager always looks at the same region from the same angle, it can tell when there are changes to the noise in an area. Then it can transmit information to a CMMS or another connected system to notify operations, engineering and reliability teams that the area is making more noise than it was previously. Teams can decide if further inspections are needed to identify the root cause of the issue.
In some cases, companies are pairing fixed acoustic imagers with autonomous robots where they can walk an autonomous or controlled route on the factory floor looking for air leaks, even entering clean rooms, tight spaces or dangerous environments where employees may not be able to go.
Not only does this free up employees to do other skilled work, but it improves safety for workers and reduces the risk of contamination for pharmaceuticals or other highly regulated products. The imager is also capable of passing information wirelessly to a CMMS, which can trigger automatic work order generation or alarms when it detects faults.
As a result of this connectivity, companies are seeing the value of leveraging Industry 4.0 technology to simplify and streamline maintenance It is allowing companies to get to the root cause of air leaks faster than they might have even a couple of years ago, and increasing uptime and decreasing costs in the process.
Realizing efficiency gains by detecting and correcting leaks
One real-world example of the impact of correcting compressed air leaks involved a facility with four air compressors. At a plant operated by Genie, a Terex brand, employees used a power logger for a week on its air compressors to track how often they were running, then did a precursory scan of its system with an acoustic imager, correcting only the largest leaks.
After the fixes, it again ran the power logger on its compressors for a week. It found that its fourth compressor no longer turned on at all. It recovered just about 26% of its compressed air capacity and calculated its annual savings at around $49,000. This is just one of many examples from facilities that have started taking air leak detection seriously and realized enormous gains from doing so.
A standard manufacturing facility can use over 30% of its electricity just to generate compressed air2. Detecting leaks keeps energy costs from skyrocketing and reduces unnecessary carbon emissions by ensuring that assets operate as efficiently as possible.
Acoustic imagers have made air leak detection simpler than ever. Facilities that leverage this new technology can recapture their air capacity, reduce their utility costs and ensure their facilities run at peak performance.
