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Employee with a Sense for Compressed Air

How the "Sonaphone" helps find undiscovered leaks in the Wolfsburg press shop.

Tüftler: Olaf Thor an seinem Arbeitsplatz im Technologiecenter des Presswerks.

Leaks in compressed air lines are a problem. Maintenance worker Olaf Thor is a tinkerer, and loves solving problems. Now, as a team member of the Press Shop’s technology center in Wolfsburg, he has ensured that leaks can be detected using a digital ultrasound device.

The problem

Compressed air is an expensive resource and plays an important role in the plant: A large drop in pressure is not only wasteful, but can even put the production process at risk. All the more annoying if a significant portion escapes unnoticed via hairline cracks in weld seams, valves, or pipes connections.
These weak points usually can’t be spotted with the naked eye. Sometimes they can be felt or heard, provided that the environment isn’t too noisy to hear the hiss of escaping air. But that is almost never the case in the press shop. The result: A loss that amounted to around 1,200 liters of compressed air per minute in the second half of 2018 alone. And that’s just in one part of the Wolfsburg press shop, Press Shop 1.

The solution

The team at the technology center did some real detective work, before hitting upon a digital ultrasound device. The team quickly realized: This could be used to detect leaking air. “The Sonaphone can also be used to measure noise from a flowing current,” explains Olaf Thor. “Just like escaping air, these sounds are hardly perceptible to the human ear.” This is because the escaping air makes a sound that is in the ultrasonic range. However, the Sonaphone is able to detect these sound waves.

Measurement: Leaking air can be detected with a digital ultrasound device.

The device, which resembles a large smartphone, is connected via cable to a sound sensor, hardly bigger than an ordinary ballpen. A probe then localizes the source of the noise and measures the amount of leaking air in seconds.
The device then generates a report. An integrated camera makes it possible to clearly label the leak – a great help to the repair team responsible for repairing the damage.

Heike Ripke, Head of Maintenance, Mechanics and Hydraulics in the Press Shop, says: “The Sonaphone detects even the smallest leaks, where human hearing wouldn’t stand a chance. This is how innovative technologies help set up our press shop for the long-term future.” Works Councilor Andreas Hoppenbrink says: “This great idea is another fantastic example of how the employees themselves are the best experts. There is so much knowledge and creativity in the workforce of the press shop and other departments that we can achieve a lot more improvements.”

"The Sonaphone detects even the smallest leaks, where human hearing wouldn’t stand a chance"

Heike Ripke, Head of Maintenance

"This great idea is another fantastic example of how the employees themselves are the best experts"

Andreas Hoppenbrink, Works Councilor