Visualizing air leaks with ultrasound
This article introduces ultrasound visualization of air leaks with SONOTEC's SONASCREEN2.
What is SONASCREEN
O SONASCREEN 2 SONOTEC is an industrial portable acoustic camera used to “see” and locate sounds, especially ultrasonic sounds inaudible to the human ear.
What exactly is
- It is an acoustic imaging device that transforms sounds — both in the audible and ultrasonic range — into visual images in real time, showing on screen the location and intensity of sound sources.
- It works like a camera that “sees” sound (technique called acoustic imaging), using a microphone array and advanced processing to generate acoustic maps over visual images.
- It also allows you to listen to recordings through headphones when ultrasonic sounds are converted to audible frequencies.
Main features
- Portable acoustic camera with integrated screen.
- Array of dozens to hundreds of microphones that capture sound up to about 100 kHz.
- Real-time visualization of sound intensity and location.
- visualization + audio: you can see where the sound is happening and hear it at the same time.
- Specialized software for further analysis and reporting.
Why is it useful
SONASCREEN does not detect leaks by thermal or traditional visual imaging, but by sound: fled from ar, gas or leaks produce ultrasonic noises that the equipment identifies and visualizes, even in industrial environments with a lot of background noise.
Visualizing air leaks with ultrasound with SONASCREEN2
To visualize air leaks with SONASCREEN® 2 (SONOTEC acoustic chamber), the idea is to transform invisible ultrasonic sounds (such as those generated by compressed air leaks) in acoustic images visible in real time.
What SONASCREEN does
- The camera uses a microphone array to capture sound in the audible and ultrasonic ranges (up to ~100 kHz).
- Internal software applies acoustic beamforming to locate the source of the sound and generate an acoustic image superimposed on the actual video image.
- Like this, instead of “seeing” the air that is escaping, shows a colored dot or acoustic map on the screen that indicates exactly where the leak is and how intense it is.
How you see air leakage in practice
- Select “Leak” mode / Leakage” (Leak) in the measurement menu.
- You point the camera at the compressed air system or suspicious area.
- The screen shows a colorful acoustic map in real time (typically superimposed on the normal camera image), where the areas with the strongest sounds (leaks) appear as spots/higher intensities.
- While watching, you can hear the ultrasonic sound converted to audio through headphones connected to the camera – this helps confirm location.
- You can capture screenshots or videos with the documentation preview.
Post-processing and documentation
After taking the measurement, SONOTEC provides LeakReport software that allows:
- Analyze measurements offline;
- Create reports with location descriptions and loss estimates;
- Export PDF or tables with results.
Below you can see how SONASCREEN is used 2 to see leaks.
How to estimate the cost of escape
How to estimate the true annual cost of a leak with SONASCREEN 2 da SONOTEC
The camera can estimate the leak flow (L/min). From that, you can calculate the actual annual cost quite accurately.
STEP 1 – Determine the leak flow rate
No mode Leak Detection:
- Enter system pressure (ex: 6 or 8 bar).
- Set the gas type (usually ar).
- Set the distance to the target correctly.
- The equipment shows:
- Estimated flow (ex: 25 L/min)
- Potential cost (if you have a tariff configured)
If you do not have the automatic value, use the flow rate indicated in the main hotspot.
STEP 2 – Convert flow to annual consumption
Base formula:
Typical values
- 1 m³/min of compressed air at 7 bar ≈ 6 a 7 kW
- Typical industrial hours:
- 2 shifts → ~4,000 h/year
- 3 shifts → ~6,000–8,000 h/year
Real example
Suppose:
- Measured Leakage: 20 L/min
- Pressure: 7 bar
- Operation: 6.000 h/type
- Energy cost: 0,18 €/kWh
Convert L/min to m³/min
20 L/min = 0,02 m3/min
Required power
0,02 relative vibrations 6,5 kW ≈ 0,13 kW
Annual consumption
0,13 relative vibrations 6.000 h = 780 kWh/year
Annual cost
780 relative vibrations 0,18 € = 140 € / year
A small leak can cost ~140 €/year.
Now imagine 50 same leaks in a factory.
Quick rule of thumb
In systems at 6–7 bar:
| Leak (L/min) | Approximate annual cost |
| 5 L/min | ~35–50 €/again |
| 10 L/min | ~70–100 €/again |
| 20 L/min | ~140–200 €/again |
| 50 L/min | ~350–500 €/again |
(considering ~6,000 h/year and energy 0,18 €/kWh)
Even more accurate method
For greater rigor:
- Uses the actual kW value of the compressor
- Divide by the actual nominal flow
- Use actual charging hours
- Consider:
- Additional losses (≈10–15%)
- Maintenance costs
- Impact on redundancy
How to calculate the ROI of a leak detection campaign (compressed air)
Not SONASCREEN 2 da SONOTEC, or ROI (Return on Investment) shows how much money the campaign returns compared to the cost of the campaign.
ROI Formula
Calculate Annual Savings
Sum of leaks repaired:
Example:
| No. of leaks | Average annual cost | Total |
| 30 | 180 €/again | 5.400 €/again |
Estimated annual savings: 5.400 €
Calculate campaign cost
Includes:
- Inspection hours (technical)
- Repair hours
- Reports / software
- Power stopped (if applicable)
- Equipment cost (was bought)
Example:
| Item | Valor |
| 2 technical days | 800 € |
| Repairs | 1.200 € |
| Total campaign | 2.000 € |
ROI calculation
It means the investment returns 1,7 times the amount invested in the first year.
Payback (Turnaround time)
About 4–5 months to recover investment.
Actual typical values in the industry
- Industrial systems have 20–35% leakage losses
- Common ROI: 100% a 500% in the first year
- Payback típico: 3 a 6 months
