Correlation-based flow measurement for hot, heavily dust-laden gases, free of drift and calibration
The McON Air system measures the time of flight of the signal patterns created by the particles carried in the gas itself. Because it relies on a time measurement, the reading is accurate and stable over the whole life of the equipment, even at 1000 °C and with 2500 g/m³ of dust.
Advantages
Measures where other principles fail
Neither dust nor temperature degrades the signal: the system works with dust loads up to 2500 g/m³ and gases up to 1000 °C, with no purging and no periodic cleaning.
No drift, no recalibration, no K-factors
The direct time-of-flight measurement needs no correction factors and no pressure or temperature compensation, and the plausibility of the raw signals is supervised continuously.
Installation without stopping the plant
The sensors are mounted via flange and support hot tapping, so the installation does not force a process shutdown and requires no subsequent calibration of the sensors.
Turn-down ratio of 25:1
With a ±2% accuracy and a turn-down ratio of up to 25, the same installation covers everything from minimum working flow to full load.
Immediate payback
By eliminating maintenance, purging and recalibration, the usual return on investment is under 3 months, and the digital online measurement feeds the process control directly.
Applications
- Cement plants: tertiary air, downcomer, vertical raw mill, clinker cooler, bypass and waste heat recovery.
- Steelworks: electric arc furnace off-gas.
- Power stations: primary and secondary air, flue gas and unburned carbon.
- Waste-to-energy plants and emission monitoring, with the accurate measurement of the total stack flow.
About the product
The Compact version is the fixed single-channel solution: two probes in the duct and an evaluation unit with 4-20 mA outputs for velocity and volume flow. For safety loops there is the SIL variant, available as a SIL 2 version, and for measurement campaigns the Portable version brings the same principle to a mobile kit with rugged cases, CSV data logging on SD card, an additional 4-20 mA output and probes of different lengths.
The instantaneous reading in m/s is obtained as soon as the probes are connected, with no prior calibration. Available accessories: probes of different lengths for each duct diameter, SIL 2 certified version and complete portable kit.
Technical specifications
| Measuring principle | Correlation: time of flight of signal patterns |
| Gas temperature | Up to 1000 °C |
| Dust load | Up to 2500 g/m³ |
| Accuracy | ±2% |
| Turn-down ratio | Up to 25:1 |
| Outputs | 4-20 mA for velocity (m/s) and volume flow (m³/h) |
| Calibration and drift | No calibration, no purging, no K-factors |
| Versions | Compact (fixed single channel), SIL (SIL 2) and Portable |
Frequently asked questions
How can it measure with so much dust?
Because the particles themselves generate the signal patterns being correlated: the more heavily laden the gas, the clearer the signature the system measures.
Does it need recalibration over time?
No. Time-of-flight is a direct physical measurement, free of drift, and the system continuously checks the plausibility of the signals.
Is it suitable for emission monitoring?
Yes. It provides the accurate total stack flow measurement required for calculating mass emissions.
Can it be installed without stopping the process?
Yes. The flange mounting supports hot tapping, keeping full plant availability during installation.
Is there a version for spot measurements?
Yes. The Portable version offers the same principle in a mobile kit with SD card logging and a 4-20 mA output for connection to the plant control system.
