The Evolution of Non-Invasive Clamp-On Gas Flow Measurement

Katronic Technologies, leading manufacturer of non-invasive, clamp-on flow instrumentation, is very proud to announce its newest development, the KATflow 180 clamp-on meter for gases.

The ATEX-approved KATflow 180 takes non-invasive, clamp-on measurement into new areas with the ability to measure gaseous flow at low pressures and even in metal pipes – something that was previously virtually impossible to achieve.

Clamp-on measurement of gas has, typically, required minimum pressures of around 5 bar and has been limited to plastic pipes and ‘ideal’ installations. The KATflow 180 can be used where the pressure is well below that ‘minimum’, even down to atmospheric pressure. Not only that, but Katronic’s ‘Lamb wave’ technology has made accurate measurement possible even in metal pipes, including steel.

A gaseous medium dampens an ultrasonic signal far more than a liquid, making non-invasive flow measurement of gases far more difficult. The effect reduces as pressure increases, hence the 5 bar lower pressure limit at which conventional transit time measurements using ‘shear waves’ can be made. Katronic has made an important breakthrough, developing a new approach to activate (‘excite’) the ultrasonic transducers. Katronic’s Lamb wave transducers are excited at the resonant frequency of the pipe material, allowing the pipe itself to become part of the sensing apparatus. The pipe wall acts as both emitter and receiver of the ultrasonic pulses, multiplying the effective transducer area for a higher signal strength and a better signal/noise ratio.

The KATflow 180 clamp-on meter for gases

A stronger signal means that the KATflow 180 is better able to compensate for the attenuation of the gas, and Katronic have developed more advanced signal processing techniques to analyse the measured data and deliver an accurate measurement.

The KATflow 180 is able to measure in pipes from 25 mm to 1.5 m diameter, with flow rates of 0.1 m/s to 75 m/s and pressures of 1 bar up to unlimited maximum. It is designed to be capable of being mounted permanently in an ATEX Zone 1 or 2 hazardous area, with a robust housing and non- intrusive programming.

Commenting on the launch, Andrew Sutton, MD of Katronic, said, ‘The KATflow 180 is a real step forward. We have taken a new view of an old problem and developed a completely novel approach. I’m very proud of the R&D team, this has been a major project and they have achieved something that has never been done before.’

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Providing reliable flow measurements to satisfied customers since 1996. Katronic's excellent reputation has been built on offering accurate and intuitive clamp-on flow meters supported by market-leading customer service and technical support. Katronic was established in the UK in 1996 as a distributor of process measurement instrumentation with a ...

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