Thermal mass flow meter for compressed air and gases from DN 15 to DN 700, with totaliser

Flow meter based on thermal mass flow measurement, intended for metering the consumption of compressed air and gases in pipes from DN 15 to DN 700. It is suitable for air, nitrogen, carbon dioxide, oxygen and other non-corrosive, non-flammable gases. Each instrument is factory-calibrated for its application at 7 bar absolute (DN 15…DN 50) or 9 bar absolute (DN 65…DN 700): this keeps the actual velocity in the pipe low even at high flow rates, giving a more stable flow profile and better repeatability and accuracy than conventional calibration at normal pressure.

Features

• Measuring ranges from 0.32…63 Nm³/h up to 263.4…263,350 Nm³/h (air)
• G ½…G 2 or ½…2" NPT measuring section with ball valve; R ½ threaded connection for insertion into DN 65…DN 700 pipes
• Stainless steel, brass ball valve
• Maximum pressure 16 bar, maximum temperature 80 °C
• Accuracy ±2.5 % of reading + 0.15 % of full scale
• Two outputs programmable as analogue, switching or pulse for mass, volume, temperature and consumption
• Built-in totaliser, value retained after a power failure
• Optional digital indicator

Operating principle

The sensing element is a hot-film sensor manufactured using thin-film technology: the gas flowing over it removes heat according to the mass flow rate. This type of sensor offers fast response, high reliability and excellent long-term stability.

Applications

Consumption metering and cost allocation for compressed air, nitrogen, CO2, oxygen and other non-flammable technical gases in industrial distribution networks.