SmartMeasurement Thermal Mass Flow Meters
Thermal Mass Flow Meters
The monitoring and measurement of gases in manufacturing and process plants from chemical, to oil/gas, wastewater, etc. is essential including safety, process control, product quality, production efficiency, environmental compliance and costs. If measurement of gases is inaccurate or inconsistent, some potential outcomes include serious accidents, emergency shutdowns, unplanned maintenance, production slowdowns or cost overruns.
There are six to eight viable gas flow measurement technologies available today most of these technologies measuring volume such as turbine meters ALTM, Vortex ALVT, variable Area ALVAMT and others. These flow technologies do measure gas; however, the volume of gas can change greatly with a slight change in either pressure and temperature, making a calibrated volumetric flowmeter highly inaccurate. Therefore, SmartMeasurementTM recommends only the use of direct mass flow measurement which automatically compensates for changes of either pressure or temperature or both. Both volumetric and mass flow has their advantage and disadvantages but they don’t compete with each other as mass is completely different than volume. Please go to mass flowmeters.
Advantages of Thermal Flow Meters
The thermal mass flow meter has been used to improve plant efficiency in many industries including industrial compressed air, pharma, biotech, and food and beverage, etc. Thermal mass flow meters measure the mass flow based on heat transfer from a heated element. The only other meter that measures mass ow directly is the Coriolis meter. Both the thermal meter and Coriolis do not require additional pressure and temperature correction. The thermal meter provides acceptable accuracy and excellent repeatability without the substantial upfront cost of the Coriolis. Additionally, the thermal mass flow meter is easy-to-installed and has negligible pressure drop. Thermal mass ow meters have excellent low-ow sensitivity and can measure some gas flows that the Coriolis meter cannot because the gas density may be too low. Coriolis flow meters all though a much as 10 times better accuracy than thermal meters are mainly used in liquids or high-pressure gas applications. For pressures less than 500 psi, low flows and no pressure drop thermal meters proves greater advantages.
SmartMeasurement ATMF series
The most SmartMeasurementTM ATMF series of insertion and inline thermal flow meters, or thermal dispersion flow meters utilizes constant temperature difference method of measuring Gas Mass Flow Rate. It contains two reference grade platinum RTD sensors clad in a protective 316 SS sheath. Features direct Mass Flow for gases, wide rangeability, low pressure drops, very low-end sensitivity, and no moving parts. The ATMF series is microprocessor based, does not have any potentiometers. Electronics can be Integral Style, or remote mount with rugged windowed dual compartment enclosure with local or remote display. Four models available from the low-cost blind meters to the more exotic featured SP models. Calibration Self Check: Flow Meter has built in diagnostics – a display of the calibration milliwatts (mw) can be used to check the sensor’s operation by being compared to the original reported “zero flow” value noted on meter’s Certificate of Conformance (last few lines) and metallic tag. This convenient in-situ field diagnostic procedure verifies that the original factory calibration hasn’t drifted, shifted, or changed. This “Sensor Functionality and Zero Self Check” also verifies that the sensor is free from contamination, even without inspection.