Air and Gas Duct Flow MetersDuct Flow Meters for Air & Gas
Rheotherm flow sensing probes for duct gases are easy to install and provide long-term service with little or no maintenance. The output can be in mass, standard volume or velocity units. Options for hazardous locations (intrinsically safe/explosion-proof) are available. What Can We Measure?
Air and most other non-condensing gases, including corrosive and explosive gases. The stainless steel construction and lack of moving parts make it ideal for rugged industrial environments. Common uses include vent air, stack gas and digester gas. Contact Us
about any application you have.
How Are They Installed?
These are insertion probe flow sensors that install through the pipe or duct wall. Typical line connections are 1” NPT, but flange, hot tap and sanitary fittings are available. The probes can be installed in horizontal or vertical pipes. With some models the electronics are integral to the sensor, and other models have a separate electronics enclosure to install, up to 200 feet from the sensor. Electronics Options
What Is the Turndown Ratio?
How Do They Work?
Typical calibration ranges are 10:1 (options up to 200:1), with good accuracy over the entire range. The sensors cannot be damaged by overranging.
Our insertion flow sensors have a shaft with two stainless steel flow sensing tips. One tip has a heated RTD in it and the other an unheated RTD. The temperature differential between the two RTDs provides the primary flow signal: at high flow rates the differential is lower as flow removes more heat, and at low flow rates the differential is higher, as flow removes less heat. Nothing touches the gas but the metal probe. More on Method of Operation (PDF)
What If There Is Little to No Straight Run Available?
The historically reliable Rheotherm
flow meter for duct flow measurement is available with a revolutionary sensor head which eliminates off-axis error common to other sensors. The system measures true mass flow rate in turbulent ducts and pipes using our standard gas
flow probe design with the Rheovec sensor head added. Rheovec literature (PDF)
How Do I Get A Duct Flow Meter?
Submit your Rheotherm inquiry today to send us the application data to review, or visit our contact us page for telephone, fax and email information.
Insertion Probe Sensor Specifications:
||Duct & pipe gases
||Alloys 276 and 400
|Flow Velocity Limits
||Flange, hot tap, sanitary fitting
||Up to 500ºF (260ºC)
||Depends on fitting
(CL I, Div. 1, Grp BCD)
||1” and larger pipes
|Accuracy (with electronics)
||Up to +/- 1% of reading
Duct flow meter literature (PDF)
Model 210 information (PDF)
Hazardous Locations Options (PDF)
Product Manuals, literature (Resource Center)