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Thermal Mass Flow Meters
Advanced Technology For Precision Measurement of Gas Mass Flow Rate
North America's #1 selling thermal mass flow meter (2009 Flow Research), our heavy-industrial thermal mass flow meters are designed for the most demanding industrial gas mass and air mass flow measurement applications. We manufacture a wide variety of inline and insertion thermal mass flow meters for precision measurement of gas mass flow rate in industrial applications. Our thermal meters range from our highest performance QuadraTherm four-sensor design to our more traditional, and also very accurate, two-sensor instruments.
For customers who enjoy the many benefits of thermal technology—wide turndown ratio, very low pressure drop, no moving parts, application flexibility, and a direct gas mass flow rate measurement—now you get extreme precision with percent of reading accuracy as part of the total QuadraTherm package.
All of our thermal meters feature the long-term stability of our patented no-drift DrySense velocity sensor technology backed by a lifetime warranty. As the name implies, Sierra’s velocity sensor is the only thermal sensor in the world that is truly “Dry”. Our proprietary swaging process eliminates all air gaps between the heated velocity sensor and the tubular probe without the need for any "Wet" potting compounds such as epoxy, ceramic cement, thermal grease, or alumina powder. These wet velocity sensors have increased skin resistance, decreased sensitivity, and most importantly age and crack over time causing sensor drift and reduced long term accuracy.
The result of DrySense is maximum sensitivity, reproducibility, immunity to cracking and shifting over time, and ultimately greatly improved accuracy. Sierra also manufactures a range of Light-Industrial thermal mass flow meters.
For easy systems integration, we offer the following digital communications solutions: HART, Modbus RTU, and Profibus DP. View all of our digital communications solutions offering turnkey solutions for industrial systems automation and control.
» QuadraTherm Selection Chart
» Traditional Thermal Selection Chart
QuadraTherm (Advanced Four-Sensor Design)
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 QuadraTherm® 780i Inline Mass Flow MeterBest Accuracy: ± 0.5% of reading above 50% of the full scale; built-in flow conditioning; multivariable outputs, flow range up to 60,000 sfpm (305 smps), qTherm™ Dial-A-Gas®, Dial-A-Pipe, Hazardous Area approvals, Digital Communications (pending)
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QuadraTherm® 640i Insertion Mass Flow Meter Accuracy: ± 0.75% of reading above 50% of the full scale; 3/4" (19.1 mm) insertion probe up to 72" (2m) long, multivariable outputs, flow range up to 60,000 sfpm (305 smps), qTherm™ Dial-A-Gas®, Dial-A-Pipe, Hazardous Area approvals, Digital Communications (pending)
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Traditional Thermal (Two-Sensor Design)
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SteelMass™ 640S Insertion Mass Flow Meter Accuracy: ± 1.0% of reading +0.5% full scale; Accurate and repeatable, this product is a rugged and reliable mass flow measurement workhorse in heavy industrial applications, flow range is up to 20,000 sfpm with standard accuracy. Digital communications solutions include: HART, Modbus RTU, and Profibus DP.
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FlatTrak™ 780S In-line Mass Flow Meter with Flow Conditioning Accuracy: ± 1.0% of reading +0.5% full scale; provides repeatable, rugged, and reliable performance and built-in flow conditioning, flow range is up to 20,000 sfpm with standard accuracy. Digital communications solutions include: HART, Modbus RTU, and Profibus DP.   |
Specialty Application Thermal Mass Flow Meters
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Ultra High Purity 780S UHP In-line Mass Flow Meter with Flow Conditioning This is the industry choice for gas distribution in ultra-clean processes. This product features 316L electropolished tubing with 7-10 Ra or 20-25 Ra interior finishes.Digital communications solutions include: HART, Modbus RTU, and Profibus DP. |
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MultiTrak™ 670S High-Performance Multi-Point Flow Meter for Large Ducts and Stacks Sierra's MultiTrak™ 670S is an advanced state-of-the-art instrument for measuring mass flow rates in very large ducts or stacks that have non-uniform velocity profiles, high turn-down requirements, dirty gas streams, wide temperature ranges and fast velocity and temperature changes. |
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ChlorineTrak™ 760S In-line Mass Flow Meter A special version of the 780S, the ChlorineTrak 760S is specifically designed as a cost-effective mass-flow measurement solution for chlorine injection processes found in typical waste-water treatment applications. Product accuracy is +/- 5% of full scale, and the flow range is up to 300 scfm chlorine in a 4” Kynar® flow body. Digital communications solutions include: HART, Modbus RTU, and Profibus DP. |
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FlowTrak™ Dual-Plate Flow Conditioning Element As used in our 780i and 780S products, flow conditioning elements represent an economical solution to problems associated with monitoring flow installations where long, straight runs of piping are not available. |
