Insertion Thermal Flow Meters

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Accurate Gas Flow Measurement for Industrial Applications

Capitalizing on more than 40 years of experience, our insertion thermal gas mass flow meters have been deemed North America's #1 selling immersible flow meter (Flow Research, Boston, MA). Our immersible thermal meters range from our highest-accuracy QuadraTherm 640i/780i to our more traditional, but also very accurate, 600 Series. Both our inline and insertion flow meters are ideal for highly accurate gas mass flow measurement in both heavy and light industrial applications. View related products and videos below.

Boiler MACT Certified
Sierra’s insertion thermal mass flow meters are also ideal for compliance for Boiler MACT  regulations for inlet fuel measurement for area source boilers (40 CFR 63, subpart JJJJJJ) and for major source boilers (40 CFR 63, subpart DDDDD). Learn More

Our proven immersible thermal gas mass flow meters:

  • Offer direct mass flow, immune to changes in temperature and pressure
  • Offer rugged and reliable industrial gas and air mass flow measurement
  • Are ideal for small pipes, as well as 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
  • Allow customers to create and upload new gases as their gas composition changes with new qMix gas mixing software Learn More

Want the best in gas flow measurement? All of our insertion-type gas flow meters feature the long-term stability of our patented no-drift DrySense swaged velocity sensor technology and are backed by a lifetime warranty. As the name implies, Sierra’s swaged velocity sensor is the only thermal sensor in the world that is truly “dry,” using no organic or cement fillers that crack and shift causing drift over time. For easy system automation systems automation and control, we offer the following digital communications solutions: HART, Modbus RTU, and Profibus DP.

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