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Blog: Let's Talk Flow

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Worlds Highest Accuracy Thermal Mass Flow Meters

QuadraTherm 640i/780i

The QuadraTherm 780i inline version achieves accuracy of +/- 0.5% of reading, making it the most accurate thermal mass flow meter in the world. Before QuadraTherm, this level of accuracy was never thought possible by any thermal dispersion mass air/gas flow meter manufacturer.

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QuadraTherm is the first four-sensor thermal mass air flow meter ever designed—three precision platinum temperature sensors and one patented DrySense™ mass flow velocity sensor backed by a lifetime warranty.

QuadraTherm benefits include:

  • Change gas with Dial-A-Gas® technology
  • Change pipe size with Dial-A-Pipe® technology in the field 
  • Multi-gas flow totalizer totalizes up to four gases with one device and software package
  • qMix™ gas mixing software creates custom gas mixtures in the field to compensate for gas compositional changes—all without returning the meter to the factory for recalibration; Download Flare Gas Mass Measuring Tech Note
  • Boiler MACT certified for area source boilers (40 CFR 63, subpart JJJJJJ) and for major source boilers (40 CFR 63, subpart DDDDD) Learn More. 
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QuadraTherm 640i
QuadraTherm® 640i

Industry's Most Accurate Air / Gas Thermal Insertion Mass Flow Meters

  • Achieve high accuracy +/- 0.75% of reading
  • Eliminate drift with patented DrySense™ sensor
  • Validate in the field for easy in-situ calibration
  • Use qMix software to easily change gas composition in the field and retain accuracy Download Flare Gas Mass Measuring Tech Note
  • Backed by lifetime sensor warranty
  • Boiler MACT certified for area source boilers (40 CFR 63, subpart JJJJJJ) and for major source boilers (40 CFR 63, subpart DDDDD) Learn more > 
  • Part of Sierra's Big-3 iSeries family of flow meter technologies Learn more >
  • Meet EPA rule 40 CFR 63 for flare gas measurement at ultra-low flows down sfps (0.03 smps) with QuadraTherm® qMix RealTime Flare Measurement System (FMS)
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QuadraTherm<sup>®</sup> 780i Inline Mass Flow Meter.
QuadraTherm® 780i

Highest Air/Gas Mass Flow Measurement Accuracy in Industry

  • Achieve the highest accuracy +/- 0.5% of reading
  • Eliminate drift with DrySense sensor
  • Reduce straight-run requirements with built-in flow conditioning
  • Needs only 1-diameter up and zero downstream diameters
  • Validate in the field for easy in-situ calibration
  • Backed by lifetime sensor warranty
  • Boiler MACT certified for area source boilers (40 CFR 63, subpart JJJJJJ) and for major source boilers (40 CFR 63, subpart DDDDD), Learn more > 
  • Part of Sierra's Big-3 iSeries family of flow meter technologies, Learn more >
  • Meet EPA rule 40 CFR 63 for flare gas measurement at ultra-low flows down sfps (0.03 smps) with QuadraTherm® qMix RealTime Flare Measurement System (FMS)
Get A Quote Learn More
qMix Gas Mixing Feature
qMix Gas Mixing Feature

Field-Update For Gas Composition Changes

  • Powerful, gas mixing software to create custom gas mixtures in the field
  • Per meter license gives unlimited custom gas mixtures and uploads per meter serial number
  • Maintain flow meter accuracy if gas composition changes
  • No need to send unit back to the factory if gas composition changes
  • Avoid costly recalibration
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QuadraTherm<sup>®</sup> qMix RealTime Flare Measurement System
Measure Flare Gas in Real Time

QuadraTherm® qMix RealTime
Flare Measurement System

  • Meet EPA rule 40 CFR 63-measure flare gas down to 0.1 sfps (0.03 smps) where ultrasonic flow meters can't operate
  • Handles upset conditions at ultra-high flows with wide 1000:1 turndown
  • Easy to install with current ultrasonic flow meters-no process shutdown
  • Use qMix RealTime App to connect, read, and update new flare gas composition from a GC-real time, no recalibration needed
  • Set update frequency by time or by percentage change in the gas composition
  • Get flow and composition trend analysis, flow alarming and triggers
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