Sierra Instruments

The Mass Flow Company

Sierra's Flow Measurement and Control Division is known for design and manufacture of innovative high-performance fluid flow measurement and control instrumentation for nearly any gas, liquid and steam application spanning across global industries as diverse as scientific research, semiconductor, wastewater treatment, iron and steel, clean energy, aerospace and biotech to name a few.

Sierra's Flow Measurement and Control Division designs and manufactures high precision capillary-sensor based Mass Flow Meters and Controllers for gas flow in applications.  Sierra also designs and manufactures Immersible Thermal Mass, Transit-Time Ultrasonic, Vortex Shedding and Multivariable flow instruments in both standard and customized versions for applications in industrial and hazardous environments.

Sierra's technologies precisely measure and/or control very low flows of gas down to less than 1 sccm full scale as well as extremely high flows of gas, liquid, and steam.

Sierra Instruments
Sierra Instruments Products

Sierra Instruments Products

Product Line

  • Gas Mass Flow Controllers & Meters
  • Gas Flow Calibration Systems
  • Thermal Mass Flow Meters
  • Thermal Flow & Level Switches
  • Vortex Mass & Volumetric Flow Meters
  • Ultrasonic Flow Meters (Transit-Time)
  • Digital Communications Solutions
  • Software Solutions
  • Digital Control / Readout Power Supplies
  • Flow Conditioning Solutions
  • Liquid Flow Meters
  • Natural Gas Flow Meters
  • Steam Flow Meters
  • Fuel Flow Meters

Sierra's Powerful Big-3™ Flow Technologies

Flow Energy Measurement With Thermal, Vortex, Ultrasonic

Do you want to know the perfect solution to any fluid flow application in any facility around the world?

Matt Olin, CEO of Sierra, shares the complete flow energy measurement and management solution: The Big-3™ iSeries of products, which offer Thermal, Vortex, and Ultrasonic technology solutions. The powerful iSeries family of products is designed, built and calibrated by Sierra in Monterey, CA, USA.

Learn how these world-class products share sensor technology and have apps that empower YOU and your process.


  • Natural Gas Measurement & Control
  • Mass Flow Measurement & Control
  • Digital Flowmeters & Controllers
  • Compressed Air Measurement & Control
  • Flare Gas Measurement
  • Waste Water Treatment
  • Liquid Flow Measurement
  • Steam Flow Measurement
  • Fuel Flow Measurement
  • Argon Mass Flow Meters
  • Carbon Dioxide Mass Flow Meters
  • Nitrogen Mass Flow Meters
  • Gas Mixing & Blending
  • Ultra Low Pressure Drop MFC
  • High Pressure Flow
  • Low Flow Control (Down to 0.1 sccm)
  • High Flow Control (Gas flow to 1000 slpm)
  • Large Pipes & Ducts, Hot Tapping, Purging

Application Example

Superior Natural Gas Measurement & Control

Precise measurement of natural gas requires high accuracy, low pressure drop and direct mass flow reading—all the hallmarks of Sierra’s immersible thermal, mass vortex and thermal mass flow controllers. Sierra's mass flow controllers are ideal for natural gas flow measurement with 100:1 turndown and no moving parts, providing a robust MFC solution. Sierra's natural gas flow measurement instruments can also handle liquefied natural gas (LNG) via our cryogenic mass vortex meters.

Measuring Natural Gas More Efficiently

High quality natural gas measurement increases efficiency in boiler/burner control, fuel-to-air ratio, and custody transfer applications. The bottom line is the more accurate your natural gas measurements, the more money you will save in natural gas costs.

With over 25,000 units sold for natural gas measurement across the applications below, Sierra has a proven full line of natural gas measurement products from immersible thermal, mass vortex and thermal mass flow controllers, depending on your application. To effectively measure natural gas, our flow meters are easy to install and retrofit into existing piping, and have greenhouse gas certification.

Sierra's digital communications solutions for use in conjunction with mass flow controllers for measuring natural gas also offer engineers and systems integrators full industrial system integration and networking capability with Sierra's industrial flow meters.

How flow meters help conserve energy and save on your natural gas bill

Image Credit: Sierra Instruments Blog