With the largest staff of trained hydraulic engineers anywhere, Primary Flow Signal offers total engineering support from design through installation and beyond.

As the industry leader in flow meters, with over two decades of experience, our integrated team of specialists provide engineering analysis of your existing flow measurement system and develop reliable solutions for today and the future.

We continue to support our installations where others leave off, providing prompt and reliable responses to your technical questions from our dedicated field and lab engineers.

Primary Flow Signal, Inc. (PFS) employs the industry’s largest full-time staff of engineers and technical experts in differential producer type flow metering to provide hydraulic analysis for a variety of systems, including those handling oil & gas, water, wastewater, and steam. 

As a vertically integrated, full service metering supplier, our team's expert analysis informs the planning, design, manufacture, and rehabilitation of flow systems that we deliver to our customers. An unwavering commitment to quality and unparalleled proprietary expertise translates directly into the leading accuracy and reliability of our systems.


  • PFS will analyze your system and provide all the right parts necessary for each installation.
  • Our controller is designed to meet your requirements. Others will attempt to force you to meet their controller's performance.
  • The complete Rate-of-Flow Controller is assembled and tested prior to shipment to the job site. This reduces the risks inherent in relying on separate parties for the success of the installation.
  • Full five (5) year warranty on the complete controller with an additional 20 years on the HVT primary.

Although Primary Flow Signal recommends replacing aging Venturi flow primaries with new high-performing Halmi Venturi flow meters, organizational budgets may not support unit replacement.

To meet such needs, Primary Flow Signal developed a Venturi Meter Rehabilitation Program to rehabilitate and recalibrate existing flow meters, restoring meters to original operating specifications.

Primary Flow Signal’s Venturi Meter Rehabilitation Program remedies typical problems such as:

  • Plugging of impulse taps or annular chambers
  • Plating, corrosion, or scaling of interior surfaces
  • Mercury-filled instrumentation or contaminated flow primaries

PFS will customize a Venturi rehabilitation plan specific to your needs. Our services include:

  • On-site analysis and rehabilitation
  • Factory rehabilitation at a Primary Flow Signal, Inc. facility
  • Independent lab calibration from leading academic and commercial facilities
  • NIST-traceable calibration at the Primary Flow Signal in-house calibration facility
  • Recalibration of products and primaries built by other manufacturers

Benefits of rehabilitation include:

  • Lower cost versus the purchase of a new meter
  • Conserves original piping, structures, and meter
  • Improved accuracy, range, and design
  • More durable and reliable compared to alternative technologies

Primary Flow Signal provides comprehensive one-stop specialized service for new and existing flow meters:

Venturi Rehabilitation: We offer on-site and factory rehabilitation for any type of Venturi meter, restoring meters to original, high performance functional parameters

Hydraulic Analysis: Our specialized in-house teams provide custom hydraulic analysis to ensure optimum operation

Engineering Support: Engineers specialized in new and existing flow primaries provide support, ensuring accuracy and longevity


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SADR City - Flow Primary


Expert Engineering Analysis for Today and the Future