The CPA Flow Nozzle is the simplest dP measurement nozzle design offered by Canada Pipeline Accessories. The completed part consists of only the converging inlet contour and the cylindrical throat. Several variations of the CPA Flow Nozzle are available, including the long radius, ISA 1932, and cylindrical inlet nozzle.

The pressure measurements will be taken from taps located on the meter run piping, a specific distance from the nozzle. CPA provides guidelines on where to install the meter run pipe taps and what size they must be. However, the meter run piping and the taps themselves are not included with the CPA Flow Nozzle, and must be supplied separately.

CPA Flow Nozzle Basic

All CPA Flow Nozzles are custom designed per your specific conditions, whether liquid, gas, or steam. The beta ratio can by specified directly, or CPA can calculate a beta ratio for you using an approved standard such as ISO 5167, ASME 3M, and ASME PTC-6. For a customized beta ratio calculation, CPA requires detailed process information including fluid density, flow rate, and desired differential pressure.

Like all CPA products, the Flow Nozzle is available in a wide range of materials and can be customized to suit your specific needs. The CPA Flow Nozzle is designed to be installed between two raised face, full face, or RTJ flanges. It can also be butt welded between two pipe spools. A portion of the nozzle will extend into the section of pipe located immediately downstream of the flange or weld point.

Flow Nozzles vs Orifice Plates

The CPA Flow Nozzle is intended for subsonic flows only and should not be used in critical choked flow conditions. For flow measurement in sonic conditions, CPA recommends use of a sonic nozzle.

For further information, do not hesitate to contact our experienced sales representatives, who will be able to help you choose the correct product for your specific needs.

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  • Very simple design, no moving parts, no maintenance requirements, and low fouling rate.
  • Utilizes flange pressure taps or pressure taps installed directly onto the pipe.
  • Available for installation between raised face flanges, or for welded applications.
  • Custom manufactured for your exact process conditions.
  • Available calibration services through one of our test lab partners.
  • Available in a large range of sizes, and materials.
  • Manufactured to recognized industry standards such as ASME/ANSI/ISO.