Flow Measurement:

Air|Gases|Transparent liquids|Vacuum|Water

Product Datasheet

See-Flo® Meters indicate flow rate and permit visual inspection of water, air or other transparent fluids. For general purpose industrial service, See-Flo® meters handle a wide range of process fluids in vertical or horizontal piping runs. The wedge shape of the meter housing makes See-Flo® practically self-cleaning. Where periodic maintenance might be necessary, the tempered glass window is easily removed and replaced.

  • Instantaneous flow rate measurement.
  • Observe fluid conditions for color, clarity and flow.
  • Use in horizontal or vertical piping systems.
  • Individually calibrated for fluid and operating conditions.
  • User selectable 10:1 turndown flow ranges. (See Meter Rangeability Sizing Tables)
  • User selectable units of measure including dual units of measure.
  • No floats to get stuck, tubes to break or dynamic seals to leak.
  • Low pressure loss.
  • Simple design with few parts for long service life.

flex-flo-principal-operationsArmor-FloTM meters are variable area flow rate meters (“rotameter”). See-Flo® meters are variable area flow rate meters (“rotameter”). The internal volume of the housing enlarges from the inlet to the outlet. The primary element is a tempered alloy vane with one end affixed to the apex of the meter housing. As the flow rate changes, the vane is flexed in direct proportion.

The 1/2“, 3/4“, and 1” connections typically have female threaded ends. Sizes 1 1/4” through 12″ utilize an integral by-pass housing enables larger connection sizes in the format of a spool with a consistent 12″ end to end dimension. In addition, it permits a wide variety of connection types which include threaded, flanged, grooved ends and tri-clamp.


Accuracy: ±2% full scale

Repeatability: ±1% full scale

Direct reading
Resolution: Maximum-30 division/Minimum-15 divisions

Rangeability: 10 to 1 turndown

Materials of Construction:

  • Housing: Aluminum,brass, 70/30 copper/nickel, 316 stainless steel
  • Shunt: As housing or carbon steel
  • Window: Tempered glass or polycarbonate
  • Vane: Cobalt/chromium/nickel alloy with Teflon ® encapsulated magnet
  • “O” rings: buna-n, ethylene propylene, Viton® or perfluoroelastomer

Piping Connections:

  • 1⁄2″ to 1″ NPT Female
  • 1 1⁄4″ to 4″ NPT male
  • 1 1⁄2″ to 3″ Tri-clamp
  • 1 1⁄4″ to 6″ Grooved
  • 1 1⁄4″ to 6″ Beveled 1⁄2″ to 8″ 150# /300# RF/FF ANSI Flanges (carbon stl)
  • 1⁄2″ to 8″ 150# RF ANSI Flanges (stainless stl)
  • 1⁄2″ to 6″ 150# RF ANSI Flanges (aluminum)
  • 1⁄2″ to 6″ 150# FF ANSI Flanges (brass)
  • 15 to 25 mm DIN 2999/BS21/ISO R7 Female threaded
  • 15 to 150 mm DIN PN 10 Flanges (316 stainless stl & carbon stl)



Pressure Limits: 200 psig (13.8 bar)

  • Temperature Limits:
    -23 to 85°C (-10 to 185°F) with polycarbonate window.
    -23 to 121°C (-10 to 250°F) with buna-n o-ring.
    -23 to 121°C (-10 to 250°F) with Viton®, ethylene propylene or perfluoroelastomer o-ring

ERDCO reserves the right to alter design and/or specifications without notice. Viton® is a registered trademark of E.I. duPont de Nemours and Co.