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Bronze sight flow indicator with dual tempered glass windows and rotor, 1/2 inch FNPT connections

Dwyer Instruments Inc.

Dwyer Instruments SFI-300-1/2 Sight Flow Indicator 1/2" Bronze

SKU CH-W0NJ-7WK8D

Bronze sight flow indicator with rotor and dual tempered-glass windows for 1/2" FNPT lines up to 125 psig and 200 °F

  • MaterialBronze
  • Visual flow confirmation via dual tempered-glass windows
  • Rotor indicator shows movement at a glance
  • Bronze body withstands 125 psig operating pressure
  • Buna-N seals handle 32 to 200 °F media temps
  • Compact 4.063 in length fits tight piping runs

1/2" Bronze Sight Flow Indicator

The Dwyer Instruments SFI-300-1/2 is a window sight flow indicator with a bronze body and 1/2 inch FNPT connections. It uses a rotor impeller visible through two tempered glass windows to confirm fluid movement. The unit measures 4.063 inches in length and handles flow in horizontal or vertical directions.

Installers verifying flow in bronze piping

This indicator suits technicians who need a visual check of liquid flow in lines rated for 125 psig and media temperatures between 32 and 200 degrees Fahrenheit. Buna-N seals limit compatibility with aggressive chemicals or steam service. Buyers needing larger connections, higher pressure ratings or different seal materials should look elsewhere.

125 psig maximum operating pressure

The 125 psig pressure ceiling is the primary limit that decides if this indicator fits the system. Exceeding this rating risks seal failure and glass damage. Confirm the line pressure stays at or below this figure before specifying the SFI-300-1/2.

Highlights

  • Visual flow confirmation via dual tempered-glass windows
  • Rotor indicator shows movement at a glance
  • Bronze body withstands 125 psig operating pressure
  • Buna-N seals handle 32 to 200 °F media temps
  • Compact 4.063 in length fits tight piping runs

Specifications

MaterialBronze
BrandDWYER INSTRUMENTS

Questions about this item

Will the 1/2" FNPT bronze body thread onto the existing 1/2" NPT steel pipe in my plant without an adapter?

Yes, the indicator has 1/2" FNPT connections that mate directly with standard 1/2" NPT male threads, so it threads onto your existing pipe without an adapter.

How do I confirm the rotor is spinning freely after I pressurise the line to 125 psig?

After pressurising, look through the two tempered-glass windows; the rotor should spin visibly with flow in any direction — horizontal left, horizontal right, vertical up or vertical down.

Does the package include the Buna-N seals or do I need to order them separately?

The Buna-N seals are factory-installed in the bronze body, so no separate seal kit is required for installation.

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