Flex Flange

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Flex Flange

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Flex Flange
Flex Flange Front
Flex Flange Side

  • Summary
  • Applications

    Flex Flanges are used in pairs to connect circulating pumps in hydronic systems. Armstrong Flex Flanges rapidly isolate a circulator for service, and eliminate the need to drain and refill the entire system.

  • Description

    Armstrong Flex Flange is a rotating flange designed to allow maximum installation flexibility regardless of pump flange orientation. Flex Flange units are available with a spring check valve to prevent the heating medium flowing in the wrong direction in the event of gravity circulation.

    The Flex Flange integrates a 2-bolt flange connection (common to small circulating pumps) with a full-port ball valve. This practical "all-in-one" design reduces the number of plumbing connections and results in a more reliable and easily-serviced hydronic system.

  • Materials

    Valve and Stem: Brass
    Flange: Cast Iron/Chromate
    Ball: Chrome plated brass
    Stem O-Rings: Buna N
    Seat: PTFE

  • Performance range

    Max working pressure: 150 psig (10.3 bar)

  • Temperature

    Max operating temp: 250°F (121°C)

  • Size

    0.5 - 1.5 inches

Lowest Life Cost

  • Dielectric sleeve prevents galvanic corrosion
  • NPT and sweat connections
  • 1/4 turn open/close lever-style handle
  • Dual Buna N O-ring seals prevent stem leaks
  • Corrosion-resistant brass body and flange

Easy to install

  • Slotted flange bolt holes
  • Rotating flange is faster and easier to install
  • Includes mounting nuts and bolts

Learn more


Flex Flanges

Hydronic Specialties

Installation & Operating Instructions


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