Heavy Duty Non Return Dampers

KHDR-NR Heavy Duty Non Return Dampers

• Please contact our Technical Sales Team for full Product Specification Details

  Casing:

  • 250 x 50 x 2mm thick mild steel, galvanised or stainless steel material. Folded and fully welded construction. Non standard flanges and 3mm thick casings available

  Blades:

  • 150mm pitch single skin 1.5 or 2.0mm thick material, overlapping action in mild steel, galvanised or stainless steel

  Shafts:

  • 20mm diameter continuous shafts in 316 stainless steel

  Linkages:

  • Side linkage, out of airstream, 3mm thick stainless steel quadrant arms and link bars.

  Bearings:

  • Oilite bushes (‐9 to + 70 deg. C) standard. High temperature Oilite bushes to 220 deg. C. Graphite bronze to 300 deg. C. 25% carbon filled PTFE (chemical resistance)

  Operation

  Gravity Operated:

  • Externally linked blades to move uniformly in response to air velocity and pressure

  Counterbalance Weights:

  • Counterbalance weights can be provided to:
  • Assist or restrict blade operation in response to airflow
  • Regulate blade operation when airflow is vertical
  • Weights are attached to an optional adjustable external crank arm.
  • *If required, the dampers can be pre‐set in our factory to open at a specific pressure

  Seals

  Blades:

  • Metal to metal overlapping blade operation. Blade ends – close fit to inner casing

  Shafts:

  • Oilite bush or glass filled PTFE bush as standard.
  • *Options available – Lip seals, "O" ring seals, flange mounted remote bearings. Enclosed and sealed linkages.

  Size Range:

  • From 200sq to 1250sq in one module. *Above these sizes in multiple modules with joint flanges

  Alternative Options:

  • Non standard casing depths and flange widths to suit customer requirements
  • Circular drilled flanges in RSA and to BS & DIN standard patterns
  • Polyester powder coat finish
  • Food quality options available, including gaskets