NKTM
Non-return damper, overpressure damper
NKTM - Non-Return Damper closes at reverse airflows in HVAC systems and shut off duct automatically. NKM - Non- return damper has function to prevent back air flow in the air duct and to be opened by air pressure in one direction. Its blade is loaded by weight on the site lever. The weight on the lever is adjustable.
Properties
•Dimensions from 200 × 200 to 1 400 × 1 400 mm
•Max. pressure difference 1 500 Pa, max. airspeed inside the duct 12 m/s
•Mechanical damper used for air backflow effect elimination
•Damper complete made of galvanized steel
•Rectangular damper from 150 × 150 to 600 × 350 mm
•Round damper from ø 125 to 315 mm (round NKM with flanges on both sites - up to max. 350mm)
•Round NKM has standardly rubber gasket sealing on both ends.
Specifications
Non-return dampers are used to close the duct automatically in case of fan being switched off. In case of a shutdown of one of the fans at fan parallel configuration, the dampers prevent reverse airflow.