NKTMJ
Non-Return/Back draft Damper resistant against seismic events
NKTMJ - Non-Return/Back draft Damper closes at reverse airflows in HVAC systems and shut off duct automatically.
Properties
•Min. dimensions 200 × 200 × 210; max. dimensions 2 000 × 2 000 × 210 mm (square cross-section only, round adapter available)
•Only mechanical variant
•Plain bearings, maintenance-free design
•Max. permissible leakage via closed blades - 2% of nominal airflow
•External casing leakage class C acc. to EN 1751
•Max. airflow 25 m/s
•Variant with, or without counterweight - adjustable system
•Mechanism installed externally of the damper axis and airflow direction
•Pressure difference up to 7 500 Pa (internal vs. external pressure)
•Carbon steel painted, galvanized, or stainless steel - casings made of 3 mm sheets, welded construction
•Radioactive aerosol impact allowed - decontaminable
•Seismic resistant (high resistance)
•Guaranteed service life 40 years, recommended maintenance interval 10 000 hours
Specifications
Non-Return/Back draft Damper closes at reverse airflows in HVAC systems and shut off duct automatically.