Type : Tunnel Ventilation Fire / Smoke Damper
Fire Rating : 4 hours as per BS 476
Blade : Aerofoil Type
Construction : Galvanized Steel (GI) | Stainless Steel (SS)
BETEC CAD’s Ventilation Dampers are designed to isolate sections of a ventilation system with very high level of sealing. The dampers are mounted in side of the tunnel or at tunnel ends to control the pressurized air, air intake and smoke exhaust in long tunnels without intermediate supplies.
In emergency situations , for fire and smoke control, the dampers pressurize the tunnel for safe egress of train, automobile, passengers to escape and creates a negative pressure in the area of the fire to remove smoke and gases.
BETEC CAD’s Tunnel Ventilation Dampers are heavy duty and robust dampers requiring less maintenance and are suitable for high humidity, high pressure, dust laden environments making them ideal for installation and operation in Tunnels, Oil & Gas, Marine and Nuclear applications.
Data
Damper Ratings
Fire Rating : 4 hrs vertical / 3 hrs horizontal as per BS 476
Leakage Rating : Class I @ 350° F as per UL 555S
Operational Rating : 250° C for 2 hours. (as per HKFSD)
Air Velocity : 4000 fpm (20 m/sec)
Pressure : 8″ water gauge (2KPa).
Max . Holding Pressure : 20” W.g (5Kpa)
Fatigue cycles : 3.5 million simulated transient pressure reversals (under process)
Standard Construction
Frame
14 gauge (2 mm) thick stainless steel sheet with 2″ (50mm) external flanges.
Blades
Aerofoil blades of 14 gauge (2 mm) thick roll formed stainless steel.
Blade Seals
300°C high temp, resistant Silicon rubber blade seals.
Jamb Seals
Stainless steel.
Bearings
High temperature resistant concealed ball bearings.
Axle
¾” (19 mm) diameter.
Actuator
Pneumatic.
Optional Fittings
Limit Switches
For Open / Close Indication.
Pressure drop for Dampers
- Pressure drop and resistance of multi- leaf damper is a function of airspeed and varies in relation to the system’s total pressure.
- The pressure drop is indicated in graph for opposed blade damper in 100 % open position.
- The pressure drop indicated is the difference in measured pressure before and after the damper.
