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Tunnel Dampers
A tunnel transit damper is a heavy-duty flanged air damper designed to meet the rigorous environment of a transit tunnel. It is qualified to withstand the stresses and pressures of such environments. It meets the requirements of NFPA-130, NFPA-502, UL 555S, and BS476 standards.
OVERVIEW
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HTD-630
The HTD-630 is a heavy duty industrial air control damper qualified for use in tunnel and transit systems. This model has a double flanged frame and features mechanically fastened silicone blade seals and stainless steel jamb seals.
- Meets the requirements of NFPA-130, 502, and UL 555S
- Blade type: fabricated airfoil
- Pressure: Up to 24 in. wg
- Velocity: Up to 4,000 fpm
- Temperature: 250°F continuous; 482°F for 2 hours (NFPA-130, 502)
- Fatigue Cycles: 8 million reverse cycles at 24 in. wg
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HTD-636
The HTD-636 is a heavy duty industrial air control damper qualified for use in tunnel and transit systems. This model has a double flanged frame and features mechanically fastened silicone blade seals and stainless steel jamb seals.
- Meets the requirements of NFPA-130, 502, and UL 555S
- Fire Rating: BS476 two hours and approved for fire partitions of four hours or less where British Standards are required
- Blade type: Fire-rated fabricated airfoil
- Pressure: Up to 24 in. wg
- Velocity: Up to 4000 fpm
- Temperature: 482°F for 2 hours (NFPA-130, 502)
- Fatigue Cycles: 8 million reverse cycles at 24 in. wg