Fire Damper
Fire dampers are installed in an air-distribution system, and are designed to close automatically upon detection of heat, to interrupt migratory air flow, and to restrict the passage of flame. They are required in order to maintain the required integrity of a fire resistance assembly when ducts penetrate fire-rated walls, partitions, or floors.
Fire dampers are required by either the model building or mechanical codes or National Fire Protection Association
(NFPA) 90A,Standard for the Installation of Air Conditioning and Ventilating Systems
STATIC FIRE DAMPER
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- A fire damper that is listed and approved for use in duct systems where the HVAC system blower will be cycled off during an alarm ( fan off ) , probably turned off by means of an automatic fire detector.Also referred to as a standard fire damper.
DYNAMIC FIRE DAMPER
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- A fire damper that is listed and approved for applications where the HVAC system blower may continue to run during an alarm. Dynamic fire dampers are rated to close against moving air measured in feet-per-minute (fpm )velocity.
DUCT MOUNTED TYPE
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- A fire damper with blade and frames out of air stream It is approved for use in walls , floors and partitions with fire rating of 1.5 hour.
SLEEVE TYPE
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- it is used when the air flow interruption from the stuck of blades in the fire damper frame is not a prime concern or consideration . it is easiest and fastest type to install .shelve Of various lengths and gauges to insure field compliance with UL installation requirement
FRAME
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- Formed from GADGE 16 (1.5) galvanized steel sheet
BLADES
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- The blades are roll formed interlocking blades manufactured from 0.8 mm galvanized steel.The blades are connected together to work as curtain.
FUSIBLE LINK
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- Standard release 74°C. (165°F) UL listed.Other temperatures available on request.Fusible links are held across the retracted damper blade pack, preventing it from closing at normal temperatures.
MICRO-SWITCH
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- The micro-switch is a single pole, double throw switch with a set of normally open contacts and a set of normally closed contacts.The micro-switch will trip when the fire damper curtain closes When the switch is tripped, the contacts that close can complete an alarm circuit to a control station that alerts the operator of which fire damper is closed. Also, the contacts that open can shut down the HVAC system blower motor
CLOSURE SPRING
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- Different stainless steel springs are used to positively close the fire damper curtain when the fusible link opens. Springs are required for all fire dampers used in horizontal applications and all dynamic fire dampers.They are installed on both sides of the fire damper.
LOCKING RAMP
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- On a fire damper, the locking ramp catches and locks the leading blade of the curtain when it closes..
FIRE RATING
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- Fire dampers with a 1.5 hour rating can be installed in fire barriers .