The difference between normally closed fire doors and normally open fire doors

Introduction to normally open fire doors
①Fire doors set on evacuation passages
②Fire doors that lead from an independent fire protection zone to another fire zone in a building
③ Doors opened on the fire wall
④ In high-rise public buildings with densely populated areas, such as shopping malls, markets, hotels, restaurants, schools, teaching buildings, apartment buildings, etc. Fire elevators in these buildings are generally used together with passenger elevators, and the elevator front room is used with smoke prevention The stairwell shares the front room. The fire door at the connection between the shared front room and the evacuation passage should be a standard normally opened door. Because most of the indoor flow of people and logistics must enter the shared front room to take the elevator through the fire door, the disadvantage of setting up a normally closed fire door here is that a large number of people and logistics frequently use the fire door, which will have a negative impact on the fire door itself and the sequencer. The door closer was seriously damaged, causing the user unit to frequently replace the door closer sequencer. Some units even used other measures to fix the normally closed fire door to the wall in order to facilitate personnel entry and exit. When a fire breaks out, everyone in the room rushes to escape. At this time, the fire door also loses its normal closing function, so that smoke will enter the shared front room, the escape stairwell is no longer safe, and firefighters cannot escape. Fire elevator goes into the front room to rescue people and put out the fire.
Introduction to normally closed fire doors
In order to prevent smoke or fire from entering the evacuation passage stairwell through the door opening during a fire, and to ensure the relative safety of the evacuation passage and the safe evacuation of personnel, these parts The fire door should be kept closed at ordinary times and can close itself after the evacuation of people in case of fire. Normally closed fire doors should be installed in the following places and locations: high-rise residential buildings, pipe wells, fire control rooms, fire pump rooms and other equipment rooms attached to the building. The daily flow of people and logistics in these buildings and locations is relatively fixed. In actual use, the closed function of normally closed fire doors can be guaranteed.
Control methods of normally closed fire doors and normally open fire doors.
Normally closed fire doors are generally composed of fire door frames, door closers, seals, etc. Double or multi-leaf normally closed fire doors are also equipped with sequencers. Normally closed fire doors do not need to be equipped with electric automatic control. Mainly used door closer sequencer for closing. Normally open fire doors are generally composed of door frame, door closer, sealing strip release switch and other components. Its automatic control principle is that normally open fire doors are controlled by the fire door release switch. The switch is usually installed on the wall or on a homemade bracket. At the right height from the ground, the fire control center control module or controller usually outputs working voltage to the electromagnetic door suction to keep the fire door in a normally open state. In the event of a fire, the smoke or heat detector transmits the detected signal to the control switch, and the power is cut off, causing the electromagnetic door suction to lose power and then release the door body. The fire door is closed by the door closer, and the double-leaf fire door is controlled by the left and right doors. Delayed power-off sequence shutdown, and feedback shutdown signal at the same time. Normally open fire doors must be reset by on-site manpower. After reset, the fire door status signal will be fed back to the fire control room.
If you have any questions about fire doors, we will try our best to answer them for you. For more details, please visit the official website of Shenzhen Tongxiao Industrial Co., Ltd. or consult the relevant staff