The working principle of fire door mainly includes two types of working mechanisms: normally open fire door and normally closed fire door.
Working principle of normally open fire door
The normally open fire door consists of a fire door, a door closer and a fire door release device. Under normal circumstances, the door leaf is kept open by the fire door release device. The control module or FMK controller of the fire control center outputs a DC24V working voltage to the electromagnetic door suction, so that the electromagnetic door suction hinge is positioned and the fire door is kept normally open. Once a fire occurs, the DC24V power is cut off, the electromagnetic door suction loses power and releases the door body, and the fire door is automatically closed under the action of the door closer. For double-open fire doors, the sequence is closed by controlling the delayed power-off sequence of the left and right doors, and the controller will feedback the release signal of the electromagnetic door suction.
Working principle of normally closed fire door
The normally closed fire door is always kept closed at ordinary times. When someone passes through, it is necessary to push the door leaf to open. After leaving, the door closer will automatically close the door leaf and restore it to its original state. This type of fire door is filled with highly fire-resistant materials, which can effectively block the spread of fire and smoke in the event of a fire. Once the steel fire door is manually opened by the escaping personnel, the door closer will immediately start, causing the door leaf to close automatically, thereby preventing the spread of thick smoke.
Definition and function of fire door
Fire door refers to a door that can meet the requirements of fire resistance stability, integrity and thermal insulation within a certain period of time. It is located between fire compartments, evacuation stairwells, vertical shafts and other locations, and has the function of preventing the spread of fire and smoke, ensuring the safety of personnel evacuation.