The fire control valve and smoke exhaust fire damper have five test items: temperature sensor performance test; shutdown reliability test; salt spray test; air leakage test; fire test. The research of this subject is mainly for the latter two experiments.
(1) The concept of fire dampers and smoke venting valves
The fire damper is installed on the air supply and return air lines of the ventilation and air conditioning system. It is normally open. When the gas temperature in the pipeline reaches 70oC, it will automatically close, which can meet the requirements of fire resistance and fire integrity. , a valve that acts as a fire barrier.
The smoke exhaust fire damper is installed on the pipe of the smoke exhaust system and is normally opened. When the gas temperature in the pipe reaches 280 °C in the fire, it is automatically closed, and the fire resistance stability and fire integrity requirements can be met within a certain period of time. A valve that acts as a fire barrier.
(2) The role of fire dampers
A complicated air supply and exhaust system with complicated piping. In the air supply system, the wind sent by the blower must be distributed to each branch pipe through the main pipe; in the exhaust or smoke exhaust system, the wind or smoke is collected from the branch pipes to the main pipe and then discharged into the exhaust fan. Then, in the air supply system or the smoke exhaust system, if there is no blockage, the air supply volume and the amount of smoke exhausted cannot be controlled, and a large amount of air supply and smoke exhaustion are not required in the part where the air supply or the smoke is not required. The parts that need to be supplied with air or smoke are not supplied with air, smoked, or only a small amount of air and smoke. In order to cut off the piping that does not require air supply and exhaust, this requires a valve device.
In addition, the air volume of each part of the air supply and exhaust system is calculated through the pipeline, and the corresponding pipeline design is carried out. However, on the one hand, there is a certain deviation between the theoretical calculation and the actual situation. On the other hand, the operating conditions of the system are constantly changing. Therefore, the air volume of each part of the system must be adjusted accordingly, which requires a valve device.
Also, some ventilation equipment, such as centrifugal fans, are preferably started at no load during start-up because the motor has the lowest starting current and is safe for safety. This requires shutting down the system piping before starting. When the fan inlet and outlet have a switch, it is generally necessary to close the inlet or outlet. If the inlet and outlet do not have a switch, it must be controlled by a valve device.
(3) Setting of fire damper and smoke damper
A fire damper is arranged on the pipeline of the ventilation and air conditioning system, and a smoke venting fireproof valve is arranged on the pipeline of the smoke exhausting system to prevent high temperature toxic smoke transmission during the fire, which causes the fire spread and the toxicity is aggravated.
1. Fire dampers should be installed in the ducts of ventilation and air conditioning systems in one of the following cases:
(1) The pipeline passes through the partition wall of the fire partition;
(2) Pipes pass through ventilation, air-conditioning room and important or fire-resistant room partition walls and floor slabs;
(3) Horizontal pipe section at the intersection of the vertical duct and each horizontal duct
(4) The pipe passes through both sides of the deformation joint.
The fire damper in the above part is automatically closed when the temperature of the gas in the pipeline reaches 70oC.
2. Separation of the exhaust system: