Water mist fire extinguishing system: a water distribution device that has water supply components or components that supply water and atomized media at the same time, and is equipped with one or more sprinklers that can spray water mist to control, suppress or extinguish fires.
Entire space fire extinguishing method: used to protect all hazards in the entire enclosed space.
Local application fire extinguishing method: a fire extinguishing system that sprays water mist directly to the protected object at a certain spray rate and lasts for a certain period of time.
Unit-independent system: A fire-extinguishing system that protects a protected area or protected object with one fire-extinguishing system.
Combined distribution system: a fire-extinguishing system that protects two or more protected areas or protected objects with a set of fire-extinguishing systems.
Water mist fire extinguishing mechanism
The water mist fire extinguishing system can protect the protected objects in various ways of extinguishing fire, suppressing fire, controlling fire, controlling temperature and reducing dust. Its fire extinguishing mechanism can be summarized as follows:
1. Efficient heat absorption
Due to the small diameter of the droplets of the fine water mist, the relative surface area is 1700 times larger than that of ordinary water droplets, and it can be completely evaporated in the fire field. According to 100 ℃, it can be seen that the heat absorption rate is high and the cooling effect is strong. 300kW, calculated, the heat absorption power of the water mist sprayed by each nozzle is about 2257kJ/kg, and the latent heat of evaporation of water is
2. Suffocation
After the fine water mist is sprayed into the fire field, it evaporates rapidly to form steam, and the volume expands rapidly, removing air and forming a barrier around the burning object to prevent the inhalation of fresh air. When the surrounding oxygen concentration drops to a certain level, the flame will be smothered and extinguished.
3. Block radiant heat
After the fine water mist is sprayed into the fire field, the vapor formed by evaporation quickly covers the combustion material, flame and smoke plume. Effect.
Control method of water mist fire extinguishing system
1. Automatic control: Select the control mode on the alarm fire extinguishing controller as “automatic”, so that the system is in an automatic control state. In general, the system is in this control mode.
2. Storage tank type: When a fire occurs in the protected area, the fire detector will send the fire signal to the alarm fire extinguishing controller, the alarm fire extinguishing controller will send out a sound and light alarm signal, and at the same time issue a linkage command, close the linkage equipment, and issue a fire extinguishing command to Control box; the control box first sends an instruction to open the solenoid valve, start the gas to open the bottle head valve of the pressurized driving device, release the driving gas (medium pressure: decompressed by the pressure reducer) into the fire extinguishing agent storage tank, and pressurize the storage tank. (Medium pressure: When the pressure of the storage tank rises to the upper limit (3.5MPa) set by the pressure gauge of the electrical node, the control box will issue another command) Open the selector valve of the corresponding protection zone, release the fire extinguishing agent, and implement the fire extinguishing. (Medium pressure: When the pressure in the storage tank drops to the lower limit set by the pressure gauge of the electrical node, the control box will issue an instruction to close the corresponding selector valve and stop releasing the fire extinguishing agent.)
When a fire occurs in the protected area, the fire detector will send the fire signal to the alarm fire extinguishing controller, and the alarm fire extinguishing controller will send out sound and light alarm signals, and at the same time, it will issue a linkage command, close the linkage equipment, and issue a fire extinguishing command to the control box; the control box first Send a signal to start the pump, open the solenoid valve of the pump and the selection valve of the corresponding protection zone. After the normal operation of the pump is ensured by the setting of the delay switch, the solenoid valve of the pump is closed. The protected area is sprayed with fine water mist to put out the fire. After extinguishing the fire, manually turn off the water pump to stop releasing water mist. The control box is powered off and the selector valve resets.
