In the past, the kitchen fire extinguishing system was the fire extinguishing protection system of the pointer to the kitchen building itself, the most common smoke sense, temperature sense detection system and water sprinkler system. Because kitchen fires are mostly caused by the out-of-control of stove fire, igniting the grease scale in the hood of collecting oil and the smoke exhaust pipe causes the all-day fire which is difficult to extinguish. Therefore, the kitchen hot kitchen processing equipment "kitchen table, oil collecting hood, smoke exhaust pipe" has become the key protection object in the kitchen; and the system for kitchen hot kitchen processing equipment to achieve "local key fire protection" is called "kitchen equipment automatic fire extinguishing device", which is different from the kitchen fire extinguishing system, two independent and non-interference fire extinguishing protection systems.
Why set up kitchen equipment automatic fire extinguishing device with smoke extinguishing function?
Because kitchen fires are usually high flash point (315-450 degrees) cooking oil, their fire characteristics are: rapid expansion of fire, large heat capacity, strong smoke fire concealment difficulty to extinguish; therefore, rapid extinguishing of fire is one of the difficulties to extinguish kitchen fires, restraining re-ignition is the second difficulty to extinguish kitchen fires, curbing the spread of smoke fire is the third difficulty to extinguish kitchen fires.
Where is the automatic fire extinguishing device suitable for kitchen equipment?
The kitchen conditions suitable for public buildings such as hotels, restaurants, government offices, schools, enterprises and institutions meet the following standards:
(1) Kitchens in underground buildings; (2) Kitchens in supermarkets or adjacent kitchens with an area of more than 500 m2; (3) Kitchens with a restaurant area of more than 100 m2 in high-rise buildings; (4) Kitchens with a restaurant area of more than 200 m2 in single and multi-storey buildings.
Why should kitchen equipment automatic fire extinguishing devices use agents and water together to extinguish fire? What is the fire extinguishing mechanism?
Because kitchen is an important place for people's food processing, in order not to pollute food and avoid causing harm to human body, fire extinguishing agent should be non-toxic, non-polluting and non-corrosive special fire extinguishing agent; fire extinguishing agent should first extinguish the open fire of oil pan, smoke hood or flue, and then use water mist to absorb heat energy, prevent re-ignition, so as to achieve the purpose of rapid fire extinguishing. If only water can be used to extinguish the fire, but the extinguishing time will be much longer, and it will expand the burning range (hot oil will splash around when it meets water), and may cause personal injury.
How to define and divide the protected areas of automatic fire extinguishing devices for kitchen equipment?
The protection area of automatic fire extinguishing device for kitchen equipment refers to the protected area composed of a group of hot kitchen processing equipment, the corresponding length of the hood and the smoke exhaust inlet to the flue fire valve. A group of hot kitchen processing equipment can be protected by an automatic fire extinguishing device of kitchen equipment, and a set of inadequate equipment can be protected by vertical zoning of multiple automatic fire extinguishing devices of kitchen equipment.
The fire extinguishing principle of automatic fire extinguishing device for kitchen equipment is as follows:
(1) After the kitchen stove oil pan burns, the huge heat emitted by the flame makes the temperature-sensitive fusible metal cable releaser detached;
(2) The temperature sensing system opens the release device of the kitchen fire extinguishing system, pressurizes the fire extinguishing agent storage container, and simultaneously operates all auxiliary start-up or electric cut-off devices and alarm linkage devices;
(3) The liquid fire extinguishing agent sprays through the nozzle on the kitchen stove equipment surface and inside the exhaust hood, oil filter screen and smoke exhaust pipe. This special fire extinguishing agent can quickly extinguish the flame in the oil pan, and form a covering layer to inhibit the combustion of oil vapor to prevent oil reburning; (4) When the system agent is sprayed for about 3-5 seconds, the valve on the system automatically opens the spray valve, and water flows through the extinguishing. Powder pipes and nozzles are sprayed to quickly cool and wash the oil and the surface of stove equipment.