Several common extinguishant and fire extinguishers
|
| Updated：2011.02.13 Source：Zhejiang Fujie Fire fighting Equipment Co.,Ltd. Clicks： |
| |
1. The water is nature's most widely distributed, the most cheap extinguisher, because water with high heat (4.186 J/g ℃) and dives turn heat (2260J/g), so in extinguishing the cooling effect obviously, its fire-extinguishing mechanism relies mainly on the cooling and choking function to extinguish fire. The major disadvantage of water extinguisher is produced W.P.A loss and cause pollution, cannot be used in charged of fire fighting.
2. Foam extinguisher: through water immiscible, adopting mechanical or chemical reaction method produce a foam fire extinguishing agent. Generally by chemicals, hydrolyzed protein or by surfactant and other additives solution composition. There are usually chemical foam extinguisher, mechanical wan foamed extinguisher, detergent foam extinguishing agent. Foam extinguisher extinguishing mechanism mainly is cooling, asphyxia function, or in the burning of the air on the surface of the formation of a continuous foam layer, through the foam itself and the precipitation of the mixture of air cooling surface, and through foam layer covering action to make the air with oxygen to isolate and extinguish fire. The major disadvantage foam extinguisher W.P.A loss and pollution, cannot be used in charged of fire fighting.
At present, in fire system is mainly used in the air bubble mechanical wan foamed. According to the foam multiple can be divided into three kinds: foam multiple in 20 times the following called lower multiples foam, In the 21-200 times between the called multiples foam, In 201-1000 times between called high multiples bubble.
3. Dry powder extinguisher: it is used for fire extinguishing the dry, flows easily subtle powder, by a fire extinguishing efficiency of salts and a small amount of additive by drying, crushing, fine solid powder mixture composition. Mainly chemical inhibition and choking role to extinguish fire. Except special saves metal fire outside, dry powder extinguisher commonly used dry powder extinguisher typically divided into BC dry powder extinguisher and ABC dry powder extinguisher two categories, such as sodium bicarbonate sodium salt powder dry, modification, ammonium dihydrogen phosphate powder, ammonium phosphate powder, phosphoric acid hydrogen two powder etc.
Dry powder extinguisher mainly through the pressurized gas under the action of ejective mist and flame contacts, powder mixed occurs when the physical, chemical function to extinguish fire. One is by powder of inorganic salt volatile decomposition products and combustion process combustion substances produced by free radicals or active base produce chemical inhibition and negative chemical catalytic effect, make the burning chain reaction to interrupt and extinguishing, 2 it is by dry powder fell to burnable on the surface, produces chemical reaction, and in high temperature effect formed under one layer on layer, thus isolation oxygen suffocation extinguish fire. Dry powder extinguisher the major disadvantage for precision instrument fire easily cause pollution.
4. Carbon dioxide is a gas extinguisher, exist in nature also are broad, price low, get easy, its fire-extinguishing relies mainly on the suffocation function and partial cooling. The major disadvantage is fire-extinguishing need high concentration, can make the person were choking poisoned.
5. The fire extinguisher halogenated silane alkoxy mechanism is halogenated contacts high temperature surface or flame, decompose the activity of free radicals, produced by bromine and fluorine etc halogen hydride negative chemical catalysis and chemical purification, large flapping catch, consume combustion chain reaction generated in free radicals, damage and inhibit the burning chain reaction, and rapidly take the flame; By chemical inhibition to extinguish fire. In addition, still partial dilution oxygen and cooling effect. Halogenated silane extinguisher major disadvantage is the ozone layer. Now commonly used halogenated silane extinguisher has 1211 and 1301 two kinds. 1211 extinguisher formula for CF2ClBr, is the present domestic usage largest kind of halogenated silane extinguishing agent. 1211 extinguisher is a low boiling point of liquified gases, with effective extinguishing low toxicity and corrosive small, long store deteriorate and fire after a trace and no pollution protected objects, electrical insulating performance and good, but its chemical stability of the atmosphere is good, ozone destroy seriously, therefore the international advanced country has begun to work out. In our country after 2010 will also give fall into disuse. 1301 extinguisher toxicity, low in halogenated silane fire-extinguishing agent toxicity is lower one, so it can use, but someone under the condition of the stability of 1211 extinguisher than 1100 better, to the atmosphere the destruction of the ozone layer and hence greater to be replaced product. |
Traceability queries
新聞中心 
Current position: Home - News
> Fire knowledge