【 Weak current College 】 dry powder fire extinguishing equipment application and selection

Powder extinguishing agent is dry and easy flow of fine powder, consisting of a fire and a small amount of inorganic additives by drying, crushing, a mixture composed of fine powder. It is now in the fire has been widely used by a fire extinguishing agent. In addition to fight metal chemical fire extinguishing agent of dedicated dry powder, powder extinguishing agent will generally be divided into BC powder and ABC powder two categories; now the domestic fire enterprise and developed a kind of fine powder extinguishing agent, due to the small size, you can kind of gas release from space, in the core technology, some fire enterprise developed ultra-fine powder series automatic fire extinguishing products, so that the application of dry powder fire extinguishing products and technologies content is widening and upgrading, becoming instead a "Haroun" product direction.

Extinguishing gas under pressure, mainly through the action of powder spray and flame exposure, mixing occurs when the physical and chemical effects of fire. In addition, there are parts of the dilution effect of oxygen and cooling.

Automatic fire extinguishing system (fire fighting) is determined by the cylinder, pressure gauge, nozzles, etc, with the pressure moves the filling out of the fire-extinguishing equipment. Dry powder fire extinguishing equipment and many types of fire extinguishers, fire extinguishing appliances use a wide range of subjects, the author's fire protection engineering company used a variety of dry powder fire extinguishing device, in the design of automatic fire engineering gained some experience, in this case-by-case basis on how to choose a dry powder fire extinguishing equipment for a presentation, for peer reference.

Second, fire classification

Find out how equipped with dry powder fire extinguishing device, the first thing to understand is a basic tenet of fire classification. Classification according to national standard fire fire of fire into A, B, C, D, E 5, mean respectively:

A class of fire: the fire of solid substances. This kind of material often have a general nature, organic substances in combustion produces burning embers. Such as wood, cotton and hemp, paper, and so on fire.

Class b fire fire: means the liquid and solid substances can be molten fire. Such as petrol, kerosene, oil, methanol, ethanol, asphalt and other fire.

Class c fire fire: gas. Such as natural gas, hydrogen, methane, gas, etc.

Class d fires: metal fire. Such as potassium, sodium, titanium, lithium, aluminum-magnesium alloy fire.

E class fire: live fire equipment. Such as generators, cable, home appliances, etc.

Third, the extinguishing agent classification

Powder extinguishing agent will generally be divided into BC powder and ABC

Dry powder, off class d fires BCD powder now rare production; market emerging new products: ultra fine powder extinguishing agent whose performance should also be incorporated into the ABC's big class, although the efficiency of ultrafine powder fire extinguishing is greater than normal ABC powder, but its fire category and is the same as ordinary ABC powder extinguishing agent, can wipe out ABC class fires and electrical equipment fire; in order to understand its performance, we introduce separately.

1, BC powder extinguishing agent: BC class dry powder fire can be extinguished BC class. Applies to flammable and combustible liquids, gas and electrical equipment in the early stages of the fire, not suitable for solid substances fire. Therefore, in distribution room, kitchen, room, prone to combustible liquid gas fire and live fire places, equipped with BC powder extinguishing agent. But these sites are often not purely liquid and gas fire; therefore, this class places are mostly equipped with ABC class powder extinguishing agent.

2. ABC powder extinguishing agent: this type of extinguishing agent to fight the solid, liquid, gas and electric equipment fire, the most widely applicable.

Can be used for all kinds of public, Office, hotel, hotels, cars, ships and even family, but may not be used for fire extinguishing metal materials. There are now many should be equipped with ABC powder extinguishing agent's premises are incorrectly with BC powder; for example, some hotels are equipped with a fire extinguisher are all of BC powder, but from the fire of the comprehensive study, the hotel fire are combustible solids combustion, at this moment if you use BC powder extinguisher, the effect would not be significant and may even delay fire extinguishing time, resulting in greater economic losses.
3, ultra-fine powder extinguishing agent: at present, there are two types of ultra-fine powder products, of which one is the normal ABC powder filtered, thin section called ultrafine powder, average particle size of 10 microns to 20 microns; its fire extinguishing efficiency than conventional ABC powder is more efficient to 1-2 times; other properties are the same as with ABC powder. Another way is by Wuhan green fire developed "Superfine powder extinguishing agent"; this is a non-toxic, harmless to human skin irritant, on protection from non-corrosive; in normal not to disassemble, not caking moisture, not with good fluidity, diffuse and electric insulation of new fire extinguishing agent, with an average particle size of less than 5 microns, fire extinguishing efficiency is ordinary powder of 6-10 times.

4, ultra-fine powder and ordinary ABC powder extinguishing agent: ordinary ABC powder (including ABC ultra-fine powder) using silicone coated Technics moisture-proof, diameter 40 microns whole drowning fire effects; easy caking, moisture protection of corrosive, silicone oil is melting so dry adsorption in protection, it is difficult to clean, dry damp when the electrical conductivity. Wuhan green fire developed "Superfine powder extinguishing agent" is a natural moisture, no silicone coated, high insulation powder. Because the size is smaller than 5 microns whole drowning fire extinguishing performance is very good, has created a domestic fire extinguishing agent of three of the most (as far as the novelty search report: fighting the most efficient and fastest fire, fire extinguishing concentration minimum), due to non-toxic, harmless to human skin irritant, on protection from non-corrosive; can be applied to electronic equipment, precision instruments and fire-fighting; is the alternative "halon fire extinguishing agent's best products".

IV comparison of dry powder fire extinguishing device

Dry powder fire extinguishing equipment and many types of fire extinguishers, ABC dry General to portable and trolley, etc mobile fire extinguishers, the market also has an ABC powder fixed temperature suspended the automatic fire fighting equipment, fire-because of itsEfficiency is too low, can only be applied to local fire protection, few are chosen. Use of dry powder fire extinguishing device only ultra-fine powder series.

1. pulse of ultra-fine powder automatic fire suppression equipment, supersonic ultra-fine powder automatic fire-extinguishing appliances (filling the ABC fine dry powder): these two types of automatic fire-extinguishing device in main features rely on gas-driven, when protecting regional fire, the fire lit the fuse (or known as thermal line), installation of propellant powder instant explosion, produce a large volume of gas introduced powder extinguishing agent fire suppression; its application is successfully resolved the problem of ABC powder agglomeration, and ability to achieve rapid fire extinguishing purposes. However there are obvious defects: a is not fundamentally resolve ABC powder on protection from corrosion, difficult to clear, all submerged bad effect, moisture, after conducting an inherent defect; the second is the tremendous explosion of gunpowder sound and shock wave on protection from injury, some places have a linkage, the great shock and fire most likely secondary disasters.

2, ultra-fine powder extinguishing devices: this type of fire fighting installations nitrogen as dynamic, driven fire-fighting equipment in the ultrafine powder extinguishing agent for fire fighting; a quiet boot, nitrogen pressure 1.2MPA, safe and reliable, on the protection of any damage, except for fire extinguishing agent green features, the most efficient of its fire fighting, fire fighting fastest, fire extinguishing concentration minimum characteristics of fully complies with today's most demanding fire, it is important that this fire suppression equipment technology content is high, hanging, Cabinet, wall-mounted, network-can interfaces with fire alarm system, automatic fire extinguishing system comprising; its no pipe fire suppression system (hanging, Cabinet, wall-mounted) and ease of installation, low cost; network and no network can put out the fire of a larger space, the whole or partially submerged in the fire protection of fire-fighting applications flexibly select; there are three startup mode: fixed temperature-controlled start, start, superconducting start, according to the scene environment flexibility, a wide range of applications, especially suitable for steel, power generation, chemical, oil and other enterprises of cable tunnels, mezzanine, hydraulic station, oil, oil tank, etc in various types of fire.

5. concluding remarks

Select Automatic dry-powder fire extinguishing device class, one must consider the fire performances, modern fire requirements are early suppression, rapid response, efficient extinguishing; second, it is necessary to consider the relevance of the selected medium to suitable for protected material characteristics and requirements, if you choose ABC powder to protect the computer room, it was absolutely wrong; the third is to consider its security, for example in flammable and explosive place and underground works in the explosive start of fire suppression equipment, can only be increased fire loss; fourth, it is necessary to consider the economics, fire extinguishing concentration low dosage, late is low maintenance and replacement costs less to expire (i.e.: disposable and can be repeated filling of comparison), installation is simple and reliable.