Friday, 31 October 2014

Abcs Of Fire Sprinkler Hydraulic Calculations

By Young Lindsay


Automatic sprinklers are a part fire extinguishing systems. Usually part of a fire protection system based on a water reservoir for the supply system and a network of pipes which are terminal elements. They usually are activated by detecting the effects of a fire since the temperature rise associated with fire, or smoke is generated by combustion (fire sprinkler hydraulic calculations).

A fire sprinkler is a device for extinguishing fires. Consists of an armature, with a pipe connected to a water pipe pressure. The pipe is closed with a cover subject by a glass capsule filled with a liquid whose boiling point is at a certain temperature (temperature trigger) which is subject against a disperser. When a fire occurs, the liquid boils and the steam breaks the capsule; the lid bounces, exits the water and crashes into the disperser sprinkling the burned area.

There are other automatic, instead of the capsule are connected to a fire detector which sends an automatic valve that opens when the detector knows of a fire. When quenched, the switch closes the valve and, if applicable, would open again if the fire is revived. Systems differ from sprinklers sprayed water on the element that disperses the water these last is a mouthpiece designed to offer an angle of fog.

The spray outlet is somewhat less sharp slope of the teeth to its plane and a little more in diameter; glass valve polished, chamfered and sprinklers have higher gate outlet. For some time, some of the sprinklers manufacturers to reduce the cost structure used as a sealant rubber gasket. Thus it was not taken into account that over time the elastic properties of rubber deteriorates, and can result in loss of containment. But the worst thing that can happen to the adhesion of rubber sealing surfaces.

Thermo-sensitive bulb. The most common sprinkler glass bulb holds the cap in place and containing therein a liquid that does not fill the bulb, leaving a gap. When heat from a fire acts on bulb, the liquid boils and vapor pressure breaks the glass stopper and then releases the pressurized water contained pipe network, download and poured over the baffle forming a jet sprayed water mist.

These processes may take more or less depending on rate of release of surrounding heat to spray, the distance between the sprinkler and ceiling, the distance between the spray and the floor, the roof slope and other factors that have been extensively studied by the NFPA (National Fire Protection Association), UL (Underwriters Laboratories), FM (Factory Mutual), among other research and development in flame protection systems.

Fire-extinguishing system is maintained in working order. Sprinklers should be regularly inspected for mechanical damage, corrosion, coating damage, obstructions irrigation. Damaged sprinklers must be replaced. Even small leaks require immediate replacement of the sprinkler. To do this, have an arsenal of spare sprinklers and constantly replenish it. Sprinkler who have been exposed to heat of combustion products exceeds the value of maximum allowable operating temperature must be replaced.

Another advantage of such a system is that the shot can be caused by smoke detection or detection of air ionization, since there are smoke detectors these extremes, while the temperature sensing function of temperature only. Its disadvantage is that, of course, is a more expensive installation.




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