Structure and operation
A sprinkler system consists of:
- pump station with a water tank;
- distributing pressure pipelines;
- sprinkler substation with control-alarm valves;
- grid of sprinklers.
There are three main types of sprinkler systems:
- WET SPRINKLER SYSTEM for standard applications
In a wet sprinkler system, the distributing pipeline is constantly filled with pressurized water. The sprinklers are closed in glass bulbs with a thermally expanding liquid. The bulbs break when the temperature rises as a result of fire, starting the fire extinguishing process. The sprinklers release water which hits the deflector and sprays evenly above the fire.
- DRY SPRINKLER SYSTEM dedicated to facilities where the temperature constantly or periodically drops below 4°C.
In a dry sprinkler system, the distributing pipeline is filled with compressed air or nitrogen. When the temperature rises, the bulbs break and the sprinklers open. The air pressure drop causes the control-alarm valve to open, filling the pipeline with water which is released through the open sprinklers.
- DRY PRE-ACTION SPRINKLER SYSTEM for facilities particularly sensitive to water
In order to minimize the risk of sudden water outflow, the distributing pipelines in this sprinkler system type are filled with compressed air, and the fire extinguishing process is activated in two stages: by an external fire detection system and by heat-sensitive glass bulbs in the sprinklers. This minimizes the risk of a sudden water outflow, e.g. as a result of an accidental sprinkler damage.
In each sprinkler system, the water is released only by the sprinklers in which the heat-sensitive glass bulbs has broken. Consequently, the firefighting operation takes place only in the areas where the temperature has risen above the set threshold. This minimizes the water consumption, and the system can be quickly restored to the state of readiness.