Fire pump important knowledge
The temporary high pressure fire fighting water supply system, stabilizing high pressure fire water supply system must be set fire pump.In the series in fire water supply system, fire water system and gravity in addition to need to set up the fire pump, still need to set the fire pumps.Fire hydrant water supply system and automatic sprinkler system should be set fire pump, respectively.
Fire pump should be set standby pump, its performance should be consistent with the working pump performance, but the following construction can not set the standby pump:
1, building height less than 54 m homes and outdoor fire water supply design flow rate is less than or equal to 25 l/s architecture.
2, indoor fire water supply design flow rate of less than or equal to 10 m/s architecture.
2.The fire pump series and parallel
Fire pump series is a of the outlet of the pump and a pump suction pipe connected directly and two pump running at the same time, fire pump in series at constant flow can increase lift.
Fire pump in parallel by two or more stations and two fire pump water to the fire water system at the same time, the flow of parallel main is to increase fire pump.
3.Fire pump and fire pump line setup requirements
1, fire pump should be taken from the water filling type.
2, fire pump pumping water directly from municipal pipe network, should be set on fire pump outlet pipe with air partition of backflow.
3, when water inlet place without water Wells, water inlet cyclone should be set up preventive device.
4, a group of fire pump, the suction pipe should not be less than two, when one of the damaged or maintenance, all the rest of the suction pipe should be still can pass the fire water supply design flow.
5, fire pump suction pipe layout should avoid formation of airbags.
6, a group of the fire pump should be not less than two water mains and fire water loop pipe network connection, when one of the water pipe repair, the rest of the delivery hose should be still able to supply all the fire water supply design flow.
7, fire pump, water inlet of submerged depth should meet the requirements for safe operation of the fire pump in the lowest level, suction pipe bell mouth under fire pool minimum effective water submerged depth of flow velocity in city should be based on the suction pipe and hydraulic conditions, but should not be less than 600 mm.When using vortex preventive device, submerged depth should not be less than 200 mm.
8, fire pump should be set on the suction pipe of rising stem gate valve or butterfly valve with self-locking device, but when setting non-rising stem valves shall be equipped with open scale and signs;When the pipe diameter more than 12, appropriate set of electric valve.