Hydraulic Calculations Flashcards
You have a 45m lay of 65mm hose flowing through a gated “Y” supplying two 44mm hose lays 60m long.
Each 44mm nozzle is flowing 720 litres/minute with a nozzle pressure of 350 kPa. What is the pump discharge pressure assuming no elevation change?
1290 kpa
You are supplying a Blitzfire with a fog nozzle flowing 1900 litres/minute through twin 65mm (Siamese) lines. What is the friction loss per 15m of hose?
36 kpa
You are supplying a Blitzfire with a 32mm nozzle flowing 1450 litres per minute. What is the friction loss per length (15meters) when using 60 meters of 65mm hose?
84 kpa
You need to supply two 44mm nozzles @ 700 litres/ minute each, 1 Blitzfire @ 1900 litres/minute and a 65mm hand line @ 1000 litres/minute. The hydrant has a static pressure of 550 kPa. What is the maximum forward lay from the hydrant to achieve the required fire flow?
7.0
Using the formula “PDP-TFL+APP+/- EP +P”, what does “EP” stand for?
Elevation Pressure
You are supplying a 44mm hand line flowing 700 lites/minute through four 15m lengths (60m) of 44mm hose. The fire attack crew is working 8 meters above the pump. What is the pump discharge pressure?
1018 kpa
What is the “EP” on a 20 story high-rise building (4.0m/floor) with a fire on the 13th floor?
480 kpa
You are supplying a Blitzfire with a 32mm nozzle flowing 1450 litres per minute. What is the total friction loss when using 60 meters of 65 mm hose?
336 kpa
Elevation Change
Add 40 kpa/floor above ground.
We count from the second floor because we are level with the first floor pumping.
If the fire is on the 4th floor, we calculate 3 x 40 kpa to give us 120 kpa.
At how many lengths of supply hose should the consideration of a relay be considered?
Relay should be considered at 3 lengths of supply line from the hydrant.
