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1

Friction loss in 2 1/2" hose, field hydraulics

Flow (GPM) minus 100, drop the last digit, gives FL per 100 ft
Example: 210-100 = 110, drop last 0 = 11 psi per 100
Applicable for 150 to 350 GPM

2

Friction loss in 4" hose, field hydraulics

Flow x2 -4 = FL per 100 ft up to 800 GPM

300 GPM = 2 psi
400 GPM = 4 psi
500 GPM = 6 psi
600 GPM = 8 psi
700 GPM = 10 psi
800 GPM = 12 psi

3

How many gallons of water are in a cubic foot of water?

7.48 gallons

4

Nozzle range rule of thumb

1 psi of NP = 1 foot of range

5

How much water is in 100' of 1 3/4" hose?

12.5 gallons

6

How much water is in 100' of 2 1/2" hose?

26 gallons

7

How much water is in 100' of 4" hose?

65 gallons

8

How much water is in 100' of 5" hose

102 gallons

9

How much does 1 gallon of water weigh?

8.34 pounds

10

What makes a diesel engine fire?

Heat of compression, not from spark of a spark plug

11

What types of brakes are used on all engines?

Front are disc brakes. Rear are drum brakes. Parking brake is spring brake.

12

Minimum air pressure to move apparatus?

60 psi

13

Spring brakes are automatically applied at what pressure?

40 psi

14

Normal operating pressure of brakes

90-120 psi

15

What pressure does the compressor kick in?

100 psi

16

What is brake fade?

When the brake drums become too hot and expand away from the brake shoes.

17

What does shoreline power do?

Provides conditioning of all batteries, power to the block heater, and on board chargers such as TIC, e-tool batteries, flashlights

18

Rule for volume vs. pressure mode

If you are going to flow more than half of the rated capacity of the pump, pump in volume.

19

Rule for switching between volume and pressure

Must be less than 50 psi difference between intake and discharge, or switch at idle

20

Static Pressure

Pressure of fluid at rest. You connect to a hydrant and open the hydrant but no water is flowing. The intake gauge will read static pressure.

21

Residual Pressure

Pressure remaining after water is flowing. Connect to a hydrant, open a discharge, and the intake gauge will drop from its static reading, showing residual pressure.

22

Head pressure Equation

Head pressure in psi = Height in feet/2.304

23

2 settings on the Blitzfire Fog Nozzle

Low Pressure = 55 psi. Standard = 100 psi

24

Distance between fire hydrants

700' in residential, 400' in commercial, 300' in industrial

25

The most common type of positive displacement pump used in priming pumps are

Rotary vane