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Flashcards in Pump Standards Deck (30):
1

Static pressure

Stored potential energy that acts equally in all directions in a fluid at rest.

2

Residual Pressure

Part of the total available pressure that is not used to overcome friction or gravity while water moves through pipes, fittings, fire hoses, and adapters.

3

Flow Pressure

The forward velocity pressure at a discharge opening while water is flowing (NP)

4

One gallon of water weighs?

8.33 lbs

5

One cubic foot of water weight?

62.5 lbs.

6

Gallons of water in a cubic foot?

7.5 gal.

7

cubic inches in one gallon?

231

8

Cubic inches in one cubic foot of water?

1728

9

Fire ground calculation of a circular tank?

6 x D2 x H

10

Water exerts a pressure of ______for every foot of depth?

.434 psi

11

Atmospheric pressure at sea level?

14.7 lbs.

12

As elevation increases, the atmospheric pressure decreases at approximately?

.5 psi for every 1000 feet.

13

Pump capacity?

100% rated capacity at 150 psi net pump psi
70% at 200
50% at 250

14

Net pump pressure?

a measure of the pressure that is produced by the pump. Difference between the pump discharge pressure and the incoming pressure.

15

Pumping 1 1/2 hose?

1 1/2 hose will be pumped at 100 psi plus 36 for every 100 feet at 100 GPM.

16

Max GPM through a 1 3/4" HR nozzle?

170

17

Max pressure pumped through a 21/2 or 3" supply line?

250

18

Max pressure to a 4" is 200 psi. 4" supply is?

185 psi max

19

How automatic nozzles work?

Designed to adjust the orifice size and thus the rate of flow to provide an effective stream using whatever flow is available at 100 psi. (HR at 75 psi.)

20

In replay pumping, maintain ___psi. intake pressure for the forward pumper.

10psi

21

Sprinkler GPM =

1/2 pressure + 15

22

Positive displacement pump?

High pressures at low volumes. Capable of pumping air, centrifugal pumps cannot. PDP's are used for priming pumps replacing air with water in the centrifugal pump.

23

Types of PDP's?

1. Piston pump
2. Rotary gear pump
3. Rotary vane pump (most common)

24

Centrifugal Pump defined.

A rapidly moving disk will throw water introduced at the center toward the outer edge. Advantage? It will use incoming pressure of the water.

25

Centrifugal pump facts?

Rotating wheel = impeller
water inlet = eye

26

Multi-stage pumps: series ?

series/pressure operation: The pump will be able to pump twice the pressure 1/2 the capacity.

27

Multi stage pump: Parallel?

Parallel/ Volume: will pump capacity of the pump but only 1/2 of the rated pressure.

28

Cavitation?

Air cavities are formed in the pump, resulting in vibrations loss of efficiency, and damage to the pump

29

Causes of cavitation?

1) Trying to pump more water than the hydrant can supply.
2) using too small of intake hose.

30

Waterous relief valve

if discharge valve is closed and pressure in the chamber exceeds the compression load of the spring, valve unseats. Water escapes to the pump suction through tube.