CH10 Flashcards
(24 cards)
_______ serves as the difference in elevation between the surface of the static water supply and center of the pump intake.
Lift
pg 360
To begin drafting operations, most of the air inside the pump evacuates, creating a _______, which allow atmospheric pressure acting on the surface of the water of a static source to force the water into the pump.
pressure differential (partial vacuum)
pg 360
With the pump moving water, the vacuum reading on the gauge will indicate the remaining
capacity of the pump
pg 360
The maximum height of lift is affected by the length of the ____ (due to friction loss) the amount of ______ pressure (vacuum) that the priming device can produce, the existing _______ pressure, and the vertical distance from the water surface to the centerline of the pump.
intake hose, negative, atmospheric
pg 360
In the fire service, ________ means the greatest heigh to which any amount of water may be raised through an intake hose to the pump.
maximum lift (mathematical)
pg 361
Variables affecting maximum lift include the _______ pressure, condition of the fire _____, and _______, and the intake hose _____ and all valves.
atmospheric, pump, primer, and gaskets
pg 361
In most circumstances, maximum lift reaches about ____ feet.
25
pg 361
_________, which refers to the height of a column of water being lifted to provide a reliable fire flow.
Dependable lift
pg 362
After factoring in the surrounding atmospheric pressure and friction loss in the intake hose, every fully operational fire pump should have a dependable lift of at least __ feet.
15
pg 362
___ feet of water around a barrel-type strainer is generally considered the minimum for that equipment.
2
pg 366
Floating strainers may operate in water as shallow as ___ feet.
1
pg 366
Typically range from 10,000 to 100,000 gallons.
Cisterns
pg 369
______ typically receive water from a well or runoff.
Cisterns
pg 369
Large residential, industrial, or agricultural locations may feature ________. These may range in size from several hundreds to tens of thousands of gallons of water.
private water storage tanks
pg 369
________ serve as artificial installs that resemble ponds or lakes.
Ground reservoirs
pg 369
_______ may flow in excess of 1,000gpm and may function as a water source for fire protection.
Agricultural irrigation systems
pg 372
_______ generally supply water via open canals and portable pipes.
Irrigation systems
pg 372
In theory, ______ can be described as water being discharged faster than it comes into the pump. Sometimes referred to as “overpumping” or “overrunning the source”
cavitation
pg 373
During ______, the pressure drops so far below atmospheric pressure that water boils regardless of temperature at that point, the water changes to vapor and creates a void.
Cavitation
pg 373
______ velocity sits at the threshold point reached when volume decreases beyond the amount of water being taken in from a source.
Critical
pg 374
To avoid cavitation, keep discharge rates
lower than the intake
pg 374
Water below _____ or above ______ may harm the ability of the pump to reach capacity.
35 degrees Fahrenheit; 90 degrees Fahrenheit
pg 376
As the air evacuates from the pump, the master intake gauge will register vacuum reading. This should equal _____ for every ____ of lift required.
1 inch Hg; 1 foot
pg 377
A ________ may be used to employ a Venturi effect to achieve water movement during drafting operations.
jet siphon
pg 378
