pumps for private water systems Flashcards
how is a pump able to lift water from a well
by creating a partial vacuum in the pumping chamber
how does the diameter of a well affect pumping capacity
by limiting the size of pump you can install
what is the maximum theoretical lift of a centrifugal pump used as a suction pump
close to 34 feet
why is a jet pump capable of a greater suction lift than a centrifugal pump
jet pumps are better at developing negative pressure than centrifugal pumps
what is the difference between a shallow well and a deep well
depth to the pumping level of the well
how does the altitude of a pump installation affect pump selection and installation methods
higher elevations do not have as much atmospheric pressure
how does friction loss affect the use of a suction pump
by reducing the amount of work done by atmospheric pressure
what condition may cause cavitation for a centrifugal pump
pump is working at maximum lift capacity
what are centrifugal pump suction lines installed with positive grade from the well to the pump inlet
for better air elimination when priming
how may drawdown in a well affect an aquifer
drawdown can allow the aquifer to start releasing sand
why should pump capacity be matched to well capacity
to prevent aquifer problems from developing
when is a well considered to be a deep well
when the wells pumping level is deeper than 24 feet
why are some jet pumps called convertible jet pumps
the jet assembly can be removed from the pump and placed in a well
which piston pump can be offset from the top of a well
shallow well piston
which pumps may produce enough pressure to damage a pressure system
reciprocating and submersible pumps
what are helical screw pumps usually used for
pumping slurries and sludges
when a shut off valve is placed on a tank tee for a residential installation which side of the tank tee should i be placed on
outlet of tank tee
what is the pressure output of submersible pump impeller stage
9psi per stage
why does a submersible pump require a check valve at its outlet
to stop water from draining out of the drop pipe through the pump
what types of impellers are used on centrifugal pumps
closed, semi closed, open
what device is used on the outlet of two pipe jet pumps to allow the pump to produce the most water possible
a flow control fitting or valve
list the six components of a private water system
-electric motorized pumping unit
-pressure tank
-air volume control
-pressure switch
-relief valve
-foot valve
what is the correct ratio of water to air in a standard pressure tank
1/3 air and 2/3 water
a standard galvanized pressure tank that has lost its air charge is said to be
waterlogged
a standard galvanized pressure tank that contains 33.3% air and 66.6 % water will release 20% of its water before the pump must start again. this volume of water is called
usable water
an installation that requires air to be replenished in the pressure tank requires an air volume control. the two most common types of air volume control are
float type and diaphragm
the electrical device that turns the pump on and off is called a
pressure switch
a _______ is a type of vertical lift check valve on the suction end of the piping in the well
foot valve
define the term HEAD
a pressure expressed in terms of height of a water column in feet
define the term pressure
a measurement expressed in unit of weight per area, for example, pounds per square inch.
a pump works by creating a _______ on the inlet side of the pump, which allows atmospheric pressure to force water into the suction line
negative pressure
one pound of pressure will lift a column of water _____
2.31 feet
to convert feet of head to psi, multiply by ____
.433
list four types of pressure tanks
-standard galvanized tank
-floating disk
-diaphragm
-bladder
an air volume control is used on a bladder type pressure tank true of false
false
there is no contact between the water and the tank when the _______ type of pressure tank is used
bladder
what are the five steps for selecting and sizing of a private water system
-discharge pressure
-suction pressure
-pump capacity
-two pump system
-type of pump
list two things that will happen if the wire size to the pump is too small to adequately meet the power requirements
1 the expected life of the electric motor will be reduced
2 electrical energy will be lost in the form of heat in the feeder circuit
list two reasons why a well must be protected from surface water
1 surface water could contaminate a well
2 surface water could puddle and freeze, damaging pipe and other components
list four different types of wells
-drilled
-driven or jetted
-dug
-bored