Power Engineering - 4B2 Practice Questions and Answers Rated A
A pump is capable of suction lift due to
a. its ability to convert kinetic energy into potential energy
b. the speed at which it operates e. atmospheric pressure
c. its input power
d. its size
e. atmospheric pressure
Centrifugal pumps do not develop good suction lift be-
cause
a. atmospheric pressure is usually too low
c. their internal component clearances are too high
b. the pumped medium relative density is too high
c. their internal component clearances are too high
d. the speed is too low
e. they favour pressure rather than volume
It is generally accurate to say that
a. 9.8 kPa pressure results from every metre of water
depth or height
a. 9.8 kPa pressure results from every metre of water depth
b. a water height or depth of 10.34 metres results in 1 kPa
or height
c. 1 kPa will result from a water head of 9.8 metres
d. 10.21 kPa will result from 1 metre of static water head
e. atmospheric pressure has no bearing on static water
head
Preferably, dynamic pumps should be located
a. directly under the liquid source when suction lift is
e. below the liquid source when suction head is involved
involved
b. above the liquid source when suction head is involved
c. above the liquid source when suction lift is involved
,d. at the liquid source level when suction lift is involved
e. below the liquid source when suction head is involved
The vertical distance from the liquid surface up to the
pump centre-line plus the vertical distance from the pump
centre-line up to the surface of the liquid in the discharge
tank is
e. total static head
a. static discharge head
b. static suction head
c. suction lift
d. total discharge head
e. total static head
The ditterence between static suction head and static dis-
charge head is
a. total static head
a. total static head
b. static discharge head
c. static suction head
d. equivalent head
e. dynamic head
When a pump discharges into a vessel operating at 300
kPa, the 300 kPa is referred to as
a. dynamic head
b. equivalent head
b. equivalent head
c. discharge head
d. friction head
e. total static head
The total static head of a pump
a. is the capacity of the pump
,b. is the ditterence between the static suction head and
the static discharge head
b. is the ditterence between the static suction head and
c. is the discharge pressure in metres
the static discharge head
d. is all the parts of the pump casing
e. is the discharge head of the pump
When a reciprocating pump discharges while its piston or
plunger moves in only one direction, it is termed a
a. positive displacement unit
b. single acting unit
b. single acting unit
c. dynamic unit
d. double acting unit
e. duplex unit
Centrifugal pumps convert rotating mechanical energy
into kinetic energy then
a. discharge the kinetic energy
d. into potential energy in the form of pressure
b. back to mechanical energy
c. absorb the energy
d. into potential energy in the form of pressure
e. into centrifugal force
A hot water heating system circulator should
a. be directly coupled
b. have its own vibration-free base c. be very quiet in operation
c. be very quiet in operation
d. develop an extremely high ditterential pressure
e. not run continuously
The capacity of a centrifugal pump
a. varies with discharge pressure
, b. can be altered by speed variation only
c. indicates that the unit is a positive displacement type
d. should be varied by suction valve manipulation a. varies with discharge pressure
e. is fixed and can only be altered by changing the im-
peller
Centrifugal pump power requirements are decreased
when
a. discharge pressure is decreased
b. the litres moved per minute is decreased
b. the litres moved per minute is decreased
c. the casing pressure drops
d. the discharge velocity is high
e. the discharge head is at minimum
A rotary pump
a. is a variety of dynamic unit
b. never has discharge pulsations c. should be equipped with a relief valve
c. should be equipped with a relief valve
d. has the highest capacity of any pump
e. never requires cylinder lubrication
When starting-up a rotary pump you must be sure that
the
a. discharge valve is closed
b. discharge valve is open
b. discharge valve is open
c. pump is filled with air
d. pump is at the correct temperature
e. pump suction valve is closed
Rotary pumps:
1. are high pressure pumps
2. must be primed
A pump is capable of suction lift due to
a. its ability to convert kinetic energy into potential energy
b. the speed at which it operates e. atmospheric pressure
c. its input power
d. its size
e. atmospheric pressure
Centrifugal pumps do not develop good suction lift be-
cause
a. atmospheric pressure is usually too low
c. their internal component clearances are too high
b. the pumped medium relative density is too high
c. their internal component clearances are too high
d. the speed is too low
e. they favour pressure rather than volume
It is generally accurate to say that
a. 9.8 kPa pressure results from every metre of water
depth or height
a. 9.8 kPa pressure results from every metre of water depth
b. a water height or depth of 10.34 metres results in 1 kPa
or height
c. 1 kPa will result from a water head of 9.8 metres
d. 10.21 kPa will result from 1 metre of static water head
e. atmospheric pressure has no bearing on static water
head
Preferably, dynamic pumps should be located
a. directly under the liquid source when suction lift is
e. below the liquid source when suction head is involved
involved
b. above the liquid source when suction head is involved
c. above the liquid source when suction lift is involved
,d. at the liquid source level when suction lift is involved
e. below the liquid source when suction head is involved
The vertical distance from the liquid surface up to the
pump centre-line plus the vertical distance from the pump
centre-line up to the surface of the liquid in the discharge
tank is
e. total static head
a. static discharge head
b. static suction head
c. suction lift
d. total discharge head
e. total static head
The ditterence between static suction head and static dis-
charge head is
a. total static head
a. total static head
b. static discharge head
c. static suction head
d. equivalent head
e. dynamic head
When a pump discharges into a vessel operating at 300
kPa, the 300 kPa is referred to as
a. dynamic head
b. equivalent head
b. equivalent head
c. discharge head
d. friction head
e. total static head
The total static head of a pump
a. is the capacity of the pump
,b. is the ditterence between the static suction head and
the static discharge head
b. is the ditterence between the static suction head and
c. is the discharge pressure in metres
the static discharge head
d. is all the parts of the pump casing
e. is the discharge head of the pump
When a reciprocating pump discharges while its piston or
plunger moves in only one direction, it is termed a
a. positive displacement unit
b. single acting unit
b. single acting unit
c. dynamic unit
d. double acting unit
e. duplex unit
Centrifugal pumps convert rotating mechanical energy
into kinetic energy then
a. discharge the kinetic energy
d. into potential energy in the form of pressure
b. back to mechanical energy
c. absorb the energy
d. into potential energy in the form of pressure
e. into centrifugal force
A hot water heating system circulator should
a. be directly coupled
b. have its own vibration-free base c. be very quiet in operation
c. be very quiet in operation
d. develop an extremely high ditterential pressure
e. not run continuously
The capacity of a centrifugal pump
a. varies with discharge pressure
, b. can be altered by speed variation only
c. indicates that the unit is a positive displacement type
d. should be varied by suction valve manipulation a. varies with discharge pressure
e. is fixed and can only be altered by changing the im-
peller
Centrifugal pump power requirements are decreased
when
a. discharge pressure is decreased
b. the litres moved per minute is decreased
b. the litres moved per minute is decreased
c. the casing pressure drops
d. the discharge velocity is high
e. the discharge head is at minimum
A rotary pump
a. is a variety of dynamic unit
b. never has discharge pulsations c. should be equipped with a relief valve
c. should be equipped with a relief valve
d. has the highest capacity of any pump
e. never requires cylinder lubrication
When starting-up a rotary pump you must be sure that
the
a. discharge valve is closed
b. discharge valve is open
b. discharge valve is open
c. pump is filled with air
d. pump is at the correct temperature
e. pump suction valve is closed
Rotary pumps:
1. are high pressure pumps
2. must be primed
