Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Test Review > Positive And Non Positive Displacment Pumps And Fans > Flashcards

Positive And Non Positive Displacment Pumps And Fans Flashcards

1
Q

Which of the following pumps is not dynamic:

Reciprocating
Centrifugal
Mixed flow
Axial flow

A

Reciprocating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When liquid is vaporized when pumping, what will happen?

A

Cavitation will occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The capacity of the pump varies __________ when operated at a constant speed?

A

Directly with impeller diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When the pump inlet is above the level of the liquid in the supply reservoir, the pump has a suction ________?

A

Lift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What source of energy is available to allow liquid to enter a pump with suction lift?

A

Sucking action of the impeller to start the flow and atmospheric pressure to keep the flow moving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The impeller that helps push the liquid to the pump inlet?

A

Inducer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The NPSH available must be ______ or higher then the NPSH required to prevent cavitation?

A

10% or more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pumps convert mechanical energy to______?

A

Hydraulic energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Diffusers in pumps are mounted where?

A

Around the impeller

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Gauge pressure is?

A

Atmospheric pressure minus absolute pressure

Absolute pressure is 14.7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Cavitation can be caused by ?

A

An increase in intake velocity or to large of a suction lift.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Bernoulli’s principle relates to dynamic pump systems in that they have?

A

Pressure head from the pressure acting upon the liquid

Velocity head from the speed of the liquid through the pipe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

As pressure is increased, the boiling point of the liquid _______?

A

Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pump performance curves are based on handling ________ water, and a specific gravity S.G of _____?

A

Cold

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Friction losses through pipes depend on:

A

Inside diameter of the pipe
Fluid velocity
Surface finish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What things can happen if you install the pump with the wrong impeller rotation?

A

Inadequate discharge
Excessive power consumption
Pump won’t deliver fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

An excessive suction lift can cause?

A

Insufficient atmospheric pressure at the intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A suction piping condition to avoid is?

A

Reduced or restricted pipe diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Water hammer is a result of?

A

Opening and closing valves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Hydraulic slap is the result of ?

A

Check valve closing to quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Dynamic pump wear rings should be replaced when?

A

The clearance is increased 3 times the initial clearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The screws of multiple screw pumps can use _______ to help stop the rotors from contacting each other.

A

The positon of timing gears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Pump motor power consumption may increase if the?

A

Pump packing gland is over tightened

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Recirculation of fluid in the pump causes ?

A

Vortices and cavitation to be created

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Changing impeller’s diameter effects?

A

Pump capacity and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The dial indicator touching the face of a shoulder on a shaft will tell you?

A

Shaft end float

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When blinding piping for pump removal, blinds should be placed on the down stream of the suction valve and upstream of the _________ valve

A

Discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Mechanical seal faces that have uneven wear patterns on them will indicate ?

A

Misalignment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Valve packing controls leakage between?

A

Plunger and chamber or between piston and cylinder wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Internal wear rings can be removed by?

A

Welding on the inside diameter of the ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

When taking a back pullout design centrifugal pump apart, you should first refer to the ________?

A

Manufactures instructions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

If you need to break a partial vacuum when taking a positive displacement pump apart, you need to ______?

A

Remove the drain plug from the casing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Pump shaft runout is measured with?

A

Dial indicators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

When rebuilding a centrifugal pump, the last thing you would check would be if?

A

The rotor turns over

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is used in a positive displacement pumping circuit to help eliminate vibrations and absorb cyclical flow variations?

A

Pulsation dampener

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

On a vertical plunger pump, the pump is attached to the ______?

A

Crosshead

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Which of the following vane pumps use an oval rotor in a concentric housing?

Flexible
Balanced
External
Unbalanced

A

External

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which of the following reciprocating pumps can run dry?

Plunger
Single acting piston pump
Double acting piston pump
Diaphragm pump

A

Diaphragm pump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

High pressure diaphragm pumps (up to 5000psi) use _________ to activate them?

A

Hydraulic fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

A flexible pump uses a _________ to squeeze the flexible tube?

A

Compression ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

When a relief valve is forced open because of high pressure in a pumping system, the liquid is returned to the ______?

A

Suction side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What type of check valve would be most suitable for liquids contains solids?

A

Flap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

A sand which diaphragm on a hydraulically activated diaphragm pump is used to help prevent product escape by using a ________ sensor that lets you know when 1 diaphragm leaks.

A

Rupture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Which type of pump requires timing gears?

Gear
Lobe
Flexible vane
External vane

A

Lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Which pump has a cam inserted between the discharge and inlet ports?

A

Flexible vane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Which pump has an eccentric rotor?

A

Flexible liner

47
Q

The impeller with the lowest specific speed is?

A

Radial flow

48
Q

Inducers have ________ flow?

A

Axial

49
Q

In a volute pump, the impeller can be reduced by _______% before hydraulic losses affect pump efficiency?

A

20

50
Q

The type of impeller that has a double curvature vane is the?

A

Francis

51
Q

The multi stage barrel pump(double casing) have what bennefit?

A

Stop leakage to atmosphere of high pressure pump systems

52
Q

Double suction single stage pumps have a single suction inlet that splits to allow ____________?

A

Flow to both sides

53
Q

Wear rings will last longer by?

A

Making both rings out of a hard material when immersed in a abrasive liquid.

Being immersed in a clean pumping liquid.

54
Q

A combination disc and drum balancing device will?

A

Balance out the suction and discharge pressure helping lower axial thrust.

55
Q

Calculate the pressure of a column of water 30 feet tall.

PSI = ft X .433 x S.g

SG water is 1

A

PSI = 30 x .433 X 1

Psi = 12.99

56
Q

Calculate 40 ft of oil with a s.g .8 to the equivalent height of water?
Ft = psi / .433 x S.G
PSI = ft x .433 x S.G

A

40 x .433 x .8 = 11.86 psi

11.86/.433 x 1 = 32 ft of water

57
Q

Convert 54 psi of oils with a s.g of .9 to the ft of head of oil?

Ft = psi / .433 x s.g

A

54 / .433 x .9
54 / .3897 = 138.6 feet

58
Q

A pump is supplying a plant with water 300ft above it. The pump needs to be running with a pressure of 200 psi after supplying the water to the 300 ft level what will the discharge pressure at the pump be.

A

Psi = 300ft x ,433 x 1 = 129.9

Psi + running psi = total psi

129.9 + 200 = 329.9

59
Q

A pressure gauge reads 350 psi. If it was pumping water what would the feet of head be?

A

350 / .433 x 1
350 / .433
808 feet

60
Q

A pressure gauge reads 500psi. If it was pumping oil with a s.g of .75 what would the feet of head be?

A

500 / .433 x .75
500 / .32475
1540 feet of head

61
Q

A pump displaces 350 psi . Line pressure at the plant is 100 psi. How much higher is the plant above the pump?

A

350 - 100 = 250 psi.

250 / .433 x 1
250 / .433
Equals 577 feet above the pump

62
Q

If you were using a pump graph what informations would not be available?
Feet of head
NPSHa
Brake HP
Gpm

A

NPSHa
Net positive suction head available

63
Q

When dealing with fans, 1psig will support ________ column.

A

27.7” of water

64
Q

Static pressure developed by a fan is?

A

Pressure that air exerts on the inside of the duct walls

65
Q

Velocity pressure is ?

A

Equal to total pressure minus static pressure

66
Q

Air travelling through a restriction will show what changes?

A

Decrease in static pressure, increase in velocity pressure

67
Q

All fan pressures can be read with?

A manometer hooked up to the side of the ducting and the other end hooked up to atmospheres

Manometer hooked up to the side of the ducting and the other end inside the ducting facing the air flow

The manometer hooked up inside the ducting and the other end open to the atmosphere

A

You need to do all of the above and read the fan pressures

68
Q

When the damper is closed, all pressure in the system is changed to?

A

Static

69
Q

All fans need to be _________ to help stop arcing through bearings?

A

Grounded

70
Q

Centrifugal fans

A

Have radial flow

Use forward curved and backward curved incline blades

Have a scroll

71
Q

When fans are mounted in series, they

A

Increase pressure

72
Q

The centrifugal fan changes velocity pressure to static pressure in the_______

A

Scroll

73
Q

Forced draft is when the fan is controlling the air flow into the furnace and_______

A

Pressurizes the furnace

74
Q

The velocity of the air in the fan can be increased (while running) with which type of blades?

A

Variable pitch

75
Q

Open wheel radial blades can handle

A

Small wood blocks
Silage
Paper trim

76
Q

An inlet bell with an internal guide vanes will help centrifugal fans ________ air swirl

A

Decrease

77
Q

The use of diffuser rings in centrifugal fans should not be used?

True or false

A

True

78
Q

Axial fans compared to radial fans?

A

Require less power at the maximum air delivery

79
Q

Cooling towers can use

A

Atmospheric pressure for the air flow

Forced draft

Induced draft

80
Q

On fan discharge piping you need a straight section of ducting to help

A

Velocity pressure

Laminar flow

81
Q

Vibration isolators are needed to

A

Help absorb mechanical air flow imbalances

Be mounted between the baseplate and the foundation

Cusion vibrations

82
Q

Valves are made of what materials?

A

Bronze

Cast iron

Stainless steel

Aluminum

83
Q

Valve ratings tell you the working pressure when the valve is used for steam or water and oils and gas

True or false

A

True

84
Q

What does CWP stand for

A

Cold working pressure

85
Q

Gate valves can come in rising stem and non-rising stem. These valves are not used used for throttling because?

A

Wire drawing

Erosion

86
Q

The large butterfly valve uses a power actuator to rotate the disc because of the large pressure differential across it?

A

True

87
Q

Needle valves are used for pre ice fluid control?

A

True

88
Q

Globe valves have the fluid change directions _____ time through it?

A

2

89
Q

Balance valves can be the single or double seated type and require less force to operate then conventional globe valves

A

True

90
Q

Diaphragm valves are used in corrosive and toxic fluids because they can produce a bubble tight and drip tight closure?

A

True

91
Q

Check valves prevent reverse flow through them by

A

Reverse of fluid flow closing the ball or flap

Gravity acting on the ball or flap

92
Q

Pressure relief valve start opening at a preset pressure which is called ________ pressure?

A

Cracking

93
Q

Pressure override is the difference between ________ and __________ pressure

A

Cracking and full flow

94
Q

Rupture disc relief valves rupture at a pre set pressure and are used with a _______ valve to stop the fluid flow.

A

Gate or plug

95
Q

Large hand and wheel valves (for two handed operation) usually have a worm and wheel gear reduction to get the mechanical advantage to open the valve?

A

True

96
Q

Limit switches are employed with cylinder actuators to confirm full travel.

A

True

97
Q

Lapping to mating surfaces on valves allows the valve to have a positive seal and no leakage.

A

True

98
Q

When lubricating valve stem packing, also apply a few drops of oil onto the valve stem and any exposed threads. This will greatly extend the life of the valve packing.

A

True

99
Q

When repacking valve stuffing boxes, you will add oil after packing some of stuffing box making sure the slits are 90 degrees from each other

A
100
Q

All valves must be checked for leakage. The valves would be tested according to the valve class and simulate the valve operating conditions.

A

True

101
Q

The bonnet is the part of the valve thru which the stem extends. It contains the means for sealing the fluid in the valve.

A

True

102
Q

Environmental pollution is any discharge of material or energy in the:

A

Land

Air

Water

103
Q

The most efficient approach to pollution control is?

A

To change the process

104
Q

If there is acid effluent in water treatment, the acid must be neutralized with chemicals

A

True

105
Q

Air particles are removed with _________ which have the highest removal efficiency?

A

Bag house

106
Q

Cyclones rely on _______ to help separate out particulates:

A

Inertial forces

Centrifugal forces

Gravity

107
Q

Cyclones are less efficient when the dust density is _______

A

High

108
Q

The cleaned air is expelled from the _______ of the revers flow cyclone?

A

Top

109
Q

When using a bag house, you will choose the type of filter bags based on?

A

Temperature
Chemical composition of the gas
Type and make up of particulates

110
Q

When reconditioning (cleaning) the filters of a bag house, you can _________ to do the job

A

Mechanically shake them

Use reverse air flow

Use pulse jet

111
Q

To attract particles when using electrostatic precipitator, you would use a ________ charged electrode and a _______ charged plate which attracts the particles.

A

Negative

Positive

112
Q

Dry dynamic precipitators have the particle laden gas stream driven against the ________ and then deposited into the hopper

A

Fan blades

113
Q

A scrubber is a ______collector and can use a _______ or ________ to disperse the droplets?

A

Wet

Fan

Pump

Test Review (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions