Wastewater Study Guide

Front 1

The amount of energy in feet required to overcome resistance to flow in a pipe is called

Back 1

Friction Head

Front 2

The amount a liquid can be raised vertically by a given pressure is called

Back 2

Pressure Head

Front 3

The amount of energy in feet that a pump supplies to a liquid is called

Back 3

Pmp Head

Front 4

How many inches is a total vacuume at sea level?

Back 4

30 in.

Front 5

How many feet of water will equal the atmospheric pressure at sea level?

Back 5

34 in.

Front 6

The most widely used pump type in wastewater is

Back 6

Centrifugal

Front 7

What is used to stop air leakage into the casing around a pump shaft?

Back 7

Seals

Front 8

What assembly hold the lantern ring and packing?

Back 8

Stuffing Box

Front 9

The lantern ring is also known as the

Back 9

Seal Cage

Front 10

What device applies an even pressure to the packing such that it compresses tight around the pump shaft?

Back 10

Packing Gland

Front 11

Which centrifugal pump impeller type would usually be used for pumping medium sized solids?

Back 11

Semiopen

Front 12

Which centrifugal pump impeller type would be used for pumping large solids?

Back 12

Open

Front 13

Which centrifugal pump impeller type would typically be used for pumping clear wastewater?

Back 13

Closed

Front 14

Which part of a centrifugal puymp has the function of separation the high-pressure zone in the volute from the low-pressure zone at the impeller's eye?

Back 14

Wear Rings

Front 15

What is at the top of a stuffing box?

Back 15

Packing Gland

Front 16

What part of a pump houses the packing or the mechanical seal?

Back 16

The stuffing box

Front 17

Velocity (V) head is expressed mathmatically as

Back 17

V2/Vg

Front 18

When water from a dam flows through turbines, it converts elevated head into

Back 18

Mechanical Energy

Front 19

What is the only type of pump that can be operated against a closed valve?

Back 19

Centrifugal Pump

Front 20

The purpose of the lantern ring is to

Back 20

Distribute lubercation to the stuffing box

Front 21

What device serves the same function as the packing?

Back 21

Mechanical Seal

Front 22

The bearings are protected from water leaking out of the stuffing box by the

Back 22

Slinger Ring

Front 23

The "heart" of a pump is called the

Back 23

Impeller

Front 24

Hydraulics is the study of

Back 24

Fluids in motion and at rest.

Front 25

What is it called if the energy supplied to a pump is equal to the energy required for the liquid to be moved to a specific point?

Back 25

Pump Head

Front 26

The arrangement of pumps in series is primarily used to increase the

Back 26

Flow but keep the discharge head the same.

Front 27

The arrangement of pumps in parallel is typically used

Back 27

When head is not sufficent and more flow is required.

Front 28

What type of centtrifugal pump should be used when pumping wastewater with large solids?

Back 28

Single-suction with open or semiopen impellers.

Front 29

What type of pump would be most likely used for chemical sloutions?

Back 29

Diaphram

Front 30

An object doing work by virtue of its motion is called

Back 30

Kinetic Energy

Front 31

Water behind a dam and above a water treatment plant has energy by virtue of its elevation. This difference in elevation is called elevation head or

Back 31

Potential Energy

Front 32

Open impellers are usually used to pump water that contains

Back 32

Large Solids

Front 33

Which type of centrifugal pump can have water enter from two sides (double Suction)?

Back 33

Split Case Pump

Front 34

Which type of impeller is best to use for pumping water with low volumes of solids?

Back 34

Closed

Front 35

What type of pump has the ability to rotate its discharge 360?

Back 35

End Suction Pump

Front 36

A split-case pump has two equal smaller impellers placed on either side of two equal size large impellers. How many stages does this pump have?

Back 36

Two Stages

Front 37

The lowst pressure point in the pump is

Back 37

The center of the impeller

Front 38

Sleeve bearings that are used in a vertical pump's column may be lubricated by

Back 38

Oil Drip System

Front 39

The shaft's main funtion is to transmit _______from the motor to the impeller.

Back 39

Torque

Front 40

The purpose of roller bearings is to

Back 40

Reduce friction and heat.

Front 41

A horizontal load parallel to a pump shaft is called a

Back 41

Thrust Load

Front 42

A load, perpendicular to a pump shaft, applied to a bearing is called

Back 42

A Radial Load

Front 43

Which one of the following is not a component of a bearing?

Back 43

Rolling Pin

Front 44

All of the following cause bearing failure, but which one is the major cause of bearing failure?

Back 44

Poor lubrication practices

Front 45

When removing the volute case to the gasket from a pump, you should use

Back 45

Soft-faced hammer

Front 46

The impeller of a pump is prevented from turning on the shaft by a

Back 46

Key

Front 47

How should a pump's shaft be stored when not in use?

Back 47

Stored vertically, on end.

Front 48

The purpose of the shaft sleeve is to prevent

Back 48

wear at the eye of the impeller

Front 49

Before installing casing wear rings, they should be

Back 49

cooled

Front 50

To ease installation of impeller wear rings, they can be

Back 50

heated

Front 51

Before reinstalling a shaft sleeve or impeller, it should be cleaned with

Back 51

kerosene

Front 52

What should be used to clean an old bearing?

Back 52

Solvent

Front 53

The purpose of packing is to

Back 53

control water leakage along the pump's shaft.

Front 54

Most pump packing is composed of __________with ________ lubrication.

Back 54

Asbestos base, graphite

Front 55

The packing used for medium pressures and temperatures is most likely

Back 55

asbestos

Front 56

Packing used in high-speed pumps and temperatures greater than 450 degrees F should be made of

Back 56

metal braided with asbestos

Front 57

New packing rings should be staggered at

Back 57

90 degrees

Front 58

Packing is designed to

Back 58

wear and deteriorate with normal use

Front 59

Packing replacement is usually performed when

Back 59

no further tightening can be done on the packing gland

Front 60

Seal water used to cool and flush mechanical seals should originate from an external source for all the following circumstances except

Back 60

when potable water is being pumped

Front 61

When external seal water is used as a water source, what should its pressure be in relation to the volute pressure?

Back 61

10 to 15 psi higher

Front 62

What type of coupling is used when the coupled shafts are of two different sizes?

Back 62

Flange Coupling

Front 63

This type of rigid coupling is easy to install and remove.

Back 63

Split Coupling

Front 64

Which one of the following statements is FALSE?

Back 64

Most pumps are self-priming

Front 65

How often should amperage and voltage tests be performed on three-phase motors?

Back 65

At least every 3 months

Front 66

The purpose of lubrication is to

Back 66

increase torque

Front 67

Grease that is water resistant is made with

Back 67

Calcium

Front 68

What is the approximate reduction in oil's "life" for each rise in temperature of 20 degrees F over 140 degrees F?

Back 68

50%

Front 69

Lubrication used on bearings of line shaft turbines can be

Back 69

oil or water

Front 70

Excessive upthrust on line shaft turbines is caused by

Back 70

pumping too much water

Front 71

Under what conditions are regenerative turbine pumps used?

Back 71

high head conditions

Front 72

The screw pump is most effective for lifts that are LESS than

Back 72

30 feet

Front 73

Approximately how much flow increase in percent occurs when a two-flight screw pump is changed to a three-flight screw pump, all other things being equal?

Back 73

20%

Front 74

What type of centrifugal pump is the most common?

Back 74

radial-flow impeller

Front 75

The capacity of a centrifugal pump is related to total head

Back 75

directly

Front 76

As the total head on a system increases, the volume that a centrifugal pump delivers is reduced

Back 76

proportionately

Front 77

In wastewater treatment, nonclogging pumps are usually designed to pass solids that have a diameter of at least

Back 77

3 inches

Front 78

What type of centrifugal pump is used to ensure that a wet well's pump maintains sufficient prime?

Back 78

dry pit pump

Front 79

Typically, pumps used to return activated sludge, recycle trickling filtter effluent, or return digester supernatant would be

Back 79

recirculatioon pumps

Front 80

Besides providing the enclosure for the impeller, the volute case is also cast and machined to provide a seat for the

Back 80

impeller rings

Front 81

If a centrifugal pump with a single volute is operated LESS than ______ of its design capacity, an excess radial load will result, causing premature bearing failure.

Back 81

30%

Front 82

If a centrifugal pump with a single volute is operated MORE than ______ of its design capacity, an excess radial load will result, causing premature bearing failure.

Back 82

120%

Front 83

What material is usually used for centrifugal pump sleeves?

Back 83

brass

Front 84

Rigid couplings are most common on

Back 84

vertical mounted pumps

Front 85

A type of rigid coupling would be

Back 85

split coupling

Front 86

How much will a flexible disk coupling compensate for in angular movement?

Back 86

2 degrees

Front 87

How much will a flexible disk coupling compensate for in parallel misalignment?

Back 87

1/32 inch

Front 88

What will a flexible diaphram coupling compensate for in angular movement?

Back 88

4 degrees

Front 89

What will a flexible diaphram coupling compensate for in parallel misalignment?

Back 89

1/8 inch

Front 90

Which one of the following statements is FALSE concerning lantern rings?

Back 90

The lantern ring is placed above the stuffing box.

Front 91

When should a mechanical seal be replace?

Back 91

When leakage becomes excessive.

Front 92

What are the bearings called that maintain the radial positioning of a shaft?

Back 92

radial bearings

Front 93

What are the bearings called that maintain the axial positioning of a shaft?

Back 93

thrust bearings

Front 94

What are the bearings of choice for centrifugal pumps today?

Back 94

roller bearings

Front 95

What type of bearing can operate well against radial loads but can withstand only very low thrust loads?

Back 95

self-aligning, double-row ball bearings

Front 96

Pump bases with four anchor bolts usually require ______ for each bolt.

Back 96

a set of shims

Front 97

Centrifugal pump misalignment causes between ______ of all bearing failures.

Back 97

50% to 70%

Front 98

How much seal water does a mechanical seal require?

Back 98

1 or 2 drops every few minutes

Front 99

Centrifugal pump motor bearings should have a temperature of about

Back 99

180 degrees F

Front 100

How often should the temperature of centrifugal pump motor bearings be checked with a thermometer?

Back 100

once a month

Front 101

Inspection of the shaft and coupling alignment should be performed every ______ or immediately if problem signs develop.

Back 101

6 months

Front 102

Which one of the following statements concerning lubricants is FALSE?

Back 102

Lubricants eliminate corrosion.

Front 103

The best lubricant for cooling is most probably

Back 103

graphite

Front 104

The best lubricant that would dampen shocks to the pump is

Back 104

graphite

Front 105

What type of lubrication is best used on pump bearings for light to moderate, high-speed, horizontally shafted pumps?

Back 105

water

Front 106

Bearings should not be lubricated with this type of oil because as this oil begins to breakdown it forms acids.

Back 106

animal oil

Front 107

Pump bearings are usually designed to use grease lubricants that provide oil lubricant in

Back 107

a soap-like base

Front 108

If a pump fails to prime because the suction lift is too high, what is the best solution?

Back 108

Reevaluate the pump's requirements and correct the condition.

Front 109

If a pump loses its prime because the suction line has an air pocket, what is the best solution?

Back 109

Suction piping air bleed off valves should be open.

Front 110

What type of pump has little chance of losing its prime but has the disadvantage of having a lack of access for maintenance or repair?

Back 110

submersible pump

Front 111

What type of pump can handle materials that would typically clog or damage the pump's impeller but has the disadvantage of being less efficient?

Back 111

recessed impeller or vortex pump

Front 112

What type of pump can produce a high head but requires high maintenance if large amounts of solids are being pumped?

Back 112

turbine pump

Front 113

What type of pump adds energy to the fluid flow intermittently?

Back 113

positive displacement pump

Front 114

Diaphragm pumps do not work very well if they have to lift liquids more than about

Back 114

4 feet