Bearings

Question 1

Antifriction bearings are used where?

Answer 1

Low starting friction is required

Question 2

What type of bearing can support an axial load

Answer 2

Thrust bearing

Question 3

Excessive pressure in time show up as spotty uneven wear especially in sleeve bearings, this is a stress called

Answer 3

Bending stress

Question 4

When a shaft reaches its critical speed the…

Answer 4

Vibration becomes uncontrolled

Question 5

The loosest class of fit of a shaft in a bearing is

Answer 5

Running and sliding fits

Question 6

The tightest class of fit of a shaft in a bearing is

Answer 6

Force fits

Question 7

It is common practice to provide grooves on the inside surfaces of a blank blank bearings to distribute lube

Answer 7

Plain journal

Question 8

To distribute lube plain bearing journals may have

Answer 8

Axial and circumferential grooves

Question 9

To keep lube in and dirt out plain journal bearings may have what

Answer 9

Bearing seals

Question 10

Common variations of the split bearing are blank and blank

Answer 10

Half bearing and the multipart bearing

Question 11

Some precision bearing inserts are

Answer 11

Trimetal inserts

Question 12

Crush means what to a bearing

Answer 12

Materials that are slightly larger than the bore

Question 13

Spread means what to a bearing

Answer 13

Slight increase in diameter of bearing than bore

Question 14

A bearings ability to adjust to misalignment without failing is called

Answer 14

Conformability

Question 15

A bearings ability to absorb dirt or other particles is called

Answer 15

Embeddability

Question 16

What has good shock and wear resistance

Answer 16

Aluminum bronze alloy

Question 17

A common rule of thumb is to replace high speed equipment bearings at blank the amount of their original clearance

Answer 17

Twice

Question 18

Groove width is approximately blank it’s depth

Answer 18

Twice

Question 19

The grooves depth should not be more then what of the wall thickness of the bearing

Answer 19

One third

Question 20

What part of a bearing carries none of the load and is therefore subject to little wear

Answer 20

The cage

Question 21

Why is oil used in high speed operations

Answer 21

Oil dissipates heat better

Question 22

Two or three letters indicate what on a bearing

Answer 22

Type and construction, and OD and width dimensions

Question 23

A factor that influence the running accuracy of bearings are

Answer 23

Radial runout, the allowable out of roundness of both inner and outer rings

Question 24

Which of the following identifies the most precise standard ball bearing

Answer 24

ABEC-9

Question 25

Bearing life is closely related to these factors

Answer 25

Speed load and fatigue

Question 26

Antifriction bearings are limited by

Answer 26

Their lack of resistance to fatigue

Question 27

What are the most frequent causes of premature bearing failure

Answer 27

Inadequate or improper lube

Question 28

The fixed bearing also carries the

Answer 28

Thrust load

Question 29

Floating bearings allow what kind of movement

Answer 29

Axial movement

Question 30

What kind of bearings resist radial loads thrust loads of combined loads from any direction

Answer 30

Double row, angular contact bearings

Question 31

What kind of bearing provides the same capacity as a larger conventional bearing but saves space

Answer 31

Staggered roller bearing

Question 32

What type of bearings are intended for heavy loads and to operate at higher speeds

Answer 32

Cylindrical roller bearings

Question 33

What kind of bearings are designed to support high radial or combined axial and radial loads

Answer 33

Spherical roller bearings

Question 34

The outer ring of a bearing is called the

Answer 34

Cup

Question 35

What is the inner part of a roller bearing called a race or

Answer 35

Cone

Question 36

What do loose needle bearings not have

Answer 36

Inner race

Question 37

What type of bearing is used for high thrust loads and heavy shock

Answer 37

Tapered roller thrust bearing

Question 38

What kind of bearing is a self aligning bearing

Answer 38

Spherical roller

Question 39

What type of bearing is used for liner motion

Answer 39

Ladder bearing

Question 40

Takeups allows what kind of movement

Answer 40

Sideways movement

Question 41

A seal on a bearing must be able to preform at least one of two functions

Answer 41

Seal out dirt and retain lube

Question 42

A seals width is the

Answer 42

Overall thickness of the outer case

Question 43

When selecting a seal for a specific application what must be taken into consideration

Answer 43

Speed of the shaft surface in fpm

Question 44

Shafts must be ground or polished to a very fine finish for what kind of seal

Answer 44

Synthetic seal

Question 45

A spring closure ring is usually used to force the seal against the

Answer 45

Shaft

Question 46

Lightweight oil is used for what

Answer 46

High speeds and light loads

Question 47

The sump and the drained oil should be inspected for what

Answer 47

Metal particles

Question 48

The hardness of the grease is expressed by a number ranging from

Answer 48

0-6 the higher the number the harder the grease

Question 49

Enough grease should be used to fill the bearing from one third to

Answer 49

One half full

Question 50

In many cases bearing failures are due to hasty and

Answer 50

Improper installation procedures

Question 51

Misalignment of roller or ball bearings will

Answer 51

Appear to work ok but will have their life shortened considerably

Question 52

Some noises to listen for when the bearing is running is

Answer 52

A high pitched whine from interference or overload

Question 53

Excessive bearing loading can cause little indentations on each ball and in the bearing race called

Answer 53

Brinelling

Question 54

Immediately after cleaning a bearing give it a coating of what

Answer 54

Light oil