Alb Mod Anti Friction A

Question 1

Anti-friction bearings commonly have their inner ring sitting on a shaft when mounted. This inner ring is made of:

Answer 1

Hardened high-grade steel

Question 2

The surface the rolling members roll on is ground to a fine finish to reduce friction. It is called a:

Answer 2

Raceway

Question 3

The outer ring is similar to the inner ring except that it sits in a _____ when mounted

Answer 3

Housing

Question 4

The rolling members support the load and ideally should roll and not slide, skid or drag. This ensures two things: (2)

Answer 4

• Saves power

- Reduces wear

Question 5

The cage that holds the rolling elements can be mounted in 3 ways: (3)

Answer 5

• Mounted to inner ring
• Mounted to outer ring
• Free of both rings

Question 6

What are the three functions of a cage or separator? (3)

Answer 6

• Prevents elements from rubbing each other
• Pushes elements through unloaded zone
• Guide elements (with minimum friction)

Question 7

What are three factors that affect a bearings ability to carry a load? (3)

Answer 7

• Area of contact
• Direction of load
• Loaded zone

Question 8

Under a ball bearing, the area of contact is circular until a load applies to the ball, then it is:

Answer 8

Elliptical

Question 9

Under a roller, the area of contact is a narrow rectangle. The size of these areas becomes larger as the size of the ____ increases

Answer 9

Rolling element

Question 10

The larger the area of contact, the larger the _______.

Answer 10

Load capacity.

Note: this is because the load is distributed over a larger area

Question 11

If the nominal contact angle is 0° and the load carries at 90° to the shaft axis, the bearing is a ____ load bearing

Answer 11

radial load bearing

Question 12

If the nominal contact angle is 90° then the load is in line with the shaft axis and the load is _____

Answer 12

Axial or thrust

Question 13

If the nominal contact angle is between 0° and 90° then the load acts at an angle to the shaft and is considered:

Answer 13

Combination radial and axial

Question 14

The loaded zone is the:

Answer 14

Section of raceway where rolling elements are under load

Question 15

Loading zone also depends upon the amount of:

Answer 15

Internal clearance or preload

Question 16

A larger load zone means that more elements are supporting the load, thus:

Answer 16

Increasing load capacity

Question 17

This bearing is the most common type of ball bearing. Mainly intended to support radial loads, it can also support combination loads as well as moderate axial loads in both directions. Has a contact angle the changes with the direction of loading, and tolerates very little misalignment.

Answer 17

Single row deep groove ball bearing (or Conrad bearing)

Question 18

The name Conrad comes from:

Answer 18

The method that Conrad invented for loading the balls into the bearing

Note: allows you to easily remove the balls to inspect raceways on a failed bearing by clamping the bearing in a vice after cutting the cage

Question 19

The deep groove ball bearing is available in a maximum capacity series. The bearing is similar to a regular deep groove ball bearing, except that it:

Answer 19

Is assembled with more balls

Question 20

When compared to a regular deep groove ball bearing, the max capacity deep groove ball bearing has a higher radial load capacity, but a smaller:

Answer 20

Axial load capacity

Note: the max capacity version is also more sensitive to misalignment

Question 21

This type of bearing provides a higher radial load capacity without increasing radial dimensions. However, because it has filling slots, it’s restricted to mainly radial loads

Answer 21

double row deep grove ball bearing

Question 22

This type of bearing is used when alignment is impractical or impossible to maintain, often due to shaft deflection. Can support small thrust loads, and has speed ratings similar to a single row deep groove ball bearing. Also required for shafts that operate at high speeds with extreme accuracy

Answer 22

Internally self aligning ball bearing

Note: these bearings an never exert a bending influence on the shaft

Question 23

This type of bearing has a spherically ground outer ring that mounts in a special housing. Allows for misalignment, but does not perform well with shaft wobble.

Answer 23

Externally self aligning ball bearing

Question 24

Compared to externally self aligning bearings, internally self aligning bearings: (3)

Answer 24

• support smaller axial loads
• Same speed rating
• More suitable for shaft wobble

Question 25

Single row angular contact bearings can accommodate what kinds of loads?

Answer 25

radial and thrust

Question 26

The axial load capacity of a single row angular contact bearing increases with an increase in the:

Answer 26

Contact angle Note: these are available in various contact angles

Question 27

The low shoulder of a single row angular contact bearing allows you to install a greater number of balls, which:

Answer 27

Gives higher load ratings

Question 28

With single row angular contact bearings, you can move the inner or outer rings axially, which adjusts:

Answer 28

Internal clearance or preload

Question 29

Single row angular contact bearings are available in both ___ and ___ series

Answer 29

Standard and precision.

Question 30

Because of the design of a single row angular contact bearing, if the bearing isn't mounted as a pair, thrust must be:

Answer 30

In only one direction

Question 31

With single row angular contact bearings, both the face to face and back to back arrangements can handle:

Answer 31

Reversing axial loads

Question 32

The tandem arrangement of single row angular contact bearings can handle thrust in only one direction, but can handle more:

Answer 32

Radial loads (vs face to face or back to back)

Question 33

In what arrangement of single row angular contact bearings do you hold the shaft more rigidly in angular alignment?

Answer 33

back to back

Question 34

The double row angular contact bearing offers these three features: (3)

Answer 34

- Takes heavy radial and axial loading in both directions - Speed rating is lower than Conrad or single row angular - Cannot tolerate any misalignment

Question 35

This type of bearing can only be used for combination or axial loads, can handle reversing thrust loads, is a separable bearing, can be made with more balls, and is made of uniquely shaped raceways that are made of circular arcs which resemble a gothic arch

Answer 35

Four-point angular contact bearing

Question 36

The four point angular contact bearing has a narrow width, and occupies less space than a pair of:

Answer 36

Single row angular contact bearings

Question 37

This bearing is designed for pure thrust load only. Can only accommodate half the speed limit as a radial load bearing, because at high speeds, centrifugal forces spin the balls out of the races.

Answer 37

Ball thrust bearing

Question 38

With a ball thrust bearing, the non-self aligning ball thrust bearing cannot tolerate:

Answer 38

angular misalignment between the shaft and housing

Question 39

Cylindrical roller bearings are separable in both directions. Since the bearings separate axially, they can support only a pure:

Answer 39

Radial load

Question 40

An angle ring with a cylindrical roller bearing can prevent:

Answer 40

axial movement in one direction

Question 41

The cylindrical roller shape has a larger area of contact than a ball bearing of the same diameter, giving it a higher:

Answer 41

load capacity Note: can also be increased further by increasing the number of rollers

Question 42

Cylindrical roller bearings are available in a ______ for very heavy thrust loads

Answer 42

thrust configuration

Question 43

Needle bearings are available in a variety of types. the three most common types are bearings with: (3)

Answer 43

- No cage/inner ring - a drawn steel cup and no inner ring - machined inner and outer rings

Question 44

The cageless design of needle bearings are limited to: (2)

Answer 44

- Slow speeds - oscillating motions Note: this is because the rollers rub into each other

Question 45

The drawn steel cup design of needle bearings can be operated at high speeds, and must be fitted to a:

Answer 45

Smooth, accurately machined housing. Note: depends on the bore for support

Question 46

The machined inner and outer ring design of needle bearings saves the shaft from wearing against the _______. It can be operated at high speeds.

Answer 46

rolling elements Note: also takes up more radial space than the other two common styles

Question 47

These types of bearings are assembled to support radial loads only. They are similar to cylindrical rollers, except that they are 2.5 to 10 times as long as their diameter. Can be used where space is limited, and offer a high load capacity.

Answer 47

Needle bearings

Question 48

The two parts of the single row tapered roller bearing are the: (2)

Answer 48

- Inner ring, aka cone | - Outer ring, aka Cup

Question 49

The cage, cone, and rollers of a tapered roller bearing are all on the same assembly, and installed into:

Answer 49

-Cup, or outer ring

Question 50

The tapered raceways of a tapered roller bearing allow it to:

Answer 50

Carry heavy combined radial and thrust loads in one direction Note: can tolerate little misalignment

Question 51

You can use a pair of tapered roller bearings to: (2)

Answer 51

- Accommodate Reversing loads | - Prevent separation

Question 52

With a tapered roller bearing, this type of cage allows for closer roller spacing and therefor provides a higher maximum load:

Answer 52

pin-type cage

Question 53

These tapered roller bearings are matched pre-set assemblies, so the components are not interchangeable. Used for heavy applications, can be double cone or double cup.

Answer 53

Double row tapered roller bearings Note: can be made with a tapered bore

Question 54

This version of the double row tapered roller requires a cone spacer, and can be used as a floating assembly in a housing

Answer 54

double cup assembly

Question 55

This bearing has barrel shaped rollers which provide a wide load contact area, provides combined thrust (both directions) and radial load capacity, is internally self aligning without reducing bearing capacity. Most commonly made in a double row configuration, it's also available in a single row design with high radial load capacity but very little thrust capacity

Answer 55

spherical roller bearing

Question 56

This type of bearing was designed to solve bearing failure problems in paper mills. It's used in applications requiring better floating bearings. It is radially compact, but with some misalignment capability. Can allow axial displacement more than any other bearing, and for that reason is not recommended for thrust loads.

Answer 56

CARB or Compact Aligning Roller Bearings

Question 57

CARB bearings or compact aligning roller bearings have more axial displacement than any other bearing, up to ____ % of its width.

Answer 57

20% of its width

Question 58

The speed of a bearing depends on how smoothly it rolls. The things that affect the smoothness are: (5)

Answer 58

- Type and size of rolling element - Precision of bearing - Type of cage - Type and method of lubrication - Type of seal

Question 59

The dynamic load rating of a bearing depends on the load distribution. the load distribution depends on: (3)

Answer 59

- size of rolling element - Type of bearing - Loaded zone

Question 60

The loaded zone can be increased by: (2)

Answer 60

- Reducing internal clearance | - increasing contact angle

Question 61

Dirty environments can lessen the life of a bearing. You can counter this with integral seals. What are the two types of integral seals? (2)

Answer 61

Non-rubbing seals (shields) | Rubbing seals

Question 62

For a bearing that will withstand moisture, you should pick one with: (2)

Answer 62

- Stainless parts | - Brass or polyamide cage

Question 63

For a quieter running bearing, you want a bearing that is:

Answer 63

Made to closer tolerances

Question 64

High speed machine tools require minimum deflection, which is achieved by using bearings that are:

Answer 64

Made to closer tolerances

Question 65

Most standard bearings are stable up to _____°

Answer 65

120°C or 250°F

Question 66

How tightly or loosely a bearing fits in its mount directly affects its: (2)

Answer 66

- Performance | - Length of life

Question 67

The correct fir ensures that the bearings: (4)

Answer 67

- Rings do not spin on their seats - rolling elements don't skid or bind - Inner ring not so tight it cracks from hoop stress - Preload is present

Question 68

The tolerance for any dimension is the :

Answer 68

total permissible variation on size

Question 69

Fit is the term for the:

Answer 69

Range of permissible tightness or looseness of mating parts

Question 70

You use ____ or ____ to ensure you have the proper fit between the shaft and inner ring, and the bearing house and the outer ring.

Answer 70

Tolerance codes or fit codes

Question 71

The letter in the tolerance code has 3 pieces of information: (3)

Answer 71

- Upper case letter indicates tolerance for a hole - Lower case letter indicates tolerance for a shaft - The letter also tells us the tolerance position

Question 72

When interpreting the fit tables, you require the: (3)

Answer 72

- Operating conditions - Bearing type and size - type of ring loading

Question 73

The types of ring loading that are available are: (3)

Answer 73

- Rotating - stationary - Intermediate

Question 74

When determining fits, you should use a micrometer that reads up to ____" in detail

Answer 74

0.0001"