Bearing Misc.

Question 0

Pitting

Answer 0

Arc damage in a stationary bearing

Question 1

Fluting

Answer 1

Arc damage in a rotating bearing

Question 2

Electric arc

Answer 2

-an electric arc jumping across the clearance inside the bearing and leaves a track on a surface

Question 3

Causes of arcing

Answer 3

• welding on the supporting structure next to the bearing with the ground attached at the opposite side of the bearing
• electric charge s can develop in the shaft and housing of high-speed machinery

Question 4

Operating above recommended load.

Answer 4

-shortens life by 90%

Question 5

Operating above recommended speed

Answer 5

Reduces life by 50%

Question 6

Lip Seal

Answer 6

• makes a seal by pressing the seal lip against the seal surface
• its the initial light contact pressure before start up
• temperature restricted to -40 to 200 degrees C

Question 7

External seal

Answer 7

• a seal on the bearing housing

- Advantage of offering a wide selection

Question 8

Integral Seal

Answer 8

• seal attached to the bearing

- has the advantage of being cheap and more compact than external

Question 9

V-ring

Answer 9

• attached to the shaft and contacts the surface of the housing
• 15 meters per second the lip will lift
• low speed seal can operate with a large amount of axial movement

Question 10

Mechanical seal

Answer 10

• a stationary ring and a rotating ring made out of carbon

- leak proof

Question 11

Split Joint Pillow Block

Answer 11

-gib joint can handle the greatest side load

Question 12

Unit Pillow Block

Answer 12

-the eccentric collar must be tightened in the direction of rotation

Question 13

Temperature is a result of what?

Answer 13

• Friction
• how fast the heat is dissipated
• heat transferred from the outside

Question 14

How much hotter could the rolling elements be compared to the outside surface when you check it?

Answer 14

20 degrees C, add another 10 degrees for the inner ring

Question 15

High amperage reading?

Answer 15

-abnormal load on machine

Question 16

Sounds from a bearing

Answer 16

• loud hollow noise could mean too much clearance
• high pitch whine could mean too little clearance
• growling noise could mean rollers and raceways are deteriorating

Question 17

Spalling

Answer 17

-the pitting and flaking that occurs from the micro-cracks in the loaded zone as the rolling element continuously goes through the loading and unloading zone

Question 18

Transducer

Answer 18

-a device that picks up the vibration and converts it into an electrical signal to give a reading

Question 19

Oil Analysis

Answer 19

• darkened oil indicates oxidation and means the oil should be changed
• sludge and acids in the oil is advanced oxidation and indicates a need for short intervals in oil changes

Question 20

Issues that could cause High Temperature

Answer 20

• lubrication issues
• a seal rubbing too hard
• bearing is failing
• increase in load or speed
• additional heat from an outside source

Question 21

What split joint pillow block can handle the greatest side load?

Answer 21

The Gib

Question 22

External rubbing seals?

Answer 22

-Lip, v-ring, felt

Question 23

External non-rubbing seal?

Answer 23

• Radial Labyrinth
• Axial Labyrinth
• combo Labyrinth
• seal washers
• flinger

Question 24

Locating ring (fixing or stabilizing)

Answer 24

-On fixed bearing at the drive end

Question 25

Unit pillow block Eccentric locking collar

Answer 25

-tightened in the direction of rotation