Bearing maintenance Flashcards Preview

2ed Year Millwright theory a > Bearing maintenance > Flashcards

Flashcards in Bearing maintenance Deck (12):
0

What is the temperature difference between the outer ring rolling elements and inner ring

The rolling elements are usually 20° hotter than the outer ring
The inner ring usually 30° hotter than the outer ring

1

What kind of noise should a good bearing make when heard without a stethoscope

Soft purring sound like a motherfucking pussy cat

2

What is meant by built in contaminants

Dirt that is introduced into the machine during assembly

3

What is meant by brinelling in a bearing

Impacted denting of the raceways

4

What are the two most common causes of vibration

Imbalance
Misalignment

5

Can all harmful levels of vibration be detected by hand

No most cannot be detected by hand at all (you will need other means of detection)

6

How can the condition of bearings monitored before they reach the last stage of deterioration

By taking vibration readings with the vibration data collector at regular intervals

7

What is the major cause of premature antifriction bearing failure

Contamination

8

Why is it important not to heat a bearing above 120°C

Pictures above 120°C can permanently distort the bearing

9

What is false brinelling

Dents worn into the raceway due to vibration of the rolling elements while the bearing is stationary

10

Was the main cause of lubrication breakdown

Heat

11

What are the two causes of electric arcing in bearings

Improper ground location when welding near a bearing


Static electricity