Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
13 Cards in this Set
- Front
- Back
|
If a double row spherical roller bearing were sitting on a table top, where would you check for its internal clearance ? |
Using feeler gauges check the roller next to the top roller. That roller is considered to be the unloaded roller. |
|
|
What is the difference between Residual and running clearance ? |
Residual is when it is installed on the shaft.
Running clearance is after the bearing warm up to temperature. |
|
|
If you cannot hold your hand on the housing for at least one second, what is the minimum estimated temperature of the inner ring ? |
The housing surface is at least 60 degrees Celsius. So add 20 degrees Celsius for the outer ring and 10 degrees Celsius for the inner ring. That would equal 90 degrees Celsius. |
|
|
What is the difference between Brinelling and false Brinelling ? |
Brinelling is impact denting and makes the bearing useless.
False Brinelling is a round depression worn into the raceway by a roller member, caused by not using block support during transport. |
|
|
List two ways a machine could ingest contamination ?
|
- Dust entering the breather.
- Liquids entering through faulty seals. |
|
|
What are two sources of electric arcing in a bearing ? |
- Welding on the support structure next to the bearing with the ground attached at the opposite side of the bearing.
- Electric charges can develop in the shaft and housing of high speed machinery. |
|
|
What are two main advantages of rubbing seals over non-rubbing seals? |
The rubbing seals can keep out vapours, liquid, fine contaminants and retain lubricant, like oil. |
|
|
What are the three ways in which the seal lip is pressed onto a shaft in a lip seal ? |
- Garter spring pressing the lip to the shaft
- Resilience of the lip seal material combined with a light interference fit to the shaft.
- Gas or liquid pressure acting on the lip to press it towards the shaft. |
|
|
What is the most important factor in the handling of mechanical seals? |
Do not touch the mated surface. Oil from your finger will disrupt the film that creates the seal between the rotating and non- rotating elements. |
|
|
The fixed pillow block bearing allows for axial expansion.
True or false |
False |
|
|
How must eccentric collars be installed on a unit pillow block? |
The eccentric collar must be tightened in the direction of rotation in order to stay tight. |
|
|
Why would a spherical roller bearing be used in a pillow block rather than a cylindrical roller bearing ? |
It can handle axial load |
|
|
What needs to be done to a pillow block to control heavy horizontal radial load ? |
Weld support blocks against the pillow blocks. |
