Plain Bearings Flashcards
What are the two types of plain bearings?
Metallic and non-metallic
What are some types of metallic plain bearings?
Bronze
Copper
Aluminum alloy
Babbit (lead, silver)
What is the main advantage of a metallic plain bearing?
High load capacity
What is main advantage of non-metallic plain bearing?
Shock and vibration
What do bearings do?
Support motion and force.
What are the three types of motion?
Rotary
Linear
Combined
What is “critical factor” of plain bearing?
Load or (P) for pressure
What is major factor of plain bearing?
Speed or (V) for velocity
How deep should grease grooves be?
1/4 of thickness of bearing material
When is grease grooves necessary?
When the length of bearing is more than twice the diameter of shaft
What is “extreme service condition” of self lubricated plain bearings?
Heavy moisture content
Corrosives
Extreme temperatures
What is the temperature range of metallic plain bearings?
-200 to 900F
What are the three stages of lubricity on plain bearing?
Boundary
Mixed film
Full film
How can you increase lubricity?
Increase speed
Decrease load
Increase viscosity
What is resultant?
Load x velocity or (PV)
