Plain Flashcards
What 2 types of load do plain support
Thrust
Journal
What is the difference between plain & anti friction bearings
Plain have no rolling elements
There are 3 types of radial load what are they
Stationary
Oscillating
Reciprocating
What is an oscillating load
The load shifts through an arc less than 180*
What is a stationary load
The load acts in one direction only
What is a reciprocating load
The load shifts 180*
What is the difference between a bushing and a bearing
Bearing is split bushing is not
Name 2 types of pre-lubricated bearings
Porous bronze Bronze matrix ( dry )
What 2 things are needed to maintain full film in hydrodynamic bearings
Minimum speed
Viscosity of lube
In a hydrodynamic bearing where is the oil inlet
In the unloaded area
In hydrodynamic what is oil whirl
An unsteady load at speed can cause oil whirl ( a wave like motion)
To stabilize oil whirl which 2 types of bearing can be used
Tilting pad
Lobed
When is a hydrostatic bearing needed
When a heavy unsteady load must be carried
Where speed is too low for hydrodynamic
Hydrostatic bearings depend on what for lubrication
Pressurized oil
What are some of the limitations of pre-lubed bushings
Poor heat distribution
No lube circulation
Not suitable for start/stop
Not suitable for high temp
Can you name 2 types of bushing
Wrapped
Solid
Floating
Water lubricated
What is the porosity of a porous bronze bushing
3-30%
On hydrostatic bearings what controls oil pressure
Restrictors are threaded in with different size orifices to control pressure
On an oil lift bearing what is the term used for the oil
Jacking oil
Hybrid bearings require 2 types of lube to operate
Hydrodynamic
Hydrostatic
What is the function of a thrust bearing
To hold a shaft axial lay
What are 3 types of thrust bearing
Flat plate
Tapered land
Tilting pad
What is fatigue resistance
Ability to resist cracking and flaking
What is embeddability
How a material will handle contaminants without failure
