View
226
Download
2
Category
Tags:
Preview:
Citation preview
FWM Project
Ball Bearing Study- Steel Balls –vs- Ceramic Balls
FWM Project- Surface
Ball Bearing Contact SurfacesSurface Roughness:Raceway~ 3AABall ~ 0.1- 1.0 AA
Surfaces are ground, honed and lapped.
FWM Project- ContactGeneralized Hertz Contact Case
distancesdirection principle arey andx
,
12
3 2
122
where
b
y
a
x
ab
Q
2
22*
3
1
2
22*
3
1
2
22*
11
2
3
,
11
2
3
11
2
3
EE
Q
lyadditional
EE
Qbb
and
EE
Qaa
II
I
I
II
I
I
II
I
I
Steel-Steel Cermic-Steel
• Ball Bearings are referred to as “anti-friction” bearings because of the small amount of friction.
• Discuss sources of friction and relative amounts (effect of lubrication)
• Wear will not occur if there is proper lubrication• Discuss contact fatigue, Weibul charts and
method to calculate the L10 life of ball bearings
FWM Project- Friction, Wear, Contact Fatigue
• Discuss the differences in the minimum film thickness required for each material (based on composite surface roughness)
FWM Project- Elastohydrodynamic Lubrication
• Discuss the differences found between steel-steel and ceramic-steel contacts
• Compare with industry test results
• Make determinations on why the predictions do or do not match test results
FWM Project- Summary
Recommended