3. Bearings And Seals Flashcards
all bearings are designed to preform what functions?
- provide support and alignment for a moving part
- reduce friction
- decrease wear
- provide a replaceable wear surface
radial loads act:
at 90* to the axis of shaft
axial loads act:
parallel to axis of shaft
what are the two basic classes of bearings?
- friction
2. anti-friction
what is bearing crush?
the press fit that seats the bearing halves after assembly
what are the 3 types of anti-friction bearings?
- ball
- roller
- needle
anti-friction bearings can be designed to absorb what kind of loads?
Axial
Radial
Combination of both
what are most common designs of roller bearings?
- Tapered
- plain roller
- spherical roller
- needle
the roller in a spherical roller bearing is shaped like what?
Barrel-shaped
how are ball bearings categorized?
the type of raceway each contains
what are seals commonly used for?
- keep fluids in
- keeps contaminates out
- hold pressure or vacuum
what are the two classed of seals?
- dynamic
2. static
where are static seals used?
where there are no moving parts
what are common types of static seals?
- O-rings
- Gaskets
- sealants
where are dynamic seals used?
where there are moving parts?
what are 4 basic types of radial lip seals?
- Single lip seals
- Single lip spring loaded
- Double lip
- Dual lip
single lip seals have?
One sealing lip that is not spring loaded
Single lip spring loaded seals have?
One sealing lip that is spring loaded
double lip seals have?
One spring loaded lip, and one dust lip
Dual lip seals have?
Two lips and both are spring loaded
what are the common designs of mechanical seals?
- Exclusion
- Clearance
- Wind Backs
- Face seals
- Dust shields
what are some of the common types of bearing failure?
- Peeling
- Spalling
- Brinelling
- Arcing
- Fatigue
What is peeling caused by?
an insufficient lubricating film
Heavy preload and poor lubricant film may result in?
Spalling
