What does a bearing do ?
Constrains relative motion to Desired motion and reduces friction between moving parts.
What does the design of a bearing provide ?
Provides linear movement / rotation around fixed axis
What is the role of gears ?
Transmits power, change drive directions and increases / decreases rotational speed.
What’s the two major groups of bearings ?
- Plain - made up of a plain cylinder or flat washer
2.Rolling - Made up of rolling components
What two good characteristics does bearings have ?
- Made from strong material
- Provides Quiet and efficient operation
What’s the two forces acting upon a bearing ?
- Axial
- Radial
( bearing can have combo of both )
What distributes lubricant over all of the bearing ?
Oil grooves/wells
What are synthetic bearings lubricated with ?
Water, whicch also acts as coolant
With sliding bearings, why is grease lube used ?
Used on stressed bearings to with large bearing play.
What loads does plain bearings take ?
Radial ( journal )
When are plain bearings used ?
When load is light a motion is continuous.
What’s pivot ( axial ) bearings used for ?
Longitudinal forces
What’s 3 advantages of roller and ball bearings ?
- Almost eliminate all friction
- Carry heavy loads
- Don’t heat as much as plain bearings
What the 5 types of anti-friction bearings ?
- Tapered
- Ball
- Needle
- Cylindrical
- Spherical
What separates the different raceways ?
Cage
What’s the raceways made from on anti-friction bearing ?
- Chromium steel
- Chromium - nickel steel
( tracks are polished )
What is the distinction between ball bearings and roller bearings ?
Ball bearings - low starting resistants, and high rotational speed.
Roller bearings - are used if stress is too much for ball bearings
What are the major components of ball bearing ?
- Outer ring
- Inner ring
- Rolling elements
- Retrainer
What’s the shields and sealants inside the races used for ?
To retain lubricant and protect bearing from contamination.
( races can be machined externally or internally to make them self angling )
What are ball bearings used for ?
Accessory drives, gearings
( anywhere narrow bearing is required )
What load is ball bearings poor at withstanding due to their point contact
Oscillating loads.
When is cylindrical bearings commonly used ?
Non-locating positions
What two types of bearings are placed at the end of shaft ?
- Locating (fixed)
- Non-locating (floats)
What does the cylindrical bearings line contact with races allow it to do over ball bearings ?
Carry more radial loads.
