01 - Bearings / Bushings * Flashcards
What are deep groove ball bearings typically used for
thanks to their simple design, they are easy to maintain and are not as sensitive to operating conditions as other bearings are. Their low torque makes them suitable for high speeds. They are often seen in motors, and a wide variety of other applications. They have a deep groove with lightly separated ball bearings.
What are thrust ball bearings typically used for?
Thrust bearings are made of two bearings discs with raceways for the balls. They are designed solely to absorb axial forces in one direction.
What are roller bearings typically used for?
Roller bearings are used for slower rotation, but higher load rating.
What are sleeve bearings (bushings) used for?
Bushings are used for light axial loads with fast rotation, in environments that call for quiet operation.
What temperature should bearings be heated to before being installed on the shaft?
230F
What is the maximum safe operating temperature for bearings?
180F
What method is used to check motor shaft alignment?
Dial indicator method
What method is used to check shaft runout?
Runout gauge
Recite the steps for a bearing/bushing replacement
- Ensure you have the proper part needed for replacement
- Inspect the shaft for wear, damage, and straightness
- Verify the shaft and bearing surfaces are clean and free of oil, rust, or contaminants
- Pre-lubricate as appropriate
- Using proper tools, install bearings (heating, cooling, pressing)
- Establish proper clearances
- Inspect oil/grease lines
- Verify proper alignment and tolerance
- Replace fasteners as needed
- Check operation of newly installed bearings.
What should be examined during a routine bearing/bushing examination?
- Check for any damage to the bearings, cleanliness, and cracks.
- Check for excessive vibration, or play in the bearings.
- Check setscrews for proper tightness
- Check alignment
- Check for lubrication and operating temperature
Where are seals present on bearings, (if present) and what are their purpose?
They are present on the outer rim of the bearing, they prevent excess grease from getting out of the bearing and contaminants from getting in.
How would a crack develop, and where would it be located?
It could be caused due to misalignment, runout, or overheating. Could be located anywhere on the bearing
What is the maximum tolerance allowed between the bearing and the shaft?
.001”
What method is used to check proper alignment of sheaves and pulleys?
The straight edge or string method can be used. 4 points of contact along the string must be achieved to verify proper alignment.
What is the measurement classification for a bushing?
the letter will represent a type or classification of bushing, followed by a measurement for the bore size. (ex: Q1 11/16, or Q1 24mm)
