Transcript Rollin’ Rollin’ Rollin’

Rollin’ Rollin’ Rollin’
By Nathan Powell
And
Jonathan Parkinson
Classifications
• Radial
• Thrust
• Tapered
Radial
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Support only radial loads
Thrust
• Supports only axial loads
Tapered
• Able to carry combinations of thrust and radial
loads
Why Rollers?
• Support larger static and dynamic loads than
ball bearings
• Less expensive for larger sizes and heavier
loads than ball bearings.
Roller Vs. Sliding
Advantages of Roller Bearings
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Low starting and operating friction
Can support combined radial and thrust loads
Less sensitive to interruptions of lubrication
No self-excited instabilities
Good low-temperature starting
Can seal lubricant within bearing and “lifetime-lubricate”
Typically require less space in axial direction
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Machine Design by Norton (676)
Roller Vs. Sliding
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Disadvantages of Roller Bearings
May eventually fail from fatigue
Require more space in radial direction
Poor damping ability
Higher noise level
More severe alignment requirements
Higher cost
Higher friction (than hydrodynamic sliding)
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Machine Design by Norton (676)
Rolling Bearings
Rolling Bearings
Roller Bearings
Ball Bearings
Radial Roller Bearings
Thrust Roller Bearings
Single row Cylindrical
Double Row Cylindrical
Cylindrical
Needle
Needle
Single Row Tapered
Tapered
Spherical
Double Row Tapered
Spherical
Vendors
• Micro Miniature Bearing Co., Inc.
– www.mmbbearings.com
• Del-Tron Precision Inc.
– www.deltron.com
• Berg, W. M., Inc
– www.wmberg.com
• Stock Drive Products/Sterling Instruments
– www.sdp-si.com
• The Torrington Co.
– www.torrington.com
• Messinger Bearings Corp.
– www.messingerbearings.com
• RBC Bearings
– www.rbcbearings.com
• *The Bearing Detective
– www.emersonbearing.com/prods.html#bd
• Nachi Tech
– http://www.thomasregister.com/olc/nachiamerica/cylind.htm
Torrington manufactured its first bearing over 80 years ago. Significant product
innovation dates from the early 1930's, when our engineers developed the drawn
cup needle roller bearing, the outer ring of which is press-formed from strip steel
rather than machined. Other technical breakthroughs have included: the needle
roller thrust bearing, drawn cup roller clutch, wide inner ring bearing with eccentric
locking collar, aircraft control bearings, the screwdown roller thrust bearing for
metal rolling mills, and the innovative, assembled camshaft. Many specialized
products have also been designed for specific applications.