Timken - Ball Bearing Housed Units

BALL BEARING HOUSED UNITS
ENGINEERING • LUBRICATION
VISCOSITY INDEX
The ideal oil (as far as viscosity is concerned) would be the same
viscosity at all temperatures. All oils become less viscous (thin-out)
when heated and more viscous (thickened) when cooled.
However, oils do not vary in viscosity to the same extent. Some
thicken or thin more rapidly than others.
The term viscosity index, or VI, is used to rate oils according to
their temperature-viscosity behavior.
Oils with the highest viscosity index are more resistant to changes
in viscosity with changes in temperature than lower viscosity index
oils. Obviously, high viscosity-index lubricants are most suitable for
bearing applications experiencing wide temperature variations.
The National Lubricating Grease Institute (NLGI) classification of
grease consistency is shown below (table A-5):
TABLE A-5. NLGI CLASSIFICATIONS
NLGI Grease Grades
Penetration No.
0 355-385
1 310-340
2 265-295
3 220-250
4 175-205
5 130-160
6 85-115
POUR POINT
The pour point is the lowest temperature at which a fluid will flow
or can be poured. It is important in applications exposed to low
temperatures that the lubricating fluid selected has a pour point
lower than the minimum ambient temperature.
WARNING
Failure to observe the following warnings
could create a risk of death or serious injury.
Proper maintenance and handling practices are critical.
Always follow installation instructions and
maintain proper lubrication.
TYPES OF LUBRICATION
Timken understands the importance of friction management.
Our line of application- and environment-specific lubricants has
been developed by leveraging our knowledge of tribology and
antifriction bearings, as well as how these two elements affect
overall system performance.
Timken ® lubricants help bearings and related components
operate effectively in demanding industrial operations. Hightemperature,
anti-wear and water-resistant additives offer
superior protection in challenging environments.
Similar to our bearings, all Timken lubricants are backed by highly
trained customer service and technical support associates.
Industrial customers turn to Timken for comprehensive friction
management solutions. We help customers analyze performance
and suggest options that make sense for their unique operating
conditions and maintenance intervals.
TABLE A-6. STANDARD BALL-BEARING LUBRICATION
Bearing Type
Radial bearings
(double shielded, and
single and double
shielded)
Wide-inner-ring
ball bearings
(contact seal types)
Wide-inner-ring
ball bearings
(labyrinth seal types)
Grease Type
Polyurea thickener
Petroleum oil
Polyurea thickener
Petroleum oil
Synthetic thickener
Synthetic hydrocarbon fluid
Grease
Temperature Range
-34.44° C to +135° C
(-40° to +275° F)
-34.44° C to +135° C
(-40° to +275° F)
-53.89° F to +162.75° C
(-65° F to +350° F)
NOTE: Open-type bearings and single-shielded types are not prelubricated. They
have a rust-preventative coating only and must be lubricated by the customer
or end-user before operation.
Bearings that have been factory pre-lubricated use a high-quality
grease. Bearings with contacting lip seals and shields contain
No. 2 polyurea base grease. Bearings with non-contacting
labyrinth seals (suffix KLL in bearing part number) contain a
No. 2 modified clay base grease. For normal conditions of service,
these bearings require no further lubrication.
Normal service is considered as operating in a clean, dry
environment at temperatures between -34° C to +82° C
(-30° F to +180° F ) and at dN values (bore in millimeter multiplied
by speed in RPM) less than 175000.
If service is considered abnormal due to speed, temperature
or exposure to moisture, dirt or corrosive chemicals, periodic
relubrication may be advisable. Excessive relubrication may
cause high operating temperatures due to grease churning.
General guidelines for relubrication are provided in table A-7.
TIMKEN ® HOUSED UNIT CATALOG • Download 3D Models and 2D Drawings at cad.timken.com A-9