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 Lubrication (continued) __________________________________________________________________
LUBRICANT SHELF LIFE
Lubricants will lose their effectiveness over time, therefore all lubricants will have a finite shelf life, and this information, together with date of manufacture, must be controlled in order to assure expected lubricant performance. All Dynaroll bearings are supplied containing lubricants that are within shelf life.
SPEED LIMITATION (LUBRICANT FACTOR)


For bearings with low-viscosity petroleum oil lubricant, the maximum operating speed is dictated by cage type and material, and centrifugal ball loads. In this ideal case the maximum operating inner ring rotation speed is given from the speed factor dN, where dN is the product of the bearing bore (d mm) times the maximum speed (N RPM). Depending on bearing design, dN can have values up to 600,000.

The maximum inner ring rotation speed with petroleum oil lubricant, Nmax RPM, is given for each bearing size in the individual bearing tables of this catalog. This value must be reduced by a lubricant factor fn to obtain the actual maximum inner ring operating speed of a bearing with a particular grease lubricant.

Nactual = Nmax • fn           (See bearing tables for individual Nmax values)

Values of the lubricant factor fn are given in the grease lubricant charts on the next page.

In the case of outer ring rotation, maximum speeds are reduced by approximately 20%. For more specific information on maximum bearing speeds in different applications, contact Dynaroll.
LUBRICANT CHARTS

OIL LUBRICANTS
DYNAROLL LUBRICANT CODE
MANUFACTURER TRADE NAME
BASIC TYPE
WORKING TEMP
VISCOSITY Cs
CHARACTERISTICS
AF2
SHELL OIL AEROSHELL 12
Diester
-65 to 250 oF
(-54 to 121 oC)
89 @ 130 oF
Light general purpose oil (MIL-L-6085C)
WL2
Fuchs Lubricant Co. Windsor Lube L-245X
Diester
-65 to 250 oF
(-54 to 121 oC)
31 @ 100 oF
Light general purpose oil (MIL-L-6085C)
SW16
NSK
SW16 Plating Oil
Ester
-40 to 265 oF
(-40 to 130 oC)
90 @ 100 oF
Low SVP*, low torque, grease replacement
KC1
Dupont Krytox 143AC
Fluorocarbon
-30 to 550 oF
(-34 to 288 oC)

270 @ 100 oF
High temperature, very low SVP*
* SVP = Saturated Vapor Pressure      

Note: Where grease is not suitable for a given application (e.g. for low torque), then a MIL-L-6085C oil lubricant is an industry standard. (If no lubricant specification is given by the user then Dynaroll bearings are normally supplied with AF2 lubricant, above.) Other oil lubricants are only to be used in specialized applications and may have limited availability or be expensive. Contact Dynaroll for more information on available oil lubricants.