Page 610 - Rollingbearings

7 Needle roller bearings
Temperature Seals Permissible speed
The permissible operating temperature for
limits seals depends on the seal material:
The speed ratings in the product tables
• NBR: –40 to +100 °C (–40 to +210 °F) indicate:
The permissible operating temperature for Temperatures up to 120 °C (250 °F) can
needle roller bearings can be limited by: be tolerated for brief periods • the reference speed, which enables a
• PUR: –30 to +100 °C (–20 to +210 °F) quick assessment of the speed capabilities
• the dimensional stability of the bearing • FKM: –30 to +200 °C (–20 to +390 °F) from a thermal frame of reference
rings and rolling elements Temperatures up to 230 °C (445 °F) can • the limiting speed, which is a mechanical
• the cages be tolerated for brief periods. limit that should not be exceeded unless
• the seals the bearing design and the application are
• the seating rings Typically, temperature peaks are at the seal adapted for higher speeds
• the lubricant lip.
For additional information, refer to Operating
Where temperatures outside the permissible Seating rings temperature and speed, page 129
range are expected, contact SKF
The permissible operating temperature for
Bearing rings and rolling seating rings is –30 to +100 °C (–20 to
elements +210 °F)

SKF needle roller bearings, and roller and Lubricants
cage assemblies are heat stabilized up to
120 °C (250 °F) Temperature limits for greases used in
Drawn cup needle roller bearings are heat capped needle roller bearings are provided
stabilized up to 140 °C (285 °F). in table 3, page 595, and for full comple-
ment drawn cup needle roller bearings in
Cages table 1, page 585 For temperature limits of
7 other SKF greases, refer to Selecting a suita-
Steel cages can be used at the same operat- ble SKF grease, page 116
ing temperatures as the bearing rings and When using lubricants not supplied by
rolling elements. For temperature limits of SKF, temperature limits should be evaluated
polymer cages, refer to Polymer cages, according to the SKF trafic light concept
page 188. (page 117)

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