Page 1010 - Rollingbearings

18 High temperature bearings
Deep groove ball Designs and variants Integrated shields
High temperature deep groove ball bearings
bearings for high The SKF assortment of deep groove ball with designation sufix 2Z have integrated
bearings for high temperature applications shields, but the VA201 variant is also available
temperature (ig. 6) provides solutions for various combi- as an open bearing (ig. 6)
nations of operating temperature and speed.
applications The lubrication type, maximum operating External shields
temperature, limiting speed, maintenance
SKF deep groove ball bearings for high tem- requirements and all other primary charac- In some cases, integrated shields are insufi-
perature applications correspond in design teristics of the variants within the assortment cient and additional external shields should
to standard single row deep groove ball are listed in table 1. be considered, such as:
bearings of the same size They have no illing
slots and can accommodate axial loads in • Nilos rings (ig. 7)
addition to radial loads (Loads and selecting Sealing solutions • SKF sealing washers (ig. 8)
bearing size, page 1012)
The entire surface of the bearing and High temperature deep groove ball bearings For additional information about sealing
shields are manganese phosphate coated to can be protected from contamination by solutions, refer to External sealing,
enhance adhesion of the lubricant to the metal either integrated shields, external shields or page 194, and Seals (skf com/seals)
and improve the running-in properties of a combination of both.
the bearing For high temperature bearings, metallic NOTE: Because of the large radial clearance
18 The radial internal clearance is a multiple shields are the primary recommendation for high temperature deep groove ball bear-
of C5 to prevent the bearings from seizing, where a capping device with low complexity ings, special attention should be given to the
even when they cool rapidly. is required. The shields: design of the sealing arrangement

• prevent the ingress of solid contaminants Custom-made seals
into the bearing
• are non-contacting In cases where neither integrated nor external
• generate no friction shields are applicable, SKF can provide
• do not wear custom-made seals for operating tempera-
• are particularly well suited for high tem- tures up to 250 °C (480 °F) These seals are
peratures because of their material and usually made of PTFE (polytetraluoroethyl-
design ene) thermoplastics
To further improve sealing systems that
incorporate custom-made seals, it is prefer-
able to use a wear sleeve such as the
SKF Speedi-Sleeve (skf com/seals) This
improves the seal counterface condition
without the need for re-machining For
additional information, contact SKF

Fig. 5
Customized deep groove ball bearings

 WARNING
PTFE seals exposed to an open lame or
temperatures above 300 °C (570 °F) are
a health and environmental hazard!
They remain dangerous even after they
have cooled
Read and follow the safety precautions
on page 197

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