Page 216 - SKF-bearing-housings

Split plummer block housings SNL 30, 31 and 32 series

Operating temperature Lubrication
The permissible operating temperature
is mainly limited by the seals († table 1, SNL housings in the 30, 31 and 32 series with
page 197), and the lubricant in the bearing. labyrinth or taconite seals are intended for
For temperature limits of SKF bearings and grease lubrication. For oil lubrication, modi-
lubricants, refer to the product information fied housings with oil seals († page 198) or
available online at skf.com/bearings. SONL plummer block housings († page 349)
The housing material does not have any should be used.
additional temperature limits, except for very The lubricant should be selected based on
low temperature applications where impact the operating conditions of the bearing. For
strength could be a factor. additional information about lubricant selec-
The housing paint is heat resistant up to tion, refer to the product information available
80 °C (175 °F) material temperature or 100 °C online at skf.com /bearings.
(210 °F) ambient temperature.
When temperatures outside the permissible
range are expected, contact the SKF application Initial grease fill
engineering service. If no other requirements exist, the free space
in the bearing should be completely filled with
grease and the free space in the housing should
Operating speed be filled to 20 to 40% of its volume. A 40%
The permissible operating speed is not limited grease fill is required when bearings have to
by the housing, except when taconite seals be relubricated from the side, while a 20%
are used. The maximum speeds for taconite grease fill is used when bearings are relubri-
seals are provided in table 1 on page 197. cated via the outer ring.
For speed limits of the bearing, refer to the The housing base has markings to show the
product information available online at height of a 40% grease fill († fig. 11). For
skf.com/bearings. highly contaminated environments and slow
speeds, fill the housing to 70–80%. For best
protection against contaminants, use the SKF
Attachment bolt recommendations three-barrier solution († page 39). For add-
In typical applications, 8.8 class hexagon head itional information, contact the SKF applica-
bolts, in accordance with ISO 4014, can be tion engineering service.
used together with washers. If the load does Quantites for 20 and 40% grease fills are
not act perpendicularly toward the base, it listed in table 8 on page 213. The values are
may be necessary to use stronger 10.9 class valid for a typical lithium grease (about
bolts.
SKF housings can withstand loads resulting Fig. 11
from tightening the attachment bolts to the
torque values recommended by bolt manufac-
turers († table 7). They are valid for oiled,
but otherwise untreated, thread surfaces.
SKF cannot guarantee that tightening to the
recommended value will provide sufficient
anchoring. Make sure that attachment bolts,
dowels or stops, and a sufficiently strong sup-
port can accommodate all occurring loads.

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