Page 677 - SKF-bearing-housings

Design considerations

Additional housing support for bearing units in life for the relubrication-free variant on
the SYNT series page 680.
When the housing is subjected to loads acting The housing material does not have any
parallel to the support surface, it may be additional temperature limits, except for very
ne cessary to pin the housing to the support low temperature applications where impact
surface or to provide a stop to counter the strength could be a factor.
load. The housing paint is heat resistant up to
In cases where the resultant radial load is 80 °C (175 °F) material temperature or 100 °C
between 55° and 120° or when the axial load is (210 °F) ambient temperature.
greater than 5% of P 180° († table 3, page 671),
the bearing unit should be pinned to its sup-
port surface. The dowel pins should be suffi- Operating speed
ciently strong to accommodate the loads act- The speeds at which SKF ConCentra roller
ing parallel to the support surface. bearing units can be operated depend on the
Recommendations for the position and size sealing solution in the bearing unit. For bear-
of the holes to accommodate dowel pins are ing units fitted with double-lip or heavy-duty
provided in table 12 on page 683. radial shaft seals, the limiting speeds are
based on the permissible circumferential
speed at the seal lips. For those fitted with
Radial internal clearance labyrinth seals, the limiting speeds are
The upgraded SKF Explorer spherical roller imposed by the bearing size and the grease.
bearings in SKF ConCentra roller bearing units Guideline values for the limiting speeds are
are manufactured standard with C3 radial listed in the product tables.
internal clearance. The clearance values, in
accordance with ISO 5753-1, are provided in
table 6 and are valid for unmounted bearings Shaft specifications
under zero measuring load. SKF ConCentra roller bearing units can be used
with commercial grade shafts that meet the
h9V E tolerance class for dimensional accuracy
Operating temperature and an IT5/2 tolerance for cylindricity, in
The permissible operating temperature of SKF accordance with ISO 1101.
ConCentra roller bearing units is limited by the
lubricant († table 8, page 675). For relubri-
cation-free units, refer to the section Grease

Table 6
Radial internal clearance of bearings in SKF ConCentra
roller bearing unit.
Bore diameter Radial internal clearance
d
over incl. min. max.
mm µm

30 40 50 65
40 50 60 80
50 65 75 95
65 80 95 120
80 100 110 140
16

673