Page 45 - Y-bearing-units

Attaching to the support Fig. 6
surface
1
T o attach Y-bearing units to the support surface,
SKF recommends using 8.8 class bolts or studs
and a washer to ISO 7089:2000 or 7090:2000
and a spring washer. Hexagonal head bolts in
accordance with ISO 4014:1999 are appropriate. h 6 h 7
Alternatively, hexagonal socket head cap screws h 8 h 9 h 10 h 11
in accordance with ISO 4762:1988 can be used.
Appropriate fastener sizes are listed in the
product tables.

Shaft tolerances

Recommended fits for Y-bearings are listed in
table 2.
For moderate loads (0,035 C < P ≤ 0,05 C) the Table 2
shaft seats for Y-bearings with grub screws or Recommended fits
an eccentric locking collar should be machined Operating conditions Tolerance
to an h7 tolerance. For light loads and low
speeds, an h8 shaft tolerance is sufficient and, Y-bearings with grub screws
for very simple applications, h9 to h11 shaft or an eccentric locking collar
tolerances may be used. Fig. 6 illustrates the P > 0,05 C and/or high speeds h6
location of the most commonly used ISO shaft 0,035 C < P ≤ 0,05 C h7
tolerance grades for Y-bearings with grub 0,02 C < P ≤ 0,035 C and/or low speeds h8
screws or an eccentric locking collar. The values
of these ISO tolerances are listed in table 3a, Simple bearing arrangements h9 – h11
or P ≤ 0,02 C
page 44.
Y-bearings with a tapered bore on
an adapter sleeve or Y-bearings with
SKF ConCentra locking
All loads and speeds h9/IT5
Y-bearings with a standard inner ring
P > 0,035 C
Shaft diameter ≤ 17 mm j5
Shaft diameter ≥ 20 mm k5
P ≤ 0,035 C
Shaft diameter ≥ 20 mm j6

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