Page 173 - Y-bearing-units

Pressed steel housings have a lower load car- Fig. 13
rying capacity than their insert bearings. Per-
missible radial loads are specified in the product
tables. The axial load should not exceed 20% of
the permissible radial load.
If the Y-bearing units will be subjected to
shock loads or variable axial loads, a grey cast
iron or Y-TECH housing should always be used.
Flanged composite housings and most grey
cast iron housings have a recess († fig. 13a), H11
or shoulder († fig. 13b) at the back for accu- D a
rate positioning, either on an appropriate shoul-
der or in a bore in the machine wall.
An appropriate shoulder can be provided by
one of the following methods:

• machining the wall accordingly († fig. 13c)
• attaching an appropriate washer to the wall a
by several screws († fig. 13d)

Furthermore, these features relieve the 4
attachment bolts of radial forces.

Attaching to a support surface
Flanged Y-bearing units have two, three or four
bolt holes through which they can be attached to
their support surface with threaded fasteners. D a h8
These bolt holes are:

• round and reinforced with pressed steel
inserts in composite housings
• drilled and round in cast housings
• square in pressed steel housings

In the absence of a centring shoulder and when b
heavy loads apply, SKF recommends doweling
the housing to its support surface. Dimples for
the dowel pin holes are cast into housings in the
FY, FYJ, FYTB and FYTJ series. Information on
the position and size of the holes for these dowel
pins is provided in table 1, page 172.

c d

171