Cookies on the SKF website

We use cookies to ensure that we give you the best experience on our websites and web applications. By continuing without changing your browser settings, we assume you give your consent to receive cookies. However, you can change your browser cookie setting at any time.

Standard bearing unit design

SKF inch roller bearing units consist of a non-split housing, an SKF spherical roller bearing in the 222 series, seals and grease. The bearings are fixed to the shaft using either the locking collar method or the SKF ConCentra locking method (designation suffix N). Inch roller bearing units are available in different series and designs:

  • Pillow (plummer) block units with two bolt holes in the base are available in two series. Units in the SYE and SYE .. N series are available for shafts ranging from 1 7/16 to 3 1/2 inches (fig. 1). Bearing units in the SYR and SYR .. N series are available for shafts ranging from 1 7/16 to 4 inches (fig. 2).
  • Four-bolt base pillow (plummer) block units in the SYE series, designation FSYE and FSYE .. N, are available for shafts ranging from 2 7/16 to 4 15/16 inches (fig. 3).
  • Square flange units (FYE series) are available for shafts ranging from 1 7/16 to 4 inches (fig. 4).
  • Round flange units (FYR series) are available for shafts ranging from 1 7/16 to 4 inches (fig. 5).
  • Piloted flange units (FYRP series) are available for shafts ranging from 1 7/16 to 4 inches (fig. 6).

SKF ConCentra locking method

The SKF ConCentra locking concept is based on two sets of inclined planes (serrations): one set in the bearing bore, the other on the stepped sleeve. When the set (grub) screws in the mounting collar are tightened, the bearing is displaced axially, forcing the inner ring to expand. This does two things: it sets the correct internal clearance within the bearing and it exerts pressure on the stepped sleeve, forcing it to contract around the circumference of the shaft for a true concentric, tight fit (fig. 7). On the opposite side are set (grub) screws for dismounting. An engraving marked “MOUNT.SIDE/DISMOUNT.SIDE” shows the mounting and dismounting sides of the unit.

Locking collar method

The locking collar method uses a collar mounted on the extended inner ring of the bearing (fig. 8). The extended inner ring has two holes, 62° apart. The collar has two matching tapped holes, each containing a set (grub) screw. When the set (grub) screws are fully tightened, the shaft is held firmly against the inner ring of the bearing.
SKF logo