FYH SA207-21 Spannlager (33,338x72x36,5)

As an insert (Y) bearing, this bearing is located on the shaft and used in a housing. The mounting dimensions are 33.338x72x36.5 mm and the weight is 0.5 kg; technical details beyond these are shown in the specification table. This version is meant for insert bearing locations at which the ingress is continuous rather than merely occasional.

The multiple seal places several sealing stages in series ahead of the rolling chamber. The benefit lies not in one stage sealing better than another but in the order: each upstream stage relieves the following one of part of its work, so that the innermost stage — the one whose failure acts directly on the rolling contact — stays effective longest.

In an insert bearing this meets an unfavourable mounting location: the design sits on exposed shafts, frequently in dusty, damp or fibrous surroundings, and the bearing position cannot be enclosed structurally. Where a single-stage seal wears out there as a matter of course, the staged arrangement extends the time until ingress into the rolling chamber and keeps the grease charge clean for longer.

The counterpart is a higher frictional torque and more heat, so the permissible speed lies lower than with a simpler seal; where a grease nipple is present, relubrication also supplies the sealing stages and belongs in the maintenance plan. The rest of the construction remains that of the insert bearing: a spherical outer surface for seating in a housing's spherical seat and for aligning during mounting, and a widened inner ring with grub screws, an eccentric locking collar or an adapter sleeve for the grip on the drawn shaft.

Rings and balls are made of standard bearing steel; a clearance class is not recorded as a separate catalogue attribute for these items. Where the installation space is tight, the overall width should be checked, since a staged seal takes up room at the end faces.