Plummer Blocks

General Features

The following is an extract from the SKF catalogue, edited for this Handbook.

Bearing housings fitted with rolling bearings are economic, replaceable bearing units and require little maintenance.

SKF bearing housings are generally made of cast iron and the bearing seating of the housings is machined to tolerances such that a loose fit of the bearing outer ring is ensured.

For further details on seals, page down or click here.

SKF bearing housings are primarily intended for grease lubrication. In the majority of cases it is sufficient to charge the housings with grease on mounting and to replace this grease periodically when carrying out inspections.

Plummer block housings usually have no provision for re-lubrication since used grease can be easily replaced once the housing cap has been removed.

If shorter re-lubrication intervals are required a hole may be drilled and tapped to take a grease nipple or supply line. Plummer blocks are designed for use with self-aligning ball bearings and spherical roller bearings where the bearing either has a tapered bore and be mounted on an adapter sleeve, or the bearing has a cylindrical bore. Elongated bolt holes are provided in the plummer block housing base to permit slight adjustments to be made to the position of the plummer block during mounting.

Most housings are fitted with dowel pins to ensure correct location of the associated caps and bases, which are not interchangeable.

Plummer blocks are designed to accommodate loads acting at right angles to the base. If the direction of load is not perpendicular to the base, care should be taken to see that the housing, cap bolts and holding down bolts have sufficient strength to carry the loads involved.

For further details regarding loading of plummer blocks, click here.