Grease for Pillow Block Bearings

Pillow block bearings (also called plummer blocks) are self-contained bearing units commonly used to support rotating shafts in industrial equipment. They typically include a housing, bearing, seals, and provisions for relubrication.

Factory Fill vs. Service Grease

Most pillow block bearings ship with factory-applied grease. When relubrication is required, verify compatibility between the factory fill and service grease, or purge the old grease completely before applying new lubricant.

Relubrication Intervals

Relubrication frequency depends on operating speed, temperature, and contamination level. Many manufacturers provide relubrication calculators or charts specific to their bearing designs.

Relubrication Procedure

Apply grease slowly through the fitting while the shaft is rotating if possible. This helps distribute grease evenly around the bearing. Avoid over-greasing, which can cause overheating and seal damage.

Seal Considerations

Pillow block bearing seals help retain grease and exclude contaminants. Heavy-duty seals are available for harsh environments but may require more frequent relubrication due to higher friction.

Environmental Factors

Select grease properties based on the specific environment:

• Wet conditions: Calcium sulfonate or aluminum complex thickeners provide better water resistance
• Dusty conditions: Ensure proper seal function; consider more frequent relubrication
• High temperatures: Use synthetic base oils with appropriate thickener dropping point