Short answer: choose a solid oil bearing when relubrication is impractical, when grease purge or washout is unacceptable, or when the bearing must survive washdown and corrosive cleaning. Choose a grease-packed bearing when you need maximum speed or continuous operating temperatures above ~90 °C.
How each lubrication method works
A conventional bearing is packed with grease — a soap thickener carrying oil — and relies on periodic relubrication to replace oil that bleeds off, oxidizes, or escapes. A solid oil bearing instead has its internal free space filled with a polymer matrix saturated with oil. The matrix is solid: it stays put, holds several times more oil than a typical grease fill, and releases a thin lubricating film as the bearing rotates.
Side-by-side comparison
| Solid Oil Bearing | Grease-Packed Bearing | |
|---|---|---|
| Relubrication | Never — lubricated for life | Required at intervals |
| Washdown resistance | Cannot wash out | Grease can emulsify and wash out |
| Contamination of product | No purge, no drips | Grease purge possible |
| Mounting orientation | Any — fill cannot slump | Grease can slump in some orientations |
| Max speed | ~40–60% of open-bearing rating | Higher |
| Continuous temperature | Up to ~90 °C | Depends on grease; often higher |
| Maintenance cost | None | Labor + grease + missed-interval risk |
When solid oil is the right call
- Hard-to-access locations — rooftop fans, conveyors in ceilings, sealed gearcases, remote equipment.
- Food & beverage processing — with NSF H1 food-grade stainless versions, there is no grease to contaminate product and nothing for washdown to remove.
- Washdown and corrosive environments — chemical, pharmaceutical, and marine settings where grease washes out.
- Equipment where a missed lube interval means failure — the bearing simply has no lube interval.
When to stay with grease
- High-speed spindles or motors running near the bearing's rated speed limit.
- Continuous operating temperatures above roughly 90 °C.
Where to buy solid oil bearings
We stock over 205 sizes of solid oil impregnated deep groove ball bearings — metric 6000, 6200, 6300, thin-section 6800/6900, inch R series, 1600 series, and miniatures from 1 mm bore. Use the Bearing Finder to match your dimensions, or contact us for volume quotes.