A sealed (2RS) or shielded (ZZ) deep groove ball bearing can be replaced directly with a solid oil bearing of the same size: a 6203-2RS or 6203ZZ becomes a 6203-SL in Standard grade or S6203-FGSL in Food Grade. The dimensions, fits and mounting are the same. The bearing is sealed with solid oil, so it never needs regreasing.
What do 2RS and ZZ mean on a bearing number?
A deep groove ball bearing is the common single row ball bearing found in motors, conveyors, fans and pumps. The base number, such as 6203, gives the series and bore size, and the suffix describes how the bearing is closed.
2RS means two rubber seals, one on each face. They hold a factory grease charge inside the bearing and keep dust and moisture out.
ZZ, also written 2Z, means two metal shields. Shields keep debris out and grease in but do not seal against liquid.
Both types depend on the grease packed in at the factory, and neither can be relubricated in service.
Why do plants replace grease-packed sealed and shielded bearings?
Maintenance teams look for a sealed bearing replacement for a few recurring reasons:
- Grease ages, dries out or separates, and there is no way to add more to a sealed unit.
- Washdown and cleaning chemicals get past shields and lip seals and flush the grease out.
- Grease purges out of shielded bearings onto product, belts and floors, a contamination problem on food and packaging lines.
- Bearings mounted high in fans, inside motor enclosures or along long conveyors are hard to reach, so they run to failure.
A maintenance free bearing replacement takes the grease out of the equation.
What is a solid oil bearing?
A solid oil bearing is a standard deep groove ball bearing whose internal space is filled with Syn-Tech solid oil. Solid oil is a solid polymer lubricant that holds oil in a matrix and releases a thin film to the balls and raceways as the bearing turns.
The fill seals the bearing. There is no relubrication, no purge and no washout, and the bearing survives washdown and cleaning chemicals. Some call this a self lubricating bearing replacement. Read solid oil vs grease bearings for the comparison.
How do I match a 2RS or ZZ bearing to a solid oil bearing?
Match by the base number. The series and bore code stay the same, and the 2RS or ZZ suffix drops away because there is no seal or shield option.
- 6203-2RS or 6203ZZ becomes 6203-SL in Standard or S6203-FGSL in Food Grade.
- 6305-2RS or 6305ZZ becomes 6305-SL or S6305-FGSL.
- 608-2RS or 608ZZ becomes the 608 miniature solid oil bearing.
- R8-2RS or R8ZZ becomes the R8 solid oil bearing.
If the number is worn off, measure the bore (the shaft hole), outside diameter and width and enter them in the bearing finder. The store carries 204 sizes, from 1 mm bore miniatures to the inch R and 1600 series.
Then choose a grade. Standard has chrome steel rings and balls. Food Grade has stainless steel rings and balls with an NSF H1 registered solid lubricant, the registration category for lubricants that may have incidental contact with food. Every size comes in both grades. The food grade bearings guide covers the choice.
Why is there no sealed or shielded version of a solid oil bearing?
Because the solid oil fill seals the bearing. Once the lubricant cures, the internal space is filled, so no seal or shield option is offered and none is needed. You pick the size and the grade, and that is the whole part number.
How do I install a solid oil bearing in place of a 2RS or ZZ bearing?
Installation follows the same practice as the bearing you are removing:
- Use the same shaft and housing fits, since the dimensions are the same as the bearing it replaces.
- Mount it the same way, pressing on the ring that is being fitted, never through the balls.
- Keep the housing and shaft clean, and remove old grease and debris before the new bearing goes in.
- Do not add grease or oil. The bearing is already lubricated for service.
- If the housing has a grease fitting, cap it or remove it, and take the bearing off the relubrication schedule.
One design check: solid oil bearings run at lower maximum speeds than greased bearings, so email us about high-speed applications.
Where do solid oil bearings pay off the most?
The payoff is largest where relubrication is difficult, costly or a contamination risk:
- Food and beverage lines and other washdown equipment
- Conveyors and packaging machinery
- Marine and other wet environments
- Hard-to-reach motors, fans and pumps
- Textile and agricultural equipment
- Robotics and instruments in the small sizes
How do I order a replacement solid oil bearing?
Browse all sizes, a series collection such as the 6200 series or 6300 series, or the bearing finder, then pick Standard or Food Grade.
Every bearing is filled to order in our Glendale, California facility and ships in 7 to 10 business days by UPS or USPS within the United States. Standard shipping is a $10 flat rate and free on orders over $100. Express shipping with 3 to 5 day transit is $35.
Because bearings are filled to order, all sales are final. Wrong or defective items are replaced free if reported within 48 hours with photos, and an order can be canceled only before filling starts. There is no minimum order. For quantity quotes or help matching a part number, email info@solidoilbearings.com or use the contact form; we reply within one business day.
Frequently asked questions
Can I replace a 6203-2RS with a 6203-SL without changing anything else?
Yes. The 6203-SL has the same bore, outside diameter and width as a 6203-2RS or 6203ZZ, so the shaft, housing and mounting stay the same. The only change is that the bearing is sealed with solid oil and comes off the regreasing schedule.
Do I need to grease a solid oil bearing after installation?
No. The solid oil fill is the lubrication for the bearing, and it releases a thin film of oil to the balls and raceways as the bearing turns. Adding grease is not needed and should be avoided.
Can I get a solid oil bearing with seals or shields?
No. The solid oil fill seals the bearing, so there is no seal or shield option to select. Choose the size and the grade and the part number is complete.