61818-2RS bearing: complete specifications & equivalents
The 61818-2RS is a ISO 15 radial bearing sized 90 x 115 x 13 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 90 mm |
| Outer diameter D | 115 mm |
| Width B | 13 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 19.5 kN |
| Basic static load rating C0 | 17 kN |
| Fatigue load limit Pu | 0.915 kN |
| Limiting speed (mechanical) | 3200 rpm |
| Operating temperature | -30 to +110 °C |
| Mass | 290 g |
| Manufacturer designation | SKF 61818-2RS1 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-24 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 61800-series range
| Bore d | 3.543 in |
|---|---|
| Outer diameter D | 4.528 in |
| Width B | 0.512 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 12.5 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 29 of 74 |
| Bore above smallest 61800-series size | 89 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61818-2RS-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61818-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61818-RSR-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61818-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
| 61818-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61818-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61818-RSR-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61818-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×115×13 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 61818-2RS model number is decoded
In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61818 carries bore code 18 = 90 mm. Outside diameter 115 mm and width 13 mm come from the ISO 15 boundary-dimensions general plan. Suffix -2RS denotes two contact-type elastomer seals over a lifetime grease fill; the sealing lips add drag compared with open or shielded versions. For normal-load mounting with a rotating inner ring on a 90 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. SKF's contact-seal catalogue number is 61818-2RS1 (older text: -2RS1), mapped here from the industry-neutral -2RS spelling.
Typical equipment & failure modes
Common applications
- lay shafts and idler shafts
- textile machinery
- packaging machinery
- space-constrained gearboxes
Known failure patterns
- seal-lip hardening and loss of pre-grease in sustained high-temperature service
- grease-life expiry in the sealed-for-life cavity (no relubrication path)
- cage damage from operation beyond the limiting speed
- electrical pitting in VFD-driven motors without grounding protection
Selection pitfalls — read before you substitute
- At 90 mm bore the ring mass is significant: heat 61818 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
- The 618xx thin section at 90 mm bore has only a 12.5 mm radial section height: it saves space but is highly sensitive to misalignment, shaft deflection and shock loads — verify shaft stiffness before choosing it over a 6218.
- Contact seals add drag and heat: 61818-2RS runs slower and cooler-limited than the open 61818; rubber lips are generally limited to roughly 80–110 °C continuous depending on grease, and C3 clearance is the common hot-duty choice.
- Heat is the enemy of the sealed 61818-2RS: sustained running near the lip temperature limit hardens the rubber, after which grease escapes and dirt tracks in — watch the housing temperature in hot drives.
- The housing bore for the 115 mm OD should be round within IT7; an oval bore pinches the outer ring of 61818-2RS and shows up later as two-point loaded raceway wear.
- Shaft and housing fillets must clear the bearing chamfer so the 13 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
- SKF catalogues the contact-sealed version as 61818-2RS1 (older printings may read -2RS1); it is shipped pre-greased and its 3200 r/min limiting speed is set by seal-lip drag and grease life versus the open bearing's 11000 r/min thermal reference speed.
- The 19.5/17 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 61818-2RS bearing?
A 61818-2RS deep-groove ball bearing has a 90 mm bore, 115 mm outer diameter and 13 mm width (3.543 × 4.528 × 0.512 in), per ISO 15 boundary dimensions. It is fitted with two contact rubber seals and is normally pre-greased.
What lubrication does 61818-2RS need?
61818-2RS is supplied pre-greased for life and is not designed to be opened for relubrication; where a relubrication path is required, specify the open 61818 with a housing grease fitting instead.
How does the 61818 bore code work?
The last two digits of 61818 are bore code 18, giving 18 × 5 = 90 mm bore. The 115 mm outside diameter and 13 mm width follow the ISO 15 diameter series, not the bore code alone.
What does the 2RS suffix on 61818-2RS mean?
2RS means two contact elastomer seals, one each side, usually over a lifetime grease fill. Sealing against dust and moisture is better than ZZ shields, but the lip drag lowers the speed and temperature ceiling.
What is the SKF designation and catalogue data for 61818-2RS?
In the SKF Rolling Bearings catalogue this size is listed as 61818-2RS1 — two contact elastomer seals over a lifetime grease fill, 90×115×13 mm per ISO 15. Quoted values: C 19.5 kN, C0 17 kN, Pu 0.915 kN, limiting speed 3200 r/min, mass 290 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61818-2RS.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.