61811-2RS bearing: complete specifications & equivalents

Specification table

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.

Cross references & equivalents

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 61811-2RS model number is decoded

In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61811 carries bore code 11 = 55 mm. Outside diameter 72 mm and width 9 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 55 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 61811-2RS1 (older text: -2RS1), mapped here from the industry-neutral -2RS spelling.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 55 mm bore, induction heating to roughly 80–100 °C is the clean mounting method; never exceed 120 °C, and hold 61811 against the shaft shoulder while it cools so the ring cannot creep back.
• The 618xx thin section at 55 mm bore has only a 8.5 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 6211.
• Contact seals add drag and heat: 61811-2RS runs slower and cooler-limited than the open 61811; 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 61811-2RS: 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.
• Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
• Measure the shaft, do not trust the drawing: a 55 mm nominal journal worn by even 0.02 mm turns an interference seat into a creeping fit that frets the bore of 61811-2RS.
• SKF catalogues the contact-sealed version as 61811-2RS1 (older printings may read -2RS1); it is shipped pre-greased and its 5300 r/min limiting speed is set by seal-lip drag and grease life versus the open bearing's 19000 r/min thermal reference speed.
• The 9.04/8.8 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.