61809-2RS-NTN bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.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 61809-2RS-NTN model number is decoded

61809-2RS is closed by two contacting elastomer lips over a lifetime grease fill; the lips add friction, so the speed ceiling sits below the open execution. Within the extra-thin 618xx section (diameter series 8 of ISO 15), multiplying bore code 09 by five gives the 45 mm bore; the 58 mm outside diameter and 7 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 45 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. NTN's contact-seal catalogue number is 6809JRLLU (suffix LLU, or LLH low-torque variant), mapped here from the industry-neutral -2RS spelling; the contacting lip lowers the speed ceiling versus the open bearing.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• A 45 mm shaft for 61809 should be finished to Ra ≤ 1.6 µm with square seating faces; at this bore a scored or oval journal shows up directly as running noise and early raceway damage.
• The 618xx thin section at 45 mm bore has only a 6.5 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 6209.
• Contact seals add drag and heat: 61809-2RS-NTN runs slower and cooler-limited than the open 61809; 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 61809-2RS: 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.
• Shaft and housing fillets must clear the bearing chamfer so the 7 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
• Deep-groove ball bearings tolerate only minutes of misalignment; if the 58 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 61809-2RS-NTN.
• NTN catalogues the contact-sealed version as 6809JRLLU (suffix RLLU), mapped here from the industry-neutral -2RS spelling; it is greased for life and the contacting lip lowers the speed ceiling versus the open bearing.
• The 45 mm bore puts 61809 in NTN's general-purpose industrial range; the standard pressed-steel cage and CN clearance cover most electric-motor and pump duty, but for continuous high-speed use specify the LLH low-torque seal (not LLU) and confirm the housing allows the listed limiting speed.
• At 5900 r/min the grease limiting speed for 61809 covers medium-duty industrial drives; the contact seal (LLU) is the main speed limiter here — for continuous operation above 80% of this figure use the open variant with an external labyrinth seal and oil bath.
• NTN rates 61809 at 5.95 kN dynamic (C) and 4.95 kN static (C0), 0.33 kN fatigue load limit Cu; this light-to-medium rating suits fractional-horsepower drives and instruments — for conveying or gearbox duty with shock loads, verify the equivalent dynamic load stays well below C.
• At only 40 g, 61809 is a lightweight bearing that can be handled by hand; still, press it onto the shaft with a sleeve against the inner ring — never through the balls or outer ring.
• The 45×58×7 mm envelope of 61809 gives a D/d ratio of 1.29 and only 6.5 mm radial section height — this is an ultra-thin section where shaft deflection and housing ovality directly load the ball-raceway contact; verify shaft stiffness (target deflection under 0.05 mm) before specifying it over a 62-series.
• The 5.95/4.95 kN load ratings, 0.33 kN fatigue load limit Cu NTN lists the grease limiting speed at 5900 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 40 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6809JRLLU on the 45×58×7 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61809 in a rated drive.
• NTN's pressed-steel cage (no cage suffix) is the quiet standard for this size; for sustained running close to the limiting speed or for heavy shock duty, ask the NTN channel whether a machined-cage execution of 61809 is listed.
• Standard catalogue stock of 61809 is the general-purpose execution; for low-noise motor duty NTN offers low-torque seal and special-grease variants in this size class, which are separate order numbers.