6211-RSR-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 6211-RSR-NTN model number is decoded

6211-RSR uses two non-contact elastomer lips with very low drag; coarse debris stays out, but the bearing is not liquid-tight. Within the light 62xx section (diameter series 2 of ISO 15), multiplying bore code 11 by five gives the 55 mm bore; the 100 mm outside diameter and 21 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 55 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 non-contact seal suffix is LLB/LLF (catalogue number 6211LLB), mapped here from the industry-neutral -RSR spelling; speed capability matches the open bearing but it is not liquid-tight.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Temperature rise and interference fits consume internal clearance on this 55 mm bore: a CN bearing on a tight, hot shaft can lose all residual clearance — size 6211 with C3 for those conditions.
• At 55 mm bore the 62xx light series is the workhorse section; its 100×21 mm envelope is what most motor and gearbox seats are machined for, so any alternative section must be checked against both this OD and this width, not the bore alone.
• RSR low-friction seals on 6211-RSR-NTN run faster than contact-seal 6211-2RS but let fine dust and moisture past the non-contact lip; in dirty or wet duty specify 6211-2RS instead.
• The non-contact lip of 6211-RSR-NTN does not retain a lifetime grease fill the way a contact seal does; confirm the regreasing interval for the 55 mm bore position before relying on it as sealed-for-life.
• Do not quieten a noisy bearing by preloading it: the 6200-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
• 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.
• NTN catalogues this low-friction non-contact seal as 6211LLB (suffix LLB), mapped here from the industry-neutral -RSR spelling. NTN rates its speed capability the same as the open bearing, but it is not liquid-tight — for wet or fine-dust duty step up to the LLU contact seal (industry-neutral -2RS).
• At 55 mm bore 6211 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-section 63xx sizes at this bore can be ordered with a machined brass cage (suffix M) for heavy-shock or very-low-speed duty — confirm cage material with the NTN channel if the application sees impact loads.
• At 6400 r/min the grease limiting speed for 6211 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
• NTN rates 6211 at 48 kN dynamic (C) and 29.2 kN static (C0), 2.29 kN fatigue load limit Cu; this upper-medium rating covers conveyor and gearbox drives, but at these loads the pressed-steel cage can be the limiting factor under shock — consider the machined brass cage (suffix M) for impact duty.
• At 601 g, 6211 requires a soft-jaw vise or arbor press for mounting — never hammer it onto the shaft, and support the opposite ring to avoid brinelling the raceways.
• The 55×100×21 mm envelope of 6211 gives a D/d ratio of 1.82 and 22.5 mm radial section height — a standard medium section that balances load capacity and speed; for this geometry the pressed-steel cage is adequate up to the listed limiting speed, and C3 clearance is the common choice for hot shafts.
• The 48/29.2 kN load ratings, 2.29 kN fatigue load limit Cu NTN lists the grease limiting speed at 6400 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 601 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6211LLB on the 55×100×21 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6211 in a rated drive.
• Factory-fill grease in NTN sealed units is a general-duty lithium-soap grease; food-grade, low-temperature and high-temperature fills are request options at order time, because LLU/LLB units are not meant to be opened and re-greased in the field.
• Order the C3 internal-clearance version (6211 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.