6211-NSK bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24

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-NSK model number is decoded

In the 6200-series (diameter series 2 of ISO 15) the last two digits encode the bore: 6211 carries bore code 11 = 55 mm. Outside diameter 100 mm and width 21 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. 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. In the NSK catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals).

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.
• Storage matters for open bearings: 6211-NSK leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
• Open bearings tolerate the highest speeds in the 6200-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6211 units.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 21 mm-wide ring of 6211-NSK drags the lip and overheats it.
• Vibration during standstill brinells the raceways of a 55 mm bearing at ball spacing; if the machine sits idle next to running equipment, turn the shaft over periodically or isolate the arrangement.
• The open 6211 has no integral sealing; in the NSK E1103 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals). NSK does not offer a low-torque contact seal equivalent to NTN's LLH in this catalogue — for high-speed sealed duty specify the VV non-contact seal and an external housing labyrinth.
• At 55 mm bore 6211 is in NSK'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 NSK channel if the application sees impact loads.
• NSK rates 6211 at 47.5 kN dynamic (C) and 29.3 kN static (C0); 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 619 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 NSK medium section that balances load capacity and speed; for this geometry the pressed-steel cage is adequate up to NSK's listed speed ratings, and C3 clearance is the common choice for hot shafts.
• The 47.5/29.3 kN load ratings, mass 619 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6211 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. NSK does not tabulate reference or limiting speeds in the E1103 Part C dimension tables used for this page — consult NSK's separate speed-rating tables before high-speed service.
• NSK does not recommend washing new shielded or sealed bearings; the rust-preventive film on open units is compatible with standard lithium greases and needs no removal unless the application demands a special fill.
• NSK supplies its sealed units pre-greased for general duty between roughly -10 and +110 °C; low-temperature, food-grade and high-temperature fills are special executions — ask at order time, because DDU/VV units are not designed to be opened and repacked.