6209-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 6209-NSK model number is decoded

6209 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the light 62xx section (diameter series 2 of ISO 15), multiplying bore code 09 by five gives the 45 mm bore; the 85 mm outside diameter and 19 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. 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

• A 45 mm shaft for 6209 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.
• At 45 mm bore the 62xx light series is the workhorse section; its 85×19 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: 6209-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 6209 units.
• Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6200-series position can soften the mixture and leak — clean out the old fill before switching grease types.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 19 mm-wide ring of 6209-NSK drags the lip and overheats it.
• The open 6209 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.
• The 45 mm bore puts 6209 in NSK's general-purpose industrial range; the standard pressed-steel cage and CN clearance cover most electric-motor and pump duty. NSK's VV non-contact seal is the high-speed choice here — DDU contact seal costs roughly 30–40% of the open-bearing speed ceiling.
• At 34.5 kN dynamic load rating (C) and 20.4 kN static (C0), 6209 is a medium-load NSK bearing suitable for most electric-motor and pump duty; the C0/C0r ratio matters for preloaded or thrust-loaded arrangements, so confirm the static safety factor with the NSK catalogue.
• At 420 g, 6209 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 45×85×19 mm envelope of 6209 gives a D/d ratio of 1.89 and 20.0 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 34.5/20.4 kN load ratings, mass 420 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6209 on the 45×85×19 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6209 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's VV non-contact seal keeps frictional torque close to the open 6209; in motor duty where heat build-up matters, VV is the usual compromise between debris protection and speed capability.
• When replacing a failed unit, inspect the shaft and housing seats before fitting the new 6209 — a new bearing pressed onto a worn or oval seat reproduces the original failure mode in a fraction of its expected life.