6205-2RS-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 6205-2RS-NSK model number is decoded

6205-2RS 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 light 62xx section (diameter series 2 of ISO 15), multiplying bore code 05 by five gives the 25 mm bore; the 52 mm outside diameter and 15 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 25 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. NSK's contact-seal catalogue number is 6205DDU (suffix DDU), 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.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• A 25 mm shaft for 6205 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 62xx light series is the default general-purpose section at 25 mm bore; before upgrading to a 6305 for extra capacity, confirm the housing accepts a 52 mm OD and 15 mm width — it is not a drop-in swap.
• Contact seals add drag and heat: 6205-2RS-NSK runs slower and cooler-limited than the open 6205; rubber lips are generally limited to roughly 80–110 °C continuous depending on grease, and C3 clearance is the common hot-duty choice.
• Never wash a sealed 6205-2RS-NSK in solvent or press it home via the outer ring; solvent destroys the grease thickener and mounting force through the seal deforms the lip.
• A 25 mm bore listing showing the right d/D/B but no standard or precision-class reference may be a loose-tolerance import; measure bore/OD spread before fitting it to a machined shaft.
• 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.
• NSK catalogues the contact-sealed version as 6205DDU (suffix DDU), 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. NSK's DDU lip design is single-lip contact, so grease life is longer than VV but drag torque is higher.
• The 25 mm bore puts 6205 in NSK's light industrial range; the standard pressed-steel cage and CN clearance cover most fractional-horsepower motor and small-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 15.4 kN dynamic load rating (C) and 7.85 kN static (C0), 6205 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 129 g, 6205 is light enough for hand assembly but should be pressed on with a fitting sleeve against the inner ring; do not strike the outer ring or cage with a hammer.
• The 25×52×15 mm envelope of 6205 gives a D/d ratio of 2.08 and 13.5 mm radial section height — a heavy NSK section built for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
• The 15.4/7.85 kN load ratings, mass 129 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6205DDU on the 25×52×15 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6205 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.
• Keep NSK bearings in the original packaging until fitting: the wrapper carries the production lot, and the unopened shelf life of greased sealed units is typically quoted at three to five years in dry, vibration-free storage.
• 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.