61817-2RS-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 61817-2RS-NSK model number is decoded

61817-2RS 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 17 by five gives the 85 mm bore; the 110 mm outside diameter and 13 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 85 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 6817DDU (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

• Mount this 85 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
• Only 12.5 mm of radial section separates bore and OD on the 618xx series at 85 mm: ring flex from clamping or an oval housing bore transfers straight into raceway stress, so seat roundness matters more here than on a 6217.
• Heat is the enemy of the sealed 61817-2RS: 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.
• Never wash a sealed 61817-2RS-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.
• Suffixes stack in a defined order — clearance follows the seal code, e.g. 61817-2RS-NSK-C3. No clearance suffix means normal CN clearance.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 13 mm-wide ring of 61817-2RS-NSK drags the lip and overheats it.
• NSK catalogues the contact-sealed version as 6817DDU (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.
• At 85 mm bore 61817 is in NSK's medium industrial range; the pressed-steel cage is standard, but large-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.
• At 20.6 kN dynamic load rating (C) and 20 kN static (C0), 61817 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 263 g, 61817 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 85×110×13 mm envelope of 61817 gives a D/d ratio of 1.29 and only 12.5 mm radial section height — this is an ultra-thin section in NSK's E1103 catalogue 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 20.6/20 kN load ratings, mass 263 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6817DDU on the 85×110×13 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61817 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.
• Standard P0 runout from NSK is adequate up to the catalogue limiting speed on ground shaft seats; spindle or instrument positions should specify P6/P5 accuracy explicitly — it is a different order code, not a sorting of standard stock.
• When replacing a failed unit, inspect the shaft and housing seats before fitting the new 61817 — a new bearing pressed onto a worn or oval seat reproduces the original failure mode in a fraction of its expected life.