61803-RSR-NSK bearing: complete specifications & equivalents
The 61803-RSR-NSK is a ISO 15 radial bearing sized 17 x 26 x 5 mm (bore x OD x width) with RSR sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NSK |
| Bore diameter d | 17 mm |
| Outer diameter D | 26 mm |
| Width B | 5 mm |
| Material | GCr15 |
| Seal / shield | RSR |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 2.89 kN |
| Basic static load rating C0 | 1.57 kN |
| Operating temperature | -40 to +150 °C |
| Mass | 7 g |
| Manufacturer designation | NSK 6803VV |
| Standard | ISO 15 |
| Catalog version | NSK Rolling Bearings E1103 Part C |
| Last verified | 2026-09-24 |
Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24
Dimensions in inches & 61800-series range
| Bore d | 0.669 in |
|---|---|
| Outer diameter D | 1.024 in |
| Width B | 0.197 in |
| ISO bore code | 03 |
| Radial section height (D−d)/2 | 4.5 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 14 of 74 |
| Bore above smallest 61800-series size | 16 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61803-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-2RS-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-ZZ-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-RSR-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-RSR | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61803-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| W61803-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| W61803-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17×26×5 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
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 61803-RSR-NSK model number is decoded
61803-RSR uses two non-contact elastomer lips with very low drag; coarse debris stays out, but the bearing is not liquid-tight. Within the extra-thin 618xx section (diameter series 8 of ISO 15), multiplying bore code 17 by five gives the 17 mm bore; the 26 mm outside diameter and 5 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 17 mm shaft under normal load, catalogue practice seats it on a j5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. NSK's non-contact seal suffix is VV (catalogue number 6803VV), mapped here from the industry-neutral -RSR spelling; speed capability is close to the open bearing but VV is not liquid-tight.
Typical equipment & failure modes
Common applications
- clutch and transmission assemblies
- robotics and automation joints
- lay shafts and idler shafts
- textile machinery
Known failure patterns
- ingress of fine dust or moisture past the non-contact lip in dirty or wet duty (RSR is not liquid-tight)
- lip-lubricant starvation if the bearing runs dry for extended periods
- brinelling from static overload or hammering during mounting
- false brinelling from vibration while the shaft is stationary
Selection pitfalls — read before you substitute
- Mount this 17 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 4.5 mm of radial section separates bore and OD on the 618xx series at 17 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.
- RSR low-friction seals on 61803-RSR-NSK run faster than contact-seal 61803-2RS but let fine dust and moisture past the non-contact lip; in dirty or wet duty specify 61803-2RS instead.
- The non-contact lip of 61803-RSR-NSK does not retain a lifetime grease fill the way a contact seal does; confirm the regreasing interval for the 17 mm bore position before relying on it as sealed-for-life.
- Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 5 mm-wide ring of 61803-RSR-NSK drags the lip and overheats it.
- Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 61800-series position can soften the mixture and leak — clean out the old fill before switching grease types.
- NSK catalogues this low-friction non-contact seal as 6803VV (suffix VV), mapped here from the industry-neutral -RSR spelling. NSK rates its speed capability close to the open bearing, but VV is not liquid-tight — for wet or fine-dust duty step up to the DDU contact seal (industry-neutral -2RS).
- At 17 mm bore the 61803 sits in NSK's small-bore range; NSK ships these sizes with a pressed-steel cage and P0 tolerance as standard, and NSK's EA (extra-precision) or P5 class is a special-order upgrade for spindle duty — do not assume catalogue P0 figures hold for instrument use without an NSK engineering check.
- At 2.89 kN dynamic load rating (C) and 1.57 kN static (C0), 61803 is a light-load NSK bearing: the L10 life at catalogue C is short above a few kN of equivalent load, so size up to a 62-series on the same bore if the application sees shock or frequent starts.
- At only 7 g, 61803 is a lightweight NSK bearing that can be handled by hand; still, press it onto the shaft with a sleeve against the inner ring — never through the balls or outer ring.
- The 17×26×5 mm envelope of 61803 gives a D/d ratio of 1.53 and 4.5 mm radial section height — this NSK thin section saves space but is sensitive to misalignment and shock; confirm the housing stays round within IT7 and the shaft does not deflect past the raceway contact angle under load.
- The 2.89/1.57 kN load ratings, mass 7 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6803VV on the 17×26×5 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61803 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.
- When replacing a failed unit, inspect the shaft and housing seats before fitting the new 61803 — a new bearing pressed onto a worn or oval seat reproduces the original failure mode in a fraction of its expected life.
- 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.
Frequently asked questions
What are the dimensions of a 61803-RSR-NSK bearing?
A 61803-RSR-NSK deep-groove ball bearing has a 17 mm bore, 26 mm outer diameter and 5 mm width (0.669 × 1.024 × 0.197 in), per ISO 15 boundary dimensions. It is fitted with two low-friction non-contact rubber seals.
What internal clearance does 61803-RSR-NSK have?
Unless a clearance suffix says otherwise, 61803-RSR-NSK is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 61803 and verify the residual clearance after mounting.
How should 61803-RSR-NSK be mounted?
Apply the mounting force to the ring being fitted: on a 17 mm shaft seat the press load must pass through the inner-ring face only. A fitting sleeve and an arbor press are normally sufficient at this size. Never strike the outer ring, the cage or the seals.
What is the NSK suffix for a sealed 61803?
NSK uses suffix DDU for the contact rubber seal (catalogue number 6803VV), VV for the non-contact rubber seal, and ZZ for steel shields. The industry-neutral spellings on this page (-2RS / -RSR / -ZZ) map to those NSK suffixes while keeping the 17×26×5 mm ISO 15 envelope.
Does NSK offer 61803 with C3 clearance?
NSK lists C3 (and C4) internal-clearance options for most deep-groove sizes under the same base designation; the clearance is fixed at manufacture, so specify it at order time rather than planning to adjust later.
Reviewed & verified by the MPN Base engineering desk against source catalog NSK Rolling Bearings E1103 Part C on 2026-09-24. Read our editorial & correction policy.