61930-2RS bearing: complete specifications & equivalents
The 61930-2RS is a ISO 15 radial bearing sized 150 x 210 x 28 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NSK |
| Bore diameter d | 150 mm |
| Outer diameter D | 210 mm |
| Width B | 28 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 93.5 kN |
| Basic static load rating C0 | 90.5 kN |
| Mass | 3010 g |
| Manufacturer designation | NSK 6930DDU |
| 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 & 61900-series range
| Bore d | 5.906 in |
|---|---|
| Outer diameter D | 8.268 in |
| Width B | 1.102 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 61900-series | 10 mm |
| Largest outer diameter in 61900-series | 420 mm |
| Width range across 61900-series | 6–56 mm |
| Bore position in 61900-series (smallest first) | 27 of 37 |
| Bore above smallest 61900-series size | 140 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61930 | ISO-INTERCHANGE | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 envelope interchange; NSK suffix 6930DDU maps to industry-neutral 2RS. Verify seal design, grease and speed rating per brand catalogue. |
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 61930-2RS model number is decoded
In the 61900-series (ISO 15 diameter series 9) the last two digits encode the bore: 61930 carries bore code 30 = 150 mm. Outside diameter 210 mm and width 28 mm come from the ISO 15 boundary-dimensions general plan. Suffix -2RS denotes two contact-type elastomer seals over a lifetime grease fill; the sealing lips add drag compared with open or shielded versions. For normal-load mounting with a rotating inner ring on a 150 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- textile machinery
- packaging machinery
- space-constrained gearboxes
- clutch and transmission assemblies
Known failure patterns
- seal-lip hardening and loss of pre-grease in sustained high-temperature service
- grease-life expiry in the sealed-for-life cavity (no relubrication path)
- 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 150 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.
- The 619xx thin section (30.0 mm section height at 150 mm bore) trades load capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
- Contact seals add drag and heat: 61930-2RS runs slower and cooler-limited than the open 61930; 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 61930-2RS in solvent or press it home via the outer ring; solvent destroys the grease thickener and mounting force through the seal deforms the lip.
- Do not quieten a noisy bearing by preloading it: the 61900-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
- NSK catalogues the contact-sealed version as 6930DDU (suffix DDU), the NSK equivalent of the industry-neutral -2RS spelling on this page; it is greased for life and the contacting lip lowers the speed ceiling versus the open bearing.
- The 93.5/90.5 kN ratings, mass 3010 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6930DDU; this seal/size combination has no counterpart in the SKF 17000 extract used elsewhere on this site, so the page rests on a single manufacturer source — internal geometry and ratings legitimately differ between brands, so re-verify before substituting in a rated drive.
Frequently asked questions
What are the dimensions of a 61930-2RS bearing?
A 61930-2RS deep-groove ball bearing has a 150 mm bore, 210 mm outer diameter and 28 mm width (5.906 × 8.268 × 1.102 in), per ISO 15 boundary dimensions. It is fitted with two contact rubber seals and is normally pre-greased.
How does the 61930 bore code work?
The last two digits of 61930 are bore code 30, giving 30 × 5 = 150 mm bore. The 210 mm outside diameter and 28 mm width follow the ISO 15 diameter series, not the bore code alone.
What does the 2RS suffix on 61930-2RS mean?
2RS means two contact elastomer seals, one each side, usually over a lifetime grease fill. Sealing against dust and moisture is better than ZZ shields, but the lip drag lowers the speed and temperature ceiling.
How does the 61900 compare with other series at the same 150 mm bore?
619 is a thin section one step above 618: 210×28 mm with a 30.0 mm radial section at 150 mm bore; a 6230 on the same bore is substantially larger and more heavily rated.
What is the NSK designation and catalogue data for 61930-2RS?
In the NSK Rolling Bearings catalogue (E1103 Part C) this size is listed as 6930DDU — two contacting rubber seals over a lifetime grease fill (NSK suffix DDU), 150×210×28 mm per ISO 15. Quoted values: C 93.5 kN, C0 90.5 kN, mass 3010 g. The industry-neutral page spelling 61930-2RS follows the seal-suffix convention used across this site, not NSK order-number spelling. Reference and limiting speeds are not tabulated in the E1103 dimension tables used here; consult NSK speed tables before high-speed service.
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.