61930-2RS-NTN bearing: complete specifications & equivalents

The 61930-2RS-NTN 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.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 210 mm d = 150 B = 28 mm side section front view
Principal dimensions: bore d 150 mm, outer diameter D 210 mm, width B 28 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
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, stamped ribbon (J-type)
Basic dynamic load rating C 94 kN
Basic static load rating C0 90.5 kN
Fatigue load limit Pu 4.55 kN
Limiting speed (mechanical) 1700 rpm
Operating temperature -40 to +120 °C
Mass 2470 g
Manufacturer designation 6930LLU
Standard ISO 15
Catalog version NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)
Last verified 2026-09-25

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.

Dimensions in inches & 61900-series range

Bore d5.906 in
Outer diameter D8.268 in
Width B1.102 in
ISO bore code30
Radial section height (D−d)/230 mm
Smallest bore in 61900-series3 mm
Largest outer diameter in 61900-series1120 mm
Width range across 61900-series3–118 mm
Bore position in 61900-series (smallest first)34 of 63
Bore above smallest 61900-series size147 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61930-2RS NSK full
Dimensions and internal design equivalent — standard interchange.
Same 150×210×28 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61930-ZZ NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 150×210×28 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61930 NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 150×210×28 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61930-MA SKF full
Dimensions and internal design equivalent — standard interchange.
Same 150×210×28 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 61930-2RS-NTN model number is decoded

61930-2RS 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 thin 619xx section (diameter series 9 of ISO 15), multiplying bore code 30 by five gives the 150 mm bore; the 210 mm outside diameter and 28 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 150 mm shaft under normal load, catalogue practice seats it on a m6 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. NTN's contact-seal catalogue number is 6930LLU (suffix LLU, or LLH low-torque variant), mapped here from the industry-neutral -2RS spelling; the contacting lip lowers the speed ceiling versus the open bearing.

Typical equipment & failure modes

Common applications

  • space-constrained gearboxes
  • clutch and transmission assemblies
  • robotics and automation joints
  • lay shafts and idler shafts

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

  • At 150 mm bore the ring mass is significant: heat 61930 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
  • 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.
  • Heat is the enemy of the sealed 61930-2RS: 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 61930-2RS-NTN 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. 61930-2RS-NTN-C3. No clearance suffix means normal CN clearance.
  • Deep-groove ball bearings tolerate only minutes of misalignment; if the 210 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 61930-2RS-NTN.
  • NTN catalogues the contact-sealed version as 6930LLU (suffix LU), 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.
  • The 150 mm bore places 61930 at the lower end of NTN's large-size range; at these diameters the pressed-steel cage is speed-limited and NTN commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NTN distributor, and do not extrapolate small-bore speed ratings to this size.
  • NTN lists the grease limiting speed at 1700 r/min for 61930; this is a large or heavy-section size where centrifugal force and cage inertia cap the speed — for higher shaft speeds either step to a smaller bearing on the same bore or consult NTN for an oil-lubricated, machined-cage variant.
  • At 94 kN dynamic load rating (C) and 90.5 kN static (C0), 4.55 kN fatigue load limit Cu, 61930 is a heavy-load bearing for industrial gearboxes and large conveyors; NTN expects a machined brass cage (suffix M) at this rating for shock duty, and the static C0 must be checked against any mounting or lifting loads.
  • At 2470 g (2.5 kg), 61930 needs mechanical handling for mounting; NTN recommends induction heating the inner ring (max 120 °C) rather than pressing cold, and a lifting eye if the housing is pre-assembled.
  • The 150×210×28 mm envelope of 61930 gives a D/d ratio of 1.40 and 30.0 mm radial section height — this 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 94/90.5 kN load ratings, 4.55 kN fatigue load limit Cu NTN lists the grease limiting speed at 1700 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 2470 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6930LLU on the 150×210×28 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61930 in a rated drive.
  • Factory-fill grease in NTN sealed units is a general-duty lithium-soap grease; food-grade, low-temperature and high-temperature fills are request options at order time, because LLU/LLB units are not meant to be opened and re-greased in the field.
  • Two NTN bearings of the same designation from different production lots can carry minor internal-geometry revisions; for paired or preloaded arrangements on one shaft, order a single lot through the NTN distributor.

Frequently asked questions

What are the dimensions of a 61930-2RS-NTN bearing?

A 61930-2RS-NTN 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.

Are 61930 bearings from different brands interchangeable?

For boundary dimensions, yes: every brand's 61930 uses the same ISO 15 envelope (150×210×28 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting. Seal suffixes also differ by brand (2RS, DDU, LLU, 2RSL and similar).

What internal clearance does 61930-2RS-NTN have?

Unless a clearance suffix says otherwise, 61930-2RS-NTN 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 61930 and verify the residual clearance after mounting.

What is the NTN suffix for a sealed 61930?

NTN uses suffix LLU for the contact rubber seal (catalogue number 6930LLU), LLB/LLF for non-contact rubber seals, LLH for the low-torque contact seal and ZZ for steel shields. The industry-neutral spellings on this page (-2RS / -RSR / -ZZ) map to those NTN suffixes while keeping the 150×210×28 mm ISO 15 envelope.

What cage does NTN fit in 6930LLU?

Standard is a pressed-steel cage with no suffix; larger sizes or shock-loaded duty can be supplied with a machined brass cage (suffix M) as a separate order number. The catalogue figures quoted here are for the pressed-steel execution.

Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) on 2026-09-25. Read our editorial & correction policy.