61910-ZZ-NTN bearing: complete specifications & equivalents

The 61910-ZZ-NTN is a ISO 15 radial bearing sized 50 x 72 x 12 mm (bore x OD x width) with ZZ 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 = 72 mm d = 50 B = 12 mm side section front view
Principal dimensions: bore d 50 mm, outer diameter D 72 mm, width B 12 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 50 mm
Outer diameter D 72 mm
Width B 12 mm
Material GCr15
Seal / shield ZZ
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 14.9 kN
Basic static load rating C0 11.2 kN
Fatigue load limit Pu 0.77 kN
Limiting speed (mechanical) 6100 rpm
Operating temperature -40 to +120 °C
Mass 132 g
Manufacturer designation 6910ZZ
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 d1.969 in
Outer diameter D2.835 in
Width B0.472 in
ISO bore code10
Radial section height (D−d)/211 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)18 of 63
Bore above smallest 61900-series size47 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61910-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910-RSR-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910-ZZ NSK full
Dimensions and internal design equivalent — standard interchange.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61910-RSR SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 50×72×12 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 61910-ZZ-NTN model number is decoded

61910-ZZ carries two non-contact sheet-steel shields that hold the factory grease in and keep coarse debris out; they do not seal against liquids. Within the thin 619xx section (diameter series 9 of ISO 15), multiplying bore code 10 by five gives the 50 mm bore; the 72 mm outside diameter and 12 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 50 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. NTN catalogue order number: 6910ZZ (suffix ZZ), two non-contact steel shields, mapped here from the industry-neutral -ZZ spelling.

Typical equipment & failure modes

Common applications

  • lay shafts and idler shafts
  • textile machinery
  • packaging machinery
  • space-constrained gearboxes

Known failure patterns

  • fine-particle abrasion when non-contact shields let dust past in dirty duty
  • grease aging in the shield-for-life cavity with no relubrication path
  • fretting corrosion on a loose shaft seat
  • cage damage from operation beyond the limiting speed

Selection pitfalls — read before you substitute

  • Interference on a 50 mm shaft plus running heat consumes radial clearance: where the shaft runs hot or the fit is tight, order 61910 with C3 clearance and re-check the residual value after mounting.
  • The 619xx thin section (11.0 mm section height at 50 mm bore) trades load capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
  • ZZ shields are non-contact: 61910-ZZ-NTN blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 61910-2RS for that.
  • Do not wash 61910-ZZ-NTN in solvent before mounting: the grease inside the shielded cavity is the service fill, and solvent creeping past the shield gap strips it out.
  • Vibration during standstill brinells the raceways of a 50 mm bearing at ball spacing; if the machine sits idle next to running equipment, turn the shaft over periodically or isolate the arrangement.
  • Never mix components between two 61910-ZZ-NTN units: rings, cage and balls are factory-matched and are not field-interchangeable, even between identical designations.
  • NTN catalogues the shielded version as 6910ZZ — suffix ZZ, two non-contact steel shields. The industry-neutral page spelling is -ZZ; quote the NTN order number when buying through an NTN channel.
  • The 50 mm bore puts 61910 in NTN's general-purpose industrial range; the standard pressed-steel cage and CN clearance cover most electric-motor and pump duty, but for continuous high-speed use specify the LLH low-torque seal (not LLU) and confirm the housing allows the listed limiting speed.
  • At 6100 r/min the grease limiting speed for 61910 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
  • NTN rates 61910 at 14.9 kN dynamic (C) and 11.2 kN static (C0), 0.77 kN fatigue load limit Cu; this light-to-medium rating suits fractional-horsepower drives and instruments — for conveying or gearbox duty with shock loads, verify the equivalent dynamic load stays well below C.
  • At 132 g, 61910 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 50×72×12 mm envelope of 61910 gives a D/d ratio of 1.44 and 11.0 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 14.9/11.2 kN load ratings, 0.77 kN fatigue load limit Cu NTN lists the grease limiting speed at 6100 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 132 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6910ZZ on the 50×72×12 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61910 in a rated drive.
  • Order the C3 internal-clearance version (61910 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.
  • Standard catalogue stock of 61910 is the general-purpose execution; for low-noise motor duty NTN offers low-torque seal and special-grease variants in this size class, which are separate order numbers.

Frequently asked questions

What are the dimensions of a 61910-ZZ-NTN bearing?

A 61910-ZZ-NTN deep-groove ball bearing has a 50 mm bore, 72 mm outer diameter and 12 mm width (1.969 × 2.835 × 0.472 in), per ISO 15 boundary dimensions. It is fitted with two non-contact metallic shields.

What internal clearance does 61910-ZZ-NTN have?

Unless a clearance suffix says otherwise, 61910-ZZ-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 61910 and verify the residual clearance after mounting.

How should 61910-ZZ-NTN be mounted?

Apply the mounting force to the ring being fitted: on a 50 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 NTN suffix for a sealed 61910?

NTN uses suffix LLU for the contact rubber seal (catalogue number 6910ZZ), 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 50×72×12 mm ISO 15 envelope.

Does NTN offer 61910 with C3 clearance?

Yes — most NTN deep-groove sizes can be ordered with C3 internal clearance (suffix C3 follows the seal code). C3 suits tight fits and hot shafts; for normal fits at moderate temperature the standard CN clearance of 6910ZZ is the correct choice.

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.