61815-ZZ-NTN bearing: complete specifications & equivalents

The 61815-ZZ-NTN is a ISO 15 radial bearing sized 75 x 95 x 10 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 = 95 mm d = 75 B = 10 mm side section front view
Principal dimensions: bore d 75 mm, outer diameter D 95 mm, width B 10 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 75 mm
Outer diameter D 95 mm
Width B 10 mm
Material GCr15
Seal / shield ZZ
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 13.9 kN
Basic static load rating C0 12.9 kN
Fatigue load limit Pu 0.85 kN
Limiting speed (mechanical) 6400 rpm
Operating temperature -40 to +120 °C
Mass 145 g
Manufacturer designation 6815ZZ
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 & 61800-series range

Bore d2.953 in
Outer diameter D3.74 in
Width B0.394 in
ISO bore code15
Radial section height (D−d)/210 mm
Smallest bore in 61800-series1 mm
Largest outer diameter in 61800-series1820 mm
Width range across 61800-series1–140 mm
Bore position in 61800-series (smallest first)26 of 74
Bore above smallest 61800-series size74 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61815-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815-RSR-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815-ZZ NSK full
Dimensions and internal design equivalent — standard interchange.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61815-RSR SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 75×95×10 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 61815-ZZ-NTN model number is decoded

In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61815 carries bore code 15 = 75 mm. Outside diameter 95 mm and width 10 mm come from the ISO 15 boundary-dimensions general plan. Suffix -ZZ denotes two non-contact metallic shields; they retain grease and block coarse debris but are not liquid-tight. For normal-load mounting with a rotating inner ring on a 75 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. NTN catalogue order number: 6815ZZ (suffix ZZ), two non-contact steel shields, mapped here from the industry-neutral -ZZ spelling.

Typical equipment & failure modes

Common applications

  • packaging machinery
  • space-constrained gearboxes
  • clutch and transmission assemblies
  • robotics and automation joints

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
  • brinelling from static overload or hammering during mounting
  • false brinelling from vibration while the shaft is stationary

Selection pitfalls — read before you substitute

  • Interference on a 75 mm shaft plus running heat consumes radial clearance: where the shaft runs hot or the fit is tight, order 61815 with C3 clearance and re-check the residual value after mounting.
  • Only 10.0 mm of radial section separates bore and OD on the 618xx series at 75 mm: ring flex from clamping or an oval housing bore transfers straight into raceway stress, so seat roundness matters more here than on a 6215.
  • ZZ shields are non-contact: 61815-ZZ-NTN blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 61815-2RS for that.
  • Shielded 61815-ZZ-NTN units are typically greased for life; prying the shields out for regreasing usually bends them and leaves a gap that throws grease in service.
  • Do not quieten a noisy bearing by preloading it: the 61800-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
  • Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 10 mm-wide ring of 61815-ZZ-NTN drags the lip and overheats it.
  • NTN catalogues the shielded version as 6815ZZ — 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.
  • At 75 mm bore 61815 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-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 NTN channel if the application sees impact loads.
  • At 6400 r/min the grease limiting speed for 61815 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
  • NTN rates 61815 at 13.9 kN dynamic (C) and 12.9 kN static (C0), 0.85 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 145 g, 61815 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 75×95×10 mm envelope of 61815 gives a D/d ratio of 1.27 and only 10.0 mm radial section height — this is an ultra-thin section 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 13.9/12.9 kN load ratings, 0.85 kN fatigue load limit Cu NTN lists the grease limiting speed at 6400 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 145 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6815ZZ on the 75×95×10 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61815 in a rated drive.
  • NTN date-codes its packaging; rotate stock first-in-first-out, because the grease inside sealed units ages on the shelf — after three to five years of storage, check the grease condition before putting the bearing into service.
  • 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 61815-ZZ-NTN bearing?

A 61815-ZZ-NTN deep-groove ball bearing has a 75 mm bore, 95 mm outer diameter and 10 mm width (2.953 × 3.74 × 0.394 in), per ISO 15 boundary dimensions. It is fitted with two non-contact metallic shields.

Are 61815 bearings from different brands interchangeable?

For boundary dimensions, yes: every brand's 61815 uses the same ISO 15 envelope (75×95×10 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 61815-ZZ-NTN have?

Unless a clearance suffix says otherwise, 61815-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 61815 and verify the residual clearance after mounting.

What is the NTN suffix for a sealed 61815?

NTN uses suffix LLU for the contact rubber seal (catalogue number 6815ZZ), 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 75×95×10 mm ISO 15 envelope.

Is 6815ZZ a current NTN production size?

The NTN 2203-series catalogue lists it as a standard size; availability of specific seal executions (ZZ, LLB/LLF, LLH, LLU) varies by region and stock — confirm with an NTN distributor before specifying spares.

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.