6204-ZZ-NTN bearing: complete specifications & equivalents

The 6204-ZZ-NTN is a ISO 15 radial bearing sized 20 x 47 x 14 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 = 47 mm d = 20 B = 14 mm side section front view
Principal dimensions: bore d 20 mm, outer diameter D 47 mm, width B 14 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 20 mm
Outer diameter D 47 mm
Width B 14 mm
Material GCr15
Seal / shield ZZ
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 14.2 kN
Basic static load rating C0 6.65 kN
Fatigue load limit Pu 0.51 kN
Limiting speed (mechanical) 12000 rpm
Operating temperature -40 to +120 °C
Mass 106 g
Manufacturer designation 6204ZZ
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 & 6200-series range

Bore d0.787 in
Outer diameter D1.85 in
Width B0.551 in
ISO bore code04
Radial section height (D−d)/213.5 mm
Smallest bore in 6200-series3 mm
Largest outer diameter in 6200-series540 mm
Width range across 6200-series2.5–85 mm
Bore position in 6200-series (smallest first)11 of 45
Bore above smallest 6200-series size17 mm

Mounting, lubrication & life for 6204-ZZ-NTN

Recommended fits & mounting

  • Rotating inner ring on a 20 mm shaft: k5; housing bore H7 for normal stationary-load outer rings. Reverse the logic if the outer ring rotates.
  • Fit by induction heating (max 120 °C) where practical — never drive the ring home through the rolling elements.
  • Keep shaft and housing fillet radii below the bearing chamfer so the 14 mm-wide ring seats square on its shoulder.

Lubrication strategy

Non-contact metal shields block coarse debris while running nearly as cool as open. No relubrication path on the standard execution; the shield cavity grease ages even though the steel is still serviceable.

Worked L10 life example (illustrative duty)

For ball bearings, L10h = (C/P)3 · 106 / (60·n). Taking an example radial equivalent load P = 3 kN at n = 1,500 r/min (a small belted motor duty — substitute the real equivalent load from the application calculation):

C = 14.2 kN → L10h ≈ 1,178 hours — a warning that this section is lightly rated for a 3 kN load; a heavier section at the same 20 mm bore is the usual fix

Choosing a section at the same 20 mm bore

SeriesOpen executionOD × widthC (kN)Limiting speed (r/min)
60xx6004-FAG42 × 1210.627,500
62xx6204-FAG47 × 1414.724,300
63xx6304-FAG52 × 1516.919,800
64xx6404-FAG72 × 1930.514,000
618xx61804-FAG32 × 74.033,500
619xx61904-FAG37 × 96.428,500
160xx1600442 × 87.926,000

A larger section is not a drop-in swap — OD and width change — and same-envelope seal variants are compared on the 20×47×14 envelope page. Match meaning, not the size chart alone: see what the cross-reference levels mean.

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6204-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-2RS-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-ZZ-FAG FAG full
Dimensions and internal design equivalent — standard interchange.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-RSR-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-ZZ-NSK NSK full
Dimensions and internal design equivalent — standard interchange.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-ZZ SKF full
Dimensions and internal design equivalent — standard interchange.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6204-RSR SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6204-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6204-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6204 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 20×47×14 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 6204-ZZ-NTN model number is decoded

6204-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 light 62xx section (diameter series 2 of ISO 15), multiplying bore code 04 by five gives the 20 mm bore; the 47 mm outside diameter and 14 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 20 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: 6204ZZ (suffix ZZ), two non-contact steel shields, mapped here from the industry-neutral -ZZ spelling.

Typical equipment & failure modes

Common applications

  • centrifugal pumps
  • small gearboxes
  • conveyors and drives
  • agricultural equipment

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
  • false brinelling from vibration while the shaft is stationary
  • fretting corrosion on a loose shaft seat

Selection pitfalls — read before you substitute

  • At a 20 mm bore, a shaft-seat burr or an overtight setscrew can score the thin inner ring of 6204-ZZ-NTN; check shaft finish and runout (target Ra ≤ 1.6 µm) before pressing it home.
  • At 20 mm bore the 62xx light series is the workhorse section; its 47×14 mm envelope is what most motor and gearbox seats are machined for, so any alternative section must be checked against both this OD and this width, not the bore alone.
  • ZZ shields are non-contact: 6204-ZZ-NTN blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 6204-2RS for that.
  • Do not wash 6204-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.
  • Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6200-series position can soften the mixture and leak — clean out the old fill before switching grease types.
  • Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
  • NTN catalogues the shielded version as 6204ZZ — 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 20 mm bore puts 6204 in NTN's light industrial range; the standard pressed-steel cage and CN clearance cover most fractional-horsepower motor and small-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.
  • NTN rates 6204 at 12000 r/min grease limiting speed — this is an electric-motor range; keep the grease fill at 25–35% of the free bearing volume and avoid mixing grease thickener types if regreasing through the seal lip.
  • NTN rates 6204 at 14.2 kN dynamic (C) and 6.65 kN static (C0), 0.51 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 106 g, 6204 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 20×47×14 mm envelope of 6204 gives a D/d ratio of 2.35 and 13.5 mm radial section height — a heavy section built for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
  • The 14.2/6.65 kN load ratings, 0.51 kN fatigue load limit Cu NTN lists the grease limiting speed at 12000 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 106 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6204ZZ on the 20×47×14 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6204 in a rated drive.
  • NTN's pressed-steel cage (no cage suffix) is the quiet standard for this size; for sustained running close to the limiting speed or for heavy shock duty, ask the NTN channel whether a machined-cage execution of 6204 is listed.
  • 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.

Frequently asked questions

What are the dimensions of a 6204-ZZ-NTN bearing?

A 6204-ZZ-NTN deep-groove ball bearing has a 20 mm bore, 47 mm outer diameter and 14 mm width (0.787 × 1.85 × 0.551 in), per ISO 15 boundary dimensions. It is fitted with two non-contact metallic shields.

How does the 6204 bore code work?

The last two digits of 6204 are bore code 04, giving 04 × 5 = 20 mm bore. The 47 mm outside diameter and 14 mm width follow the ISO 15 diameter series, not the bore code alone.

What does the ZZ suffix on 6204-ZZ mean?

ZZ means two non-contact sheet-metal shields, one each side. They retain factory grease and block coarse particles with little friction, but do not seal against liquids, fine dust or pressure washing.

What is the NTN suffix for a sealed 6204?

NTN uses suffix LLU for the contact rubber seal (catalogue number 6204ZZ), 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 20×47×14 mm ISO 15 envelope.

Is 6204ZZ 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.