33206-NTN bearing: complete specifications & equivalents
The 33206-NTN is a ISO 355 radial bearing sized 30 x 62 x 25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 30 mm |
| Outer diameter D | 62 mm |
| Width B | 25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 72 kN |
| Basic static load rating C0 | 77 kN |
| Limiting speed (mechanical) | 6300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 348 g |
| Manufacturer designation | NTN 33206 |
| Standard | ISO 355 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 33200-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 2.441 in |
| Width B | 0.984 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 16 mm |
| Smallest bore in 33200-series | 25 mm |
| Largest outer diameter in 33200-series | 180 mm |
| Width range across 33200-series | 22–63 mm |
| Bore position in 33200-series (smallest first) | 3 of 18 |
| Bore above smallest 33200-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 33206 | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 33206-NTN model number is decoded
33206 is the NTN 4T catalogue entry for a 30×62×25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. With no letter after the number, 33206 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. Selection: C 72 kN against C0 77 kN gives a C0/C ratio of 1.07 for the 30 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 30 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33206.
Typical equipment & failure modes
Common applications
- machine-tool gearbox and headstock shafts
- axle final-drive and differential positions
- construction-equipment wheel and pivot hubs
- truck and bus wheel hubs in paired arrangements
Known failure patterns
- cone-raceway spalling at the large rib when preload is set too high for the lubricant film
- preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play
- rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- rolling-contact fatigue after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33206.
- The medium-wide 33200 family at 30 mm bore (62×25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,400 r/min oil ceiling.
- Open 33206 units have no seals: a wheel-hub or gearbox application needs external sealing or the 6,300 r/min grease figure is meaningless once water reaches the cone rib.
- Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 30 mm shoulder geometry, because retrofitting flips the cups.
- ISO 355 makes the 30×62 mm envelope interchangeable but not the ratings: NTN prints 72/77 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.
- The 72/77 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33206 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 33206?
33206 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 62 mm outside diameter and 25 mm assembled width T (1.181 × 2.441 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 77 kN (2203E prints no Pu for this size), grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 348 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 33206?
4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33206); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 33206 designation encode the 30 mm bore and what is 2DE?
last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark.
Why does 33206 list two speeds, 6,300 and 8,400 r/min?
The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33206 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 33206 mean?
It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.