33005 bearing: complete specifications & equivalents
The 33005 is a ISO 355 radial bearing sized 25 x 47 x 17 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 25 mm |
| Outer diameter D | 47 mm |
| Width B | 17 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 36 kN |
| Basic static load rating C0 | 40.5 kN |
| Limiting speed (mechanical) | 8000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 130 g |
| Manufacturer designation | NTN 33005 |
| 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 & 33000-series range
| Bore d | 0.984 in |
|---|---|
| Outer diameter D | 1.85 in |
| Width B | 0.669 in |
| ISO bore code | 05 |
| Radial section height (D−d)/2 | 11 mm |
| Smallest bore in 33000-series | 25 mm |
| Largest outer diameter in 33000-series | 225 mm |
| Width range across 33000-series | 17–59 mm |
| Bore position in 33000-series (smallest first) | 1 of 24 |
| Bore above smallest 33000-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 33005 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the 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 33005 model number is decoded
NTN supplies this 25 mm bore tapered roller position as 33005: one cone assembly, one cup, line-contact rollers and a steel cage, rated 36 kN basic dynamic and 40.5 kN static on the slim 33000 family. The last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 36 kN against C0 40.5 kN gives a C0/C ratio of 1.13 for the 25 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33005; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.
Typical equipment & failure modes
Common applications
- small gearbox input shafts with combined load
- scooter and light-powersport wheel and gear positions
- small conveyor pulley shafts
- steering-knuckle and kingpin positions
Known failure patterns
- cone-raceway spalling at the large rib when preload is set too high for the lubricant film
- rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair
- preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 33005 pair with a dial indicator rather than by feel.
- The thin 17 mm section of 33005 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 25 mm bore smears the roller ends against the rib.
- On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 25 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.
- Minimum load matters at high speed: an unloaded 33005 at a large fraction of 8,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.
- Replacing one half of an adjusted pair without resetting end play negates the 17 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- The 36/40.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33005 (ISO 355 2CE); 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 33005?
33005 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 47 mm outside diameter and 17 mm assembled width T (0.984 × 1.85 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 36 kN, C0 40.5 kN (2203E prints no Pu for this size), grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 130 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 33005?
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 (33005); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 33005 designation encode the 25 mm bore and what is 2CE?
last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 2CE 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 33005 list two speeds, 8,000 and 11,000 r/min?
The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33005 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 33005 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.