33010-NTN bearing: complete specifications & equivalents
The 33010-NTN is a ISO 355 radial bearing sized 50 x 80 x 24 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 50 mm |
| Outer diameter D | 80 mm |
| Width B | 24 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 77.5 kN |
| Basic static load rating C0 | 103 kN |
| Limiting speed (mechanical) | 4400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 440 g |
| Manufacturer designation | NTN 33010 |
| 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 | 1.969 in |
|---|---|
| Outer diameter D | 3.15 in |
| Width B | 0.945 in |
| ISO bore code | 10 |
| Radial section height (D−d)/2 | 15 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) | 6 of 24 |
| Bore above smallest 33000-series size | 25 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 33010 | 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. |
| 33010-DF | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue. |
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 33010-NTN model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33010 denotes the slim 33000 family of metric tapered roller bearings, 50 mm bore, 80 mm outside diameter and 24 mm assembled width T (1.969 × 3.15 × 0.945 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 50 mm; 80 mm OD and 24 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 33010 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The two speed columns differ by a factor of .76 (grease/limiting 4,400 vs oil 5,800 r/min); heat generation at the cone rib decides which lubrication a real 33010 arrangement can sustain. When pairing 33010 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.
Typical equipment & failure modes
Common applications
- industrial gearbox and speed-reducer shafts
- bevel and helical pinion drives with high thrust component
- pump and compressor drive shafts carrying combined load
- machine-tool gearbox and headstock shafts
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft
- smearing on the roller large ends and cone rib after a dry start with preload but no oil film
- cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling
- false brinelling on a stationary paired set exposed to external vibration
Selection pitfalls — read before you substitute
- Hub and pinion bearings of this 50 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 33010.
- The thin 24 mm section of 33010 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 50 mm bore smears the roller ends against the rib.
- Never fit the 50 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- ISO 355 makes the 50×80 mm envelope interchangeable but not the ratings: NTN prints 77.5/103 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.
- Do not confuse T (24 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.
- The 77.5/103 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33010 (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 33010?
33010 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 80 mm outside diameter and 24 mm assembled width T (1.969 × 3.15 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 103 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 440 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 33010?
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 (33010); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 33010 designation encode the 50 mm bore and what is 2CE?
last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 24 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 33010 list two speeds, 4,400 and 5,800 r/min?
The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33010 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 33010 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.