30212-NTN bearing: complete specifications & equivalents
The 30212-NTN is a ISO 355 radial bearing sized 60 x 110 x 23.75 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 60 mm |
| Outer diameter D | 110 mm |
| Width B | 23.75 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 116 kN |
| Basic static load rating C0 | 125 kN |
| Limiting speed (mechanical) | 3400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 929 g |
| Manufacturer designation | NTN 30212 |
| 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 & 30200-series range
| Bore d | 2.362 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 0.935 in |
| ISO bore code | 12 |
| Radial section height (D−d)/2 | 25 mm |
| Smallest bore in 30200-series | 15 mm |
| Largest outer diameter in 30200-series | 580 mm |
| Width range across 30200-series | 11.75–104 mm |
| Bore position in 30200-series (smallest first) | 12 of 37 |
| Bore above smallest 30200-series size | 45 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30212 | 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. |
| 30212-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 30212-NTN model number is decoded
NTN supplies this 60 mm bore tapered roller position as 30212: one cone assembly, one cup, line-contact rollers and a steel cage, rated 116 kN basic dynamic and 125 kN static on the standard-section 30200 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3EB, which is the maker-neutral cross-reference for the 60×110 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 60 mm bore the application supplies the seals and the grease fill or oil supply to the 3EB ISO 355 assembly. The 1.9 kN-per-mm-bore capacity figure for 30212 summarises the 116 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30212; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.
Typical equipment & failure modes
Common applications
- paper-machine press-section rolls
- large agricultural and forestry machine axles
- heavy industrial gearboxes and crane travel drives
- rolling-mill auxiliary and pinion-stand shafts
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
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 929 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The standard-section 30200 family at 60 mm bore (110×23.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,500 r/min oil ceiling.
- ISO 355 makes the 60×110 mm envelope interchangeable but not the ratings: NTN prints 116/125 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.
- Replacing one half of an adjusted pair without resetting end play negates the 23.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30212 or the ring will bottom out on the radius instead of the shoulder face.
- The 116/125 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30212 (ISO 355 3EB); 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 30212?
30212 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 110 mm outside diameter and 23.75 mm assembled width T (2.362 × 4.331 × 0.935 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 125 kN (2203E prints no Pu for this size), grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 929 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30212?
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 (30212); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30212 designation encode the 60 mm bore and what is 3EB?
last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 23.75 mm assembled T follow the ISO 355 dimension-series plan. 3EB 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 30212 list two speeds, 3,400 and 4,500 r/min?
The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30212 at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 30212 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.