30214-NTN bearing: complete specifications & equivalents
The 30214-NTN is a ISO 355 radial bearing sized 70 x 125 x 26.25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 70 mm |
| Outer diameter D | 125 mm |
| Width B | 26.25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 146 kN |
| Basic static load rating C0 | 162 kN |
| Limiting speed (mechanical) | 2900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1300 g |
| Manufacturer designation | NTN 30214 |
| 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 | 2.756 in |
|---|---|
| Outer diameter D | 4.921 in |
| Width B | 1.033 in |
| ISO bore code | 14 |
| Radial section height (D−d)/2 | 27.5 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) | 14 of 37 |
| Bore above smallest 30200-series size | 55 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30214 | 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 30214-NTN model number is decoded
The NTN 2203E table prints 30214 in the standard-section 30200 family: 70 mm bore, 125 mm cup OD, 26.25 mm T, with a grease limiting speed of 2,900 r/min and an oil-lubricated ceiling of 3,900 r/min. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 26.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 27.5 mm radial section carries the roller complement across the 70–125 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 27.5 mm section height over the 70 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30214; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.
Typical equipment & failure modes
Common applications
- large conveyor and bucket-elevator pulleys
- mineral-processing feeder and crusher auxiliaries
- marine winch and deck-machinery shafts
- paper-machine press-section rolls
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
- Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1300 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The standard-section 30200 family at 70 mm bore (125×26.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.
- Open 30214 units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.
- The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30214 or the ring will bottom out on the radius instead of the shoulder face.
- The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30214 by size alone can deliver the wrong contact-angle execution for a pinion position.
- The 146/162 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30214 (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 30214?
30214 is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 125 mm outside diameter and 26.25 mm assembled width T (2.756 × 4.921 × 1.033 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 146 kN, C0 162 kN (2203E prints no Pu for this size), grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 1300 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30214?
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 (30214); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30214 designation encode the 70 mm bore and what is 3EB?
last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 26.25 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 30214 list two speeds, 2,900 and 3,900 r/min?
The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30214 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 30214 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.