32968E1 bearing: complete specifications & equivalents
The 32968E1 is a ISO 355 radial bearing sized 340 x 460 x 76 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 340 mm |
| Outer diameter D | 460 mm |
| Width B | 76 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1010 kN |
| Basic static load rating C0 | 1980 kN |
| Fatigue load limit Pu | 159 kN |
| Limiting speed (mechanical) | 630 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 34000 g |
| Manufacturer designation | NTN 32968E1 |
| 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 & 32900-series range
| Bore d | 13.386 in |
|---|---|
| Outer diameter D | 18.11 in |
| Width B | 2.992 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 60 mm |
| Smallest bore in 32900-series | 35 mm |
| Largest outer diameter in 32900-series | 600 mm |
| Width range across 32900-series | 14–100 mm |
| Bore position in 32900-series (smallest first) | 32 of 37 |
| Bore above smallest 32900-series size | 305 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32968E1 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 32968E1 model number is decoded
32968E1 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 340×460 mm ISO 355 envelope, with 76 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 340×460 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 1010 kN C the bearing offers about 3.0 kN of dynamic capacity per millimetre of the 340 mm bore — compare any substitution on this ratio and the 76 mm assembled T, not on bore alone. The 60.0 mm section height over the 340 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. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 340 mm pair is misadjusted and the 76 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- cement-plant kiln and mill drive trains
- rolling-mill roll-neck and gearbox positions
- large crusher and SAG/AG-mill drive shafts
- wind-turbine gearbox and main-shaft arrangements
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- 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
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows
Selection pitfalls — read before you substitute
- At 340 mm bore the 32968E1 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1010 kN C level.
- The thin 76 mm section of 32968E1 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 340 mm bore smears the roller ends against the 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 340 mm shoulder geometry, because retrofitting flips the cups.
- Never fit the 340 mm cone by hammering the 460 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- Open 32968E1 units have no seals: a wheel-hub or gearbox application needs external sealing or the 630 r/min grease figure is meaningless once water reaches the cone rib.
- The 1010/1980 kN ratings and 159 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32968E1; 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 32968E1?
32968E1 is a metric 4T tapered roller bearing to ISO 355: 340 mm bore, 460 mm outside diameter and 76 mm assembled width T (13.386 × 18.11 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1010 kN, C0 1980 kN, Pu 159 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 34000 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32968E1?
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 (32968E1); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32968E1 designation encode the 340 mm bore?
last two digits E1 are the ISO bore code, ×5 = 340 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan.
Why does 32968E1 list two speeds, 630 and 900 r/min?
The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32968E1 at 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 32968E1 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.