32028XU bearing: complete specifications & equivalents
The 32028XU is a ISO 355 radial bearing sized 140 x 210 x 45 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 140 mm |
| Outer diameter D | 210 mm |
| Width B | 45 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 365 kN |
| Basic static load rating C0 | 580 kN |
| Fatigue load limit Pu | 60 kN |
| Limiting speed (mechanical) | 1600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5320 g |
| Manufacturer designation | NTN 32028XU |
| 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 & 32000-series range
| Bore d | 5.512 in |
|---|---|
| Outer diameter D | 8.268 in |
| Width B | 1.772 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 35 mm |
| Smallest bore in 32000-series | 20 mm |
| Largest outer diameter in 32000-series | 650 mm |
| Width range across 32000-series | 15–130 mm |
| Bore position in 32000-series (smallest first) | 25 of 43 |
| Bore above smallest 32000-series size | 120 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32028XU | 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 32028XU model number is decoded
32028XU 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 140×210 mm ISO 355 envelope, with 45 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32028XU resolves to 140 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 365/580 kN (C/C0) the static rating is about 1.59× C, typical of tapered bearings proportioned for heavy combined duty. The fatigue load limit Pu printed for 32028XU is 60 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Fillet radii must clear the ring chamfers of the 210 mm cup and 140 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.
Typical equipment & failure modes
Common applications
- offshore crane and drawworks drums
- heavy haul railway traction gearboxes
- large marine propulsion reduction gears
- cement-plant kiln and mill drive trains
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
- rolling-contact fatigue after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- At 140 mm bore the 32028XU 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 365 kN C level.
- The thin 45 mm section of 32028XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 140 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 140 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.
- On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 140 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 32028XU at a large fraction of 1,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.
- The 365/580 kN ratings and 60 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32028XU (ISO 355 4DC); 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 32028XU?
32028XU is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 210 mm outside diameter and 45 mm assembled width T (5.512 × 8.268 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 365 kN, C0 580 kN, Pu 60 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 5320 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32028XU?
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 (32028XU); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32028XU designation encode the 140 mm bore and what is 4DC?
last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 210 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 4DC 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 32028XU list two speeds, 1,600 and 2,100 r/min?
The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32028XU at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32028XU mean?
Suffix reading on 32028XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles.
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.