320-32X bearing: complete specifications & equivalents
The 320-32X is a ISO 355 radial bearing sized 32 x 58 x 17 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 32 mm |
| Outer diameter D | 58 mm |
| Width B | 17 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 41 kN |
| Basic static load rating C0 | 46.5 kN |
| Limiting speed (mechanical) | 6600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 188 g |
| Manufacturer designation | NTN 320/32X |
| 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 | 1.26 in |
|---|---|
| Outer diameter D | 2.283 in |
| Width B | 0.669 in |
| ISO bore code | 20 |
| Radial section height (D−d)/2 | 13 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) | 6 of 43 |
| Bore above smallest 32000-series size | 12 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 320-22 | 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. |
| 320-28 | 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. |
| 320-32 | 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 320-32X model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 320/32X denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 32 mm bore, 58 mm outside diameter and 17 mm assembled width T (1.26 × 2.283 × 0.669 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 320/32X by the metric ISO 355 number (ISO series abbreviation 4CC): 32 mm bore, 58 mm OD. 2203E lists two speed ceilings for 320/32X: 6,600 r/min with grease lubrication (the limiting speed) and 8,700 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Grease relubrication at 6,600 r/min limiting speed targets the rib contact; if the drive needs 8,700 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 320/32X washes out and the rib/roller-end contact smears on the first wet or dusty shift.
Typical equipment & failure modes
Common applications
- axle final-drive and differential positions
- construction-equipment wheel and pivot hubs
- truck and bus wheel hubs in paired arrangements
- industrial gearbox and speed-reducer shafts
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- 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 fatigue when the pair is run continuously near the grease limiting speed without oil cooling
- rolling-contact fatigue after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Hub and pinion bearings of this 32 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 320/32X.
- The thin 17 mm section of 320/32X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 32 mm bore smears the roller ends against the rib.
- Grease packs must leave free volume in the 17 mm-wide set; over-greasing a paired bearing churning at the 8,700 r/min oil-band speed raises temperature and destroys the preload setting.
- Never fit the 32 mm cone by hammering the 58 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- Grease packs must leave free volume in the 17 mm-wide set; over-greasing a paired bearing churning at the 8,700 r/min oil-band speed raises temperature and destroys the preload setting.
- The 41/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 320/32X (ISO 355 4CC); 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 320/32X?
320/32X is a metric 4T tapered roller bearing to ISO 355: 32 mm bore, 58 mm outside diameter and 17 mm assembled width T (1.26 × 2.283 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41 kN, C0 46.5 kN (2203E prints no Pu for this size), grease limiting speed 6,600 r/min, oil speed 8,700 r/min, mass about 188 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 320/32X?
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 (320/32X); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 320/32X designation encode the 32 mm bore and what is 4CC?
32 mm bore is printed directly after the slash in the slash-size convention. The 58 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 4CC 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 320/32X list two speeds, 6,600 and 8,700 r/min?
The lower figure, 6,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 320/32X at 8,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 320/32X mean?
Suffix reading on 320/32X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); 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.