30260UTG bearing: complete specifications & equivalents
The 30260UTG is a ISO 355 radial bearing sized 300 x 540 x 96 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 300 mm |
| Outer diameter D | 540 mm |
| Width B | 96 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1820 kN |
| Basic static load rating C0 | 2220 kN |
| Fatigue load limit Pu | 176 kN |
| Limiting speed (mechanical) | 580 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 83500 g |
| Manufacturer designation | NTN 30260UTG |
| 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 | 11.811 in |
|---|---|
| Outer diameter D | 21.26 in |
| Width B | 3.78 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 120 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) | 36 of 37 |
| Bore above smallest 30200-series size | 285 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30260UTG | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the 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 30260UTG model number is decoded
For a 300 mm shaft with a thrust component, NTN lists 30260UTG, a metric 4T tapered roller bearing of 1820 kN C and 2220 kN C0 inside the 540 mm OD, 96 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30260UTG by the metric ISO 355 number: 300 mm bore, 540 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 300 mm bore the application supplies the seals and the grease fill or oil supply to the ISO 355 assembly. The 120.0 mm section height over the 300 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 300 mm pair is misadjusted and the 96 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- heavy haul railway traction gearboxes
- large marine propulsion reduction gears
- cement-plant kiln and mill drive trains
- rolling-mill roll-neck and gearbox positions
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- smearing on the roller large ends and cone rib after a dry start with preload but no oil film
- flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- water-induced pitting when the open bearing is exposed to washdown without external seals
Selection pitfalls — read before you substitute
- At 300 mm bore the 30260UTG 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 1820 kN C level.
- The standard-section 30200 family at 300 mm bore (540×96 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 830 r/min oil ceiling.
- The 120.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30260UTG or the ring will bottom out on the radius instead of the shoulder face.
- Do not confuse T (96 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.
- The 120.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30260UTG or the ring will bottom out on the radius instead of the shoulder face.
- The 1820/2220 kN ratings and 176 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30260UTG; 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 30260UTG?
30260UTG is a metric 4T tapered roller bearing to ISO 355: 300 mm bore, 540 mm outside diameter and 96 mm assembled width T (11.811 × 21.26 × 3.78 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1820 kN, C0 2220 kN, Pu 176 kN, grease limiting speed 580 r/min, oil speed 830 r/min, mass about 83500 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30260UTG?
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 (30260UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30260UTG designation encode the 300 mm bore?
last two digits 60 are the ISO bore code, ×5 = 300 mm (codes 00–03 use the 10/12/15/17 exception table). The 540 mm OD and 96 mm assembled T follow the ISO 355 dimension-series plan.
Why does 30260UTG list two speeds, 580 and 830 r/min?
The lower figure, 580 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30260UTG at 830 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 30260UTG mean?
Suffix reading on 30260UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; 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.