30240UUTG bearing: complete specifications & equivalents
The 30240UUTG is a ISO 355 radial bearing sized 200 x 360 x 64 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 200 mm |
| Outer diameter D | 360 mm |
| Width B | 64 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 | 1110 kN |
| Fatigue load limit Pu | 99 kN |
| Limiting speed (mechanical) | 950 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 25200 g |
| Manufacturer designation | NTN 30240UUTG |
| 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 | 7.874 in |
|---|---|
| Outer diameter D | 14.173 in |
| Width B | 2.52 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 80 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) | 31 of 37 |
| Bore above smallest 30200-series size | 185 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30240UUTG | 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 30240UUTG model number is decoded
The NTN 2203E table prints 30240UUTG in the standard-section 30200 family: 200 mm bore, 360 mm cup OD, 64 mm T, with a grease limiting speed of 950 r/min and an oil-lubricated ceiling of 1,300 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30240UUTG by the metric ISO 355 number (ISO series abbreviation 4GB): 200 mm bore, 360 mm OD. Individually mounted, 30240UUTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 80.0 mm section height over the 200 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 200 mm pair is misadjusted and the 64 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
- 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
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- At 200 mm bore the 30240UUTG 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 standard-section 30200 family at 200 mm bore (360×64 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,300 r/min oil ceiling.
- Never fit the 200 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- Minimum load matters at high speed: an unloaded 30240UUTG at a large fraction of 950 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.
- Never fit the 200 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- The 1010/1110 kN ratings and 99 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30240UUTG (ISO 355 4GB); 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 30240UUTG?
30240UUTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 360 mm outside diameter and 64 mm assembled width T (7.874 × 14.173 × 2.52 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1010 kN, C0 1110 kN, Pu 99 kN, grease limiting speed 950 r/min, oil speed 1,300 r/min, mass about 25200 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30240UUTG?
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 (30240UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30240UUTG designation encode the 200 mm bore and what is 4GB?
last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 64 mm assembled T follow the ISO 355 dimension-series plan. 4GB 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 30240UUTG list two speeds, 950 and 1,300 r/min?
The lower figure, 950 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30240UUTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 30240UUTG mean?
Suffix reading on 30240UUTG: the UUTG 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.