30244UTG bearing: complete specifications & equivalents
The 30244UTG is a ISO 355 radial bearing sized 220 x 400 x 72 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 220 mm |
| Outer diameter D | 400 mm |
| Width B | 72 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1050 kN |
| Basic static load rating C0 | 1220 kN |
| Fatigue load limit Pu | 106 kN |
| Limiting speed (mechanical) | 840 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 34800 g |
| Manufacturer designation | NTN 30244UTG |
| 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 | 8.661 in |
|---|---|
| Outer diameter D | 15.748 in |
| Width B | 2.835 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 90 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) | 32 of 37 |
| Bore above smallest 30200-series size | 205 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30244UTG | 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 30244UTG model number is decoded
The NTN 2203E table prints 30244UTG in the standard-section 30200 family: 220 mm bore, 400 mm cup OD, 72 mm T, with a grease limiting speed of 840 r/min and an oil-lubricated ceiling of 1,200 r/min. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 220 mm; 400 mm OD and 72 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 1050 kN C the bearing offers about 4.8 kN of dynamic capacity per millimetre of the 220 mm bore — compare any substitution on this ratio and the 72 mm assembled T, not on bore alone. The 4.8 kN-per-mm-bore capacity figure for 30244UTG summarises the 1050 kN rating over 220 mm bore; use it to sanity-check an interchange candidate before swapping brands. Fillet radii must clear the ring chamfers of the 400 mm cup and 220 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.
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
- 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
- brinell marks on cone and cup raceways from impact during handling or hammering during fitting
Selection pitfalls — read before you substitute
- At 220 mm bore the 30244UTG 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 1050 kN C level.
- The standard-section 30200 family at 220 mm bore (400×72 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,200 r/min oil ceiling.
- Never fit the 220 mm cone by hammering the 400 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- Replacing one half of an adjusted pair without resetting end play negates the 72 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- Open 30244UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 840 r/min grease figure is meaningless once water reaches the cone rib.
- The 1050/1220 kN ratings and 106 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30244UTG; 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 30244UTG?
30244UTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 400 mm outside diameter and 72 mm assembled width T (8.661 × 15.748 × 2.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1050 kN, C0 1220 kN, Pu 106 kN, grease limiting speed 840 r/min, oil speed 1,200 r/min, mass about 34800 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30244UTG?
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 (30244UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30244UTG designation encode the 220 mm bore?
last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 72 mm assembled T follow the ISO 355 dimension-series plan.
Why does 30244UTG list two speeds, 840 and 1,200 r/min?
The lower figure, 840 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30244UTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 30244UTG mean?
Suffix reading on 30244UTG: 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.