323038UTG bearing: complete specifications & equivalents
The 323038UTG is a ANSI ABMA 19.2 radial bearing sized 190 x 290 x 75 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 190 mm |
| Outer diameter D | 290 mm |
| Width B | 75 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 790 kN |
| Basic static load rating C0 | 1110 kN |
| Fatigue load limit Pu | 104 kN |
| Limiting speed (mechanical) | 950 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 17900 g |
| Manufacturer designation | NTN 4T-323038UTG |
| Standard | ANSI ABMA 19.2 |
| Catalog version | NTN 2203E 2026-09-25 |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN 2203E 2026-09-25) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN 2203E 2026-09-25); 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 & 4t-432-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 11.417 in |
| Width B | 2.953 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 50 mm |
| Smallest bore in 4t-432-series | 40 mm |
| Largest outer diameter in 4t-432-series | 790 mm |
| Width range across 4t-432-series | 46–266 mm |
| Bore position in 4t-432-series (smallest first) | 23 of 39 |
| Bore above smallest 4t-432-series size | 150 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 323038UTG | 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 323038UTG model number is decoded
4T-323038UTG is an NTN double-row tapered roller bearing of TDO (back-to-back) construction: two cone assemblies against one double cup, supplied as a preset unit of 190×290×75 mm. Unlike a pair of single-row bearings, the TDO unit of 4T-323038UTG integrates both rows in one article: the 75 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. The 50.0 mm radial section over the 190 mm bore carries two roller rows across the 75 mm width; abutment shoulders must clear both cone bores and the double-cup OD. TDO construction means the two cone assemblies of 4T-323038UTG face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 190 mm shaft. Induction heating to max 120 °C is the standard fitting method at this 190 mm bore; driving the unit home through the rollers brinells both rows at once.
Typical equipment & failure modes
Common applications
- power-plant mill and fan shafts
- rolling-mill roll-neck and pinion-stand positions
- mine hoist and dragline drum shafts
- cement-plant mill and kiln drive trains
Known failure patterns
- edge loading on one row when the housing seats the double cup cocked across its width
- preload loss and hammering noise when the cup clamping loosens and the unit gains axial float
- brinelling of both rows from a mounting blow transmitted through the roller complements
- cage fatigue after continuous running near the grease limiting speed without oil cooling
- water-induced pitting when washdown reaches the open unit without external seals
Selection pitfalls — read before you substitute
- At 190 mm bore the 4T-323038UTG unit needs hydraulic or crane-assisted fitting and a verified oil supply; manual methods cannot control seating at the 790 kN C level.
- The 432 heavy plan gives 4T-323038UTG its 75 mm width and 790 kN rating at the 190 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 104 kN Cu.
- The internal clearance of 4T-323038UTG is factory-set: no end-play adjustment exists at mounting, and any attempt to set preload with a shaft nut overloads one row.
- Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-323038UTG feeds the two roller complements evenly; a single-side feed starves the far row.
- The 50.0 mm section leaves little room for oversized shaft fillets; follow the 2203E chamfer table for 4T-323038UTG or the cones bottom out on the radius.
- The 790/1110 kN ratings and 104 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-323038UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 4T-323038UTG?
4T-323038UTG is a double-row tapered roller bearing of TDO (back-to-back) construction: 190 mm bore, 290 mm outside diameter and 75 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 790 kN, C0 1110 kN, Cu 104 kN, grease limiting speed 950 r/min, oil speed 1,400 r/min, mass about 17.9 kg. It is an open, preset-clearance unit with pressed-steel cages.
What is the difference between the NTN 430 and 432 double-row series at 190 mm bore?
Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-323038UTG belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family).
Can the internal clearance of 4T-323038UTG be adjusted at mounting?
No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 75 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row.
What do the suffix letters on 323038UTG mean?
Suffix reading on 323038UTG: UTG marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design, printed with the ＊ symbol ahead of the order number; suffixed variants are separate order numbers and are not interchangeable articles.
Why does 4T-323038UTG list two speeds, 950 and 1,400 r/min?
The lower figure, 950 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-323038UTG at 1,400 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN 2203E 2026-09-25 on 2026-10-01. Read our editorial & correction policy.