323048UTG bearing: complete specifications & equivalents
The 323048UTG is a ANSI ABMA 19.2 radial bearing sized 240 x 360 x 92 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 240 mm |
| Outer diameter D | 360 mm |
| Width B | 92 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1170 kN |
| Basic static load rating C0 | 1770 kN |
| Fatigue load limit Pu | 155 kN |
| Limiting speed (mechanical) | 730 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 32500 g |
| Manufacturer designation | NTN 4T-323048UTG |
| 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 | 9.449 in |
|---|---|
| Outer diameter D | 14.173 in |
| Width B | 3.622 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 60 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) | 26 of 39 |
| Bore above smallest 4t-432-series size | 200 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 323048UTG | 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 323048UTG model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-323048UTG denotes the heavy-duty 432-family TDO double-row series — a 240 mm bore double-row tapered unit rated 1170 kN basic dynamic and 1770 kN static. Large sizes continue the plans under different leading digits: 4130/4131 and 4230/4231 belong to the 430-family dimension plan, while 3230/3231 continue the 432 heavy plan — 323048UTG reads accordingly. Speed planning uses both catalogue columns: grease 730 r/min is the mechanical ceiling, oil 1,000 r/min with oil lubrication — a 270 r/min margin at this size. Because the unit is preset, mounting 4T-323048UTG resembles mounting a double-row spherical or cylindrical bearing: seat the unit, clamp axially to the stated end cover torque, and verify rotation — no end-play measurement is required. With a rotating shaft a m6/n6 seat on the 240 mm journal and a located cup in the housing are typical practice for 4T-323048UTG.
Typical equipment & failure modes
Common applications
- mine hoist and dragline drum shafts
- cement-plant mill and kiln drive trains
- port-crane hoist and luffing gearboxes
- heavy press and forging-machine drives
Known failure patterns
- roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant
- 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
- thermal distress when the oil supply sized for one row starves the second row
Selection pitfalls — read before you substitute
- At 240 mm bore the 4T-323048UTG unit needs hydraulic or crane-assisted fitting and a verified oil supply; manual methods cannot control seating at the 1170 kN C level.
- The 432 heavy plan gives 4T-323048UTG its 92 mm width and 1170 kN rating at the 240 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 155 kN Cu.
- The 1170 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.
- Order by the full 323048UTG code including suffixes — U, X, DX, E1 and UTG variants share the 240 mm bore but are different articles with different internal geometry.
- Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-323048UTG feeds the two roller complements evenly; a single-side feed starves the far row.
- The 1170/1770 kN ratings and 155 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-323048UTG; 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-323048UTG?
4T-323048UTG is a double-row tapered roller bearing of TDO (back-to-back) construction: 240 mm bore, 360 mm outside diameter and 92 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 1170 kN, C0 1770 kN, Cu 155 kN, grease limiting speed 730 r/min, oil speed 1,000 r/min, mass about 32.5 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 240 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-323048UTG 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-323048UTG 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 92 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 323048UTG mean?
Suffix reading on 323048UTG: 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-323048UTG list two speeds, 730 and 1,000 r/min?
The lower figure, 730 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-323048UTG at 1,000 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.