432318U bearing: complete specifications & equivalents
The 432318U is a ANSI ABMA 19.2 radial bearing sized 90 x 190 x 144 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 90 mm |
| Outer diameter D | 190 mm |
| Width B | 144 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 855 kN |
| Basic static load rating C0 | 1190 kN |
| Fatigue load limit Pu | 131 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 18300 g |
| Manufacturer designation | NTN 4T-432318U |
| 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 | 3.543 in |
|---|---|
| Outer diameter D | 7.48 in |
| Width B | 5.669 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) | 11 of 39 |
| Bore above smallest 4t-432-series size | 50 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 432318U | 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 432318U model number is decoded
4T-432318U belongs to the heavy-duty 432-family TDO double-row series of NTN double-row tapered roller bearings; the unit is mounted as one article and its internal clearance is set at the factory, not on the shaft. The 4T- prefix is NTN's tapered roller quality mark; 430 numbers the light TDO plan and 432 the heavy TDO plan — at the same 90 mm bore the 432 execution carries a wider, heavier section than the 430. Double-row capacity is not twice a single-row bearing: the printed 855 kN C already accounts for load sharing between the two rows of 4T-432318U, so apply it directly in the L10 calculation. TDO construction means the two cone assemblies of 4T-432318U 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 90 mm shaft. At 855 kN C the unit offers about 9.5 kN per millimetre of the 90 mm bore — heavy-section TDO rows of this class run warm, so confirm oil availability before working near 2,300 r/min.
Typical equipment & failure modes
Common applications
- marine winch and deck-machinery shafts
- bulk-handling stacker/reclaimer travel drives
- large mixer and agitator shafts
- heavy gearbox and mill drive shafts
Known failure patterns
- edge loading on one row when the housing seats the double cup cocked across its width
- overheated running after a field attempt to "tighten up" the factory-set internal clearance
- one-row flaking when a bent shaft concentrates the combined load on a single row of the pair
- cage damage when the unit is lifted by one cone instead of the double cup during fitting
- water-induced pitting when washdown reaches the open unit without external seals
Selection pitfalls — read before you substitute
- Mount the 90 mm unit by induction heating (max 120 °C); at 18.3 kg a cocked lift damages the cages and ribs before the bearing ever runs.
- The 432 heavy plan gives 4T-432318U its 144 mm width and 855 kN rating at the 90 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 131 kN Cu.
- Open 4T-432318U units have no seals: the housing must seal both rows or the 1,700 r/min grease figure is meaningless once contamination enters.
- At inspection do not mix the cone assemblies of 4T-432318U with another unit; rows are ground together and re-matching is not guaranteed in the field.
- The 50.0 mm section leaves little room for oversized shaft fillets; follow the 2203E chamfer table for 4T-432318U or the cones bottom out on the radius.
- The 855/1190 kN ratings and 131 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432318U; 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-432318U?
4T-432318U is a double-row tapered roller bearing of TDO (back-to-back) construction: 90 mm bore, 190 mm outside diameter and 144 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 855 kN, C0 1190 kN, Cu 131 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 18.3 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 90 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-432318U 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-432318U 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 144 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 432318U mean?
Suffix reading on 432318U: U marks the uprated/reinforced internal design, a separate order number with higher capacity than the basic execution; suffixed variants are separate order numbers and are not interchangeable articles.
Why does 4T-432318U list two speeds, 1,700 and 2,300 r/min?
The lower figure, 1,700 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432318U at 2,300 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.