430309 bearing: complete specifications & equivalents
The 430309 is a ANSI ABMA 19.2 radial bearing sized 45 x 100 x 60 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 45 mm |
| Outer diameter D | 100 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 212 kN |
| Basic static load rating C0 | 251 kN |
| Limiting speed (mechanical) | 3300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2170 g |
| Manufacturer designation | NTN 4T-430309 |
| 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-430-series range
| Bore d | 1.772 in |
|---|---|
| Outer diameter D | 3.937 in |
| Width B | 2.362 in |
| ISO bore code | 09 |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in 4t-430-series | 40 mm |
| Largest outer diameter in 4t-430-series | 870 mm |
| Width range across 4t-430-series | 45–310 mm |
| Bore position in 4t-430-series (smallest first) | 2 of 41 |
| Bore above smallest 4t-430-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 430309 | 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 430309 model number is decoded
4T-430309 belongs to the light-duty 430-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. With no letter suffix, 430309 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code. The 4.7 kN of dynamic capacity per millimetre of bore summarises the 212 kN rating over the 45 mm bore — compare substitution candidates on this ratio and on the 60 mm width. The internal clearance of 4T-430309 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 60 mm overall width is the finished dimension. Re-lubrication holes and grooves of the housing should line up with the cup's mid-width so fresh grease reaches both roller rows of 4T-430309.
Typical equipment & failure modes
Common applications
- construction-equipment swing and pivot shafts
- industrial gearbox shafts in a single locating position
- rolling-mill work-roll and backup auxiliary positions
- crane travel and hoist drum shafts
Known failure patterns
- roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant
- one-row flaking when a bent shaft concentrates the combined load on a single row of the pair
- overheated running after a field attempt to "tighten up" the factory-set internal clearance
- pressed-steel cage pocket wear from roller skid at light load and high speed
- indentation of both raceways by hard particles in an open, unsealed arrangement
Selection pitfalls — read before you substitute
- Gearbox positions of this 45 mm class rely on the preset clearance of 4T-430309; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.
- The 430 light plan keeps 4T-430309 narrower and faster than the 432 heavy execution of the same 45 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.
- Open 4T-430309 units have no seals: the housing must seal both rows or the 3,300 r/min grease figure is meaningless once contamination enters.
- The 212 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 430309 code including suffixes — U, X, DX, E1 and UTG variants share the 45 mm bore but are different articles with different internal geometry.
- The 212/251 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430309; 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-430309?
4T-430309 is a double-row tapered roller bearing of TDO (back-to-back) construction: 45 mm bore, 100 mm outside diameter and 60 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 212 kN, C0 251 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2.17 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 45 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-430309 belongs to the light-duty 430-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-430309 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 60 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 430309 mean?
With no letter suffix, 430309 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code.
Why does 4T-430309 list two speeds, 3,300 and 4,400 r/min?
The lower figure, 3,300 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430309 at 4,400 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.