423124 bearing: complete specifications & equivalents
The 423124 is a ANSI ABMA 19.2 radial bearing sized 120 x 200 x 78 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 120 mm |
| Outer diameter D | 200 mm |
| Width B | 78 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 415 kN |
| Basic static load rating C0 | 610 kN |
| Fatigue load limit Pu | 64.5 kN |
| Limiting speed (mechanical) | 1500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 8690 g |
| Manufacturer designation | NTN 4T-423124 |
| 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 | 4.724 in |
|---|---|
| Outer diameter D | 7.874 in |
| Width B | 3.071 in |
| ISO bore code | 24 |
| Radial section height (D−d)/2 | 40 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) | 16 of 41 |
| Bore above smallest 4t-430-series size | 80 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 423124 | 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 423124 model number is decoded
4T-423124 is the NTN 4T catalogue entry for a 120×200×78 mm double-row tapered roller bearing — the TDO arrangement reacts radial load plus thrust in both directions without a second bearing. Reading the designation: the last two digits 24 are the bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table); the leading digits place the bearing in the light-duty 430-family TDO double-row series. Selection: C 415 kN against C0 610 kN gives a C0/C ratio of 1.47; the two rows of 4T-423124 share the combined load as one bearing position. TDO construction means the two cone assemblies of 4T-423124 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 120 mm shaft. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-423124; the double cup must seat square across its full 78 mm width.
Typical equipment & failure modes
Common applications
- heavy press and forging-machine drives
- large shredder and recycler main shafts
- power-plant mill and fan shafts
- rolling-mill roll-neck and pinion-stand positions
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 damage when the unit is lifted by one cone instead of the double cup during fitting
- false brinelling on a stored or standby unit exposed to vibration
Selection pitfalls — read before you substitute
- At 120 mm bore the 4T-423124 unit needs hydraulic or crane-assisted fitting and a verified oil supply; manual methods cannot control seating at the 415 kN C level.
- The 430 light plan keeps 4T-423124 narrower and faster than the 432 heavy execution of the same 120 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.
- An unloaded 4T-423124 near 1,500 r/min lets rollers skid; ensure a minimum load or light spring preload on high-speed positions.
- Never interchange a TDO double-row unit with two single-row bearings of similar size: the 78 mm width, load spread and clearance logic of 4T-423124 are unit-specific.
- The 40.0 mm section leaves little room for oversized shaft fillets; follow the 2203E chamfer table for 4T-423124 or the cones bottom out on the radius.
- The 415/610 kN ratings and 64.5 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-423124; 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-423124?
4T-423124 is a double-row tapered roller bearing of TDO (back-to-back) construction: 120 mm bore, 200 mm outside diameter and 78 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 415 kN, C0 610 kN, Cu 64.5 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 8.69 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 120 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-423124 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-423124 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 78 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 423124 mean?
With no letter suffix, 423124 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code.
Why does 4T-423124 list two speeds, 1,500 and 2,000 r/min?
The lower figure, 1,500 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-423124 at 2,000 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.