423128 bearing: complete specifications & equivalents

The 423128 is a ANSI ABMA 19.2 radial bearing sized 140 x 225 x 84 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 225 mm d = 140 B = 84 mm side section front view
Principal dimensions: bore d 140 mm, outer diameter D 225 mm, width B 84 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 140 mm
Outer diameter D 225 mm
Width B 84 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 435 kN
Basic static load rating C0 650 kN
Fatigue load limit Pu 66 kN
Limiting speed (mechanical) 1200 rpm
Operating temperature -40 to +120 °C
Mass 11100 g
Manufacturer designation NTN 4T-423128
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 5.512 in
Outer diameter D 8.858 in
Width B 3.307 in
ISO bore code 28
Radial section height (D−d)/2 42.5 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) 18 of 41
Bore above smallest 4t-430-series size 100 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
423128 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 423128 model number is decoded

4T-423128 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 140×225×84 mm. 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 140 mm bore the 432 execution carries a wider, heavier section than the 430. The fatigue load limit Cu printed for 4T-423128 is 66 kN — the equivalent-load floor below which high reliability is expected even under contamination in the adjusted-life equation. TDO construction means the two cone assemblies of 4T-423128 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 140 mm shaft. Induction heating to max 120 °C is the standard fitting method at this 140 mm bore; driving the unit home through the rollers brinells both rows at once.

Typical equipment & failure modes

Common applications

  • large shredder and recycler main shafts
  • power-plant mill and fan shafts
  • rolling-mill roll-neck and pinion-stand positions
  • mine hoist and dragline drum shafts

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
  • pressed-steel cage pocket wear from roller skid at light load and high speed
  • false brinelling on a stored or standby unit exposed to vibration

Selection pitfalls — read before you substitute

  • At 140 mm bore the 4T-423128 unit needs hydraulic or crane-assisted fitting and a verified oil supply; manual methods cannot control seating at the 435 kN C level.
  • The 430 light plan keeps 4T-423128 narrower and faster than the 432 heavy execution of the same 140 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.
  • Clamping the double cup with a cocked end cover pinches one row: tighten the 225 mm OD clamping uniformly around the circumference.
  • Clamping the double cup with a cocked end cover pinches one row: tighten the 225 mm OD clamping uniformly around the circumference.
  • Open 4T-423128 units have no seals: the housing must seal both rows or the 1,200 r/min grease figure is meaningless once contamination enters.
  • The 435/650 kN ratings and 66 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-423128; 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-423128?

4T-423128 is a double-row tapered roller bearing of TDO (back-to-back) construction: 140 mm bore, 225 mm outside diameter and 84 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 435 kN, C0 650 kN, Cu 66 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 11.1 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 140 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-423128 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-423128 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 84 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 423128 mean?

With no letter suffix, 423128 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code.

Why does 4T-423128 list two speeds, 1,200 and 1,700 r/min?

The lower figure, 1,200 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-423128 at 1,700 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.