24128EMD1 bearing: complete specifications & equivalents
The 24128EMD1 is a ISO 15 radial bearing sized 140 x 225 x 85 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 140 mm |
| Outer diameter D | 225 mm |
| Width B | 85 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 951 kN |
| Basic static load rating C0 | 1280 kN |
| Fatigue load limit Pu | 53.3 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 12900 g |
| Manufacturer designation | NTN 24128EMD1 |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 24100-series range
| Bore d | 5.512 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 3.346 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 42.5 mm |
| Smallest bore in 24100-series | 100 mm |
| Largest outer diameter in 24100-series | 1150 mm |
| Width range across 24100-series | 65–438 mm |
| Bore position in 24100-series (smallest first) | 5 of 32 |
| Bore above smallest 24100-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 24128EMK30D1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 24128EMK30D1 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement. |
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 24128EMD1 model number is decoded
24128EMD1 belongs to the 24100 series of NTN spherical rollers and carries the ＊ ULTAGE new-generation mark in the 2203E table: self-aligning, high radial capacity, moderate axial load in either direction. The leading digits are the ISO 15 dimension series (24100 series); the bore code resolves to 140 mm (two-digit code ×5, with the 00–03 exception table), and 225 mm OD / 85 mm width follow the general plan. The 42.5 mm radial section over the 140 mm bore carries two roller rows; capacity per millimetre of bore is about 6.8 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. Equivalent-load planning keeps a radial plus moderate axial combination on 24128EMD1; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Fillet radii on shaft and housing must clear the ring chamfers of the 85 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.
Typical equipment & failure modes
Common applications
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
Known failure patterns
- raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
- machined EM cage wear from inadequate oil film at the cage-guiding surfaces
- roller-end smearing during skidding starts under light load and high viscosity grease
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
- water-induced pitting in washdown or outdoor duty without effective external seals
Selection pitfalls — read before you substitute
- At 140 mm bore 24128EMD1 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.
- Adapter-sleeve mounting requires the correct sleeve series and locknut for the 140 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K seats.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 951 kN rating no longer applies.
- Do not confuse EA and EM at the same number: 24128EMD1 carries EM machined-brass-cage; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 140×225 mm envelope is identical.
- The cylindrical-bore 24128EMD1 and its tapered-bore counterpart 24128EMK30D1 share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
- The 951/1280 kN ratings, 53.3 kN Pu and 12900 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 24128EMD1 (EM machined-brass-cage/D1); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives.
Frequently asked questions
What are the dimensions and catalogue data of 24128EMD1?
24128EMD1 is an NTN double-row spherical roller bearing to ISO 15: 140 mm bore, 225 mm OD and 85 mm width (5.512 × 8.858 × 3.346 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 951 kN, C0 1280 kN, Pu 53.3 kN, grease limiting speed 1,700 r/min, oil 2,200 r/min, mass about 12900 g. It is open, with one-piece machined brass cage (EM high-capacity design).
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
24128EMD1 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 24128EMK30D1 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting.
What do EA and EM mean on NTN spherical roller bearings?
EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 24128EMD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 24128EMD1?
D1 is NTN's outer-ring lubrication feature: an annular groove with oil holes around the outer ring, aligned with a housing grease port so lubricant reaches both roller rows directly. 24128EMD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 24128EMD1 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 951 kN C / 1280 kN C0 — but sustained pure axial load is not recommended because it unloads one row.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.