23128EMD1 bearing: complete specifications & equivalents
The 23128EMD1 is a ISO 15 radial bearing sized 140 x 225 x 68 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 | 68 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 802 kN |
| Basic static load rating C0 | 1030 kN |
| Fatigue load limit Pu | 53.1 kN |
| Limiting speed (mechanical) | 1800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 10300 g |
| Manufacturer designation | NTN 23128EMD1 |
| 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 & 23100-series range
| Bore d | 5.512 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 2.677 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 42.5 mm |
| Smallest bore in 23100-series | 100 mm |
| Largest outer diameter in 23100-series | 1420 mm |
| Width range across 23100-series | 52–412 mm |
| Bore position in 23100-series (smallest first) | 5 of 36 |
| Bore above smallest 23100-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23128EMKD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 23128EMKD1 (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 23128EMD1 model number is decoded
23128EMD1 belongs to the 23100 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. On the NTN nameplate the suffix cluster after the size reads in order: cage design (EM), bore (cylindrical), lubrication feature (D1); 23128EMD1 is assembled exactly in that order. Pu 53.1 kN is the catalogue fatigue load limit for 23128EMD1, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Equivalent-load planning keeps a radial plus moderate axial combination on 23128EMD1; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Supply grease through the D1 feature during commissioning and at the calculated interval, rotating the 140 mm bore assembly by hand to distribute it across both rows.
Typical equipment & failure modes
Common applications
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
Known failure patterns
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- cage damage when a mounting force is applied through the roller set instead of the ring face
- roller-end smearing during skidding starts under light load and high viscosity grease
- rolling-contact fatigue after the catalogue L10 life at the actual load
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- At 140 mm bore 23128EMD1 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.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 23128EMD1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Do not confuse EA and EM at the same number: 23128EMD1 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.
- K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 140 mm bearing, and drive-up procedures differ.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 23128EMD1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 802/1030 kN ratings, 53.1 kN Pu and 10300 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23128EMD1 (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 23128EMD1?
23128EMD1 is an NTN double-row spherical roller bearing to ISO 15: 140 mm bore, 225 mm OD and 68 mm width (5.512 × 8.858 × 2.677 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 802 kN, C0 1030 kN, Pu 53.1 kN, grease limiting speed 1,800 r/min, oil 2,200 r/min, mass about 10300 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?
23128EMD1 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 23128EMKD1 (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. 23128EMD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23128EMD1?
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. 23128EMD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23128EMD1 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 802 kN C / 1030 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.