23128EMKD1 bearing: complete specifications & equivalents
The 23128EMKD1 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 | 10000 g |
| Manufacturer designation | NTN 23128EMKD1 |
| 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 |
|---|---|---|---|
| 23128EMD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23128EMD1 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. 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 23128EMKD1 model number is decoded
23128EMKD1 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 140×225×68 mm to ISO 15, with one-piece machined brass cage (EM high-capacity design). The leading digits are the ISO 15 dimension series (23100 series); the bore code resolves to 140 mm (two-digit code ×5, with the 00–03 exception table), and 225 mm OD / 68 mm width follow the general plan. Open by design, 23128EMKD1 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. 140 mm bore is 5.512 in and 225 mm OD is 8.858 in; the ISO 15 envelope swaps between brands, but the 802/1030 kN ratings and cage design are NTN 2203E values. Mount 23128EMKD1 on its adapter or withdrawal sleeve on the 140 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.
Typical equipment & failure modes
Common applications
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
- offshore and marine propulsion shaftlines
Known failure patterns
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- machined EM cage wear from inadequate oil film at the cage-guiding surfaces
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range
- brinelling from static overload or a hammer blow during sleeve mounting
Selection pitfalls — read before you substitute
- At 140 mm bore 23128EMKD1 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.
- Do not confuse EA and EM at the same number: 23128EMKD1 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.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 802 kN rating no longer applies.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 802 kN rating no longer applies.
- The 802/1030 kN ratings, 53.1 kN Pu and 10000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23128EMKD1 (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 23128EMKD1?
23128EMKD1 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 10000 g. It is open, with one-piece machined brass cage (EM high-capacity design) and a 1:12 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K denotes a 1:12 tapered bore. 23128EMKD1 mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 23128EMD1.
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. 23128EMKD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23128EMKD1?
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. 23128EMKD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23128EMKD1 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.