23056EMKD1 bearing: complete specifications & equivalents
The 23056EMKD1 is a ISO 15 radial bearing sized 280 x 420 x 106 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 280 mm |
| Outer diameter D | 420 mm |
| Width B | 106 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 2170 kN |
| Basic static load rating C0 | 3150 kN |
| Fatigue load limit Pu | 155 kN |
| Limiting speed (mechanical) | 960 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 49700 g |
| Manufacturer designation | NTN 23056EMKD1 |
| 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 & 23000-series range
| Bore d | 11.024 in |
|---|---|
| Outer diameter D | 16.535 in |
| Width B | 4.173 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in 23000-series | 70 mm |
| Largest outer diameter in 23000-series | 1580 mm |
| Width range across 23000-series | 27–345 mm |
| Bore position in 23000-series (smallest first) | 21 of 46 |
| Bore above smallest 23000-series size | 210 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23056EMD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23056EMD1 — 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 23056EMKD1 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 23056EMKD1 denotes the 280 mm bore spherical roller bearing (2170 kN C / 3150 kN C0) in the 23000 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 280 mm (two-digit code ×5, with the 00–03 exception table), and 420 mm OD / 106 mm width follow the general plan. Open by design, 23056EMKD1 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. 280 mm bore is 11.024 in and 420 mm OD is 16.535 in; the ISO 15 envelope swaps between brands, but the 2170/3150 kN ratings and cage design are NTN 2203E values. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.
Typical equipment & failure modes
Common applications
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
- offshore and marine propulsion shaftlines
- large wind-turbine main-shaft arrangements
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
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- false brinelling on stopped machines exposed to screen or crusher vibration
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 280 mm bore 23056EMKD1 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.
- Minimum load must be maintained even at rest under vibration: an unloaded 23056EMKD1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- Adapter-sleeve mounting requires the correct sleeve series and locknut for the 280 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K seats.
- Oil relubrication toward 1,200 r/min needs drain and level design; flooding the 106 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 2170 kN rating no longer applies.
- The 2170/3150 kN ratings, 155 kN Pu and 49700 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23056EMKD1 (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 23056EMKD1?
23056EMKD1 is an NTN double-row spherical roller bearing to ISO 15: 280 mm bore, 420 mm OD and 106 mm width (11.024 × 16.535 × 4.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2170 kN, C0 3150 kN, Pu 155 kN, grease limiting speed 960 r/min, oil 1,200 r/min, mass about 49700 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. 23056EMKD1 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 23056EMD1.
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. 23056EMKD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23056EMKD1?
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. 23056EMKD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23056EMKD1 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 2170 kN C / 3150 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.