23984EMD1 bearing: complete specifications & equivalents

The 23984EMD1 is a ISO 15 radial bearing sized 420 x 560 x 106 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 = 560 mm d = 420 B = 106 mm side section front view
Principal dimensions: bore d 420 mm, outer diameter D 560 mm, width B 106 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 420 mm
Outer diameter D 560 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 2390 kN
Basic static load rating C0 4320 kN
Fatigue load limit Pu 230 kN
Limiting speed (mechanical) 650 rpm
Operating temperature -40 to +120 °C
Mass 74900 g
Manufacturer designation NTN 23984EMD1
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 & 23900-series range

Bore d16.535 in
Outer diameter D22.047 in
Width B4.173 in
ISO bore code—
Radial section height (D−d)/270 mm
Smallest bore in 23900-series160 mm
Largest outer diameter in 23900-series1820 mm
Width range across 23900-series45–315 mm
Bore position in 23900-series (smallest first)16 of 38
Bore above smallest 23900-series size260 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
23984EMKD1 NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 23984EMKD1 (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 23984EMD1 model number is decoded

NTN lists 23984EMD1 with a cylindrical bore and D1 outer-ring annular oil groove with holes: 420 mm bore, 560 mm OD, 106 mm width, rated 650 r/min on grease. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 420 mm (two-digit code ×5, with the 00–03 exception table), and 560 mm OD / 106 mm width follow the general plan. The 70.0 mm radial section over the 420 mm bore carries two roller rows; capacity per millimetre of bore is about 5.7 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. Catalogue mass 74900 g (74.90 kg) for the 420×560×106 mm execution includes the EM machined-brass-cage cage and both roller rows; shaft and housing shoulders must support that ring squarely. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 23984EMD1 leaves sealing and the C3/C4 clearance decision to the application drawing.

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

  • raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
  • pressed EA cage fatigue under sustained vibration when minimum load is not maintained
  • sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
  • hard-particle indentation through the open arrangement in dusty mining duty
  • brinelling from static overload or a hammer blow during sleeve mounting

Selection pitfalls — read before you substitute

  • At 420 mm bore 23984EMD1 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 23984EMD1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
  • Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 650 r/min grease rating is lost to abrasive wear long before fatigue.
  • Minimum load must be maintained even at rest under vibration: an unloaded 23984EMD1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
  • The cylindrical-bore 23984EMD1 and its tapered-bore counterpart 23984EMKD1 share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
  • The 2390/4320 kN ratings, 230 kN Pu and 74900 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23984EMD1 (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 23984EMD1?

23984EMD1 is an NTN double-row spherical roller bearing to ISO 15: 420 mm bore, 560 mm OD and 106 mm width (16.535 × 22.047 × 4.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2390 kN, C0 4320 kN, Pu 230 kN, grease limiting speed 650 r/min, oil 830 r/min, mass about 74900 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?

23984EMD1 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 23984EMKD1 (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. 23984EMD1 is the EM machined-brass-cage execution, listed with the * ULTAGE new-generation mark.

What do D1 and W33 mean on 23984EMD1?

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. 23984EMD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.

How much misalignment and axial load can 23984EMD1 take?

The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 2390 kN C / 4320 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.