23976EMD1 bearing: complete specifications & equivalents
The 23976EMD1 is a ISO 15 radial bearing sized 380 x 520 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 | 380 mm |
| Outer diameter D | 520 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 | 2340 kN |
| Basic static load rating C0 | 4000 kN |
| Fatigue load limit Pu | 205 kN |
| Limiting speed (mechanical) | 710 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 68000 g |
| Manufacturer designation | NTN 23976EMD1 |
| 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 d | 14.961 in |
|---|---|
| Outer diameter D | 20.472 in |
| Width B | 4.173 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in 23900-series | 160 mm |
| Largest outer diameter in 23900-series | 1820 mm |
| Width range across 23900-series | 45–315 mm |
| Bore position in 23900-series (smallest first) | 14 of 38 |
| Bore above smallest 23900-series size | 220 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23976EMKD1 | 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 23976EMKD1 (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 23976EMD1 model number is decoded
For heavy radial load with misalignment on a 380 mm shaft, NTN supplies 23976EMD1: sphered outer raceway, two roller rows, one-piece machined brass cage (EM high-capacity design), oil speed 910 r/min. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 380 mm (two-digit code ×5, with the 00–03 exception table), and 520 mm OD / 106 mm width follow the general plan. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the EM machined-brass-cage cage. Catalogue mass 68000 g (68.00 kg) for the 380×520×106 mm execution includes the EM machined-brass-cage cage and both roller rows; shaft and housing shoulders must support that ring squarely. 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
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
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 380 mm bore 23976EMD1 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.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 710 r/min grease rating is lost to abrasive wear long before fatigue.
- The cylindrical-bore 23976EMD1 and its tapered-bore counterpart 23976EMKD1 share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
- Minimum load must be maintained even at rest under vibration: an unloaded 23976EMD1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- Never substitute 23976EMD1 by envelope alone: the 4000 kN C0 and 205 kN Pu are specific to the NTN EM machined-brass-cage execution, and vibrating duty depends heavily on cage identity.
- The 2340/4000 kN ratings, 205 kN Pu and 68000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23976EMD1 (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 23976EMD1?
23976EMD1 is an NTN double-row spherical roller bearing to ISO 15: 380 mm bore, 520 mm OD and 106 mm width (14.961 × 20.472 × 4.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2340 kN, C0 4000 kN, Pu 205 kN, grease limiting speed 710 r/min, oil 910 r/min, mass about 68000 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?
23976EMD1 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 23976EMKD1 (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. 23976EMD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23976EMD1?
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. 23976EMD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23976EMD1 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 — 2340 kN C / 4000 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.