23948EMKD1 bearing: complete specifications & equivalents
The 23948EMKD1 is a ISO 15 radial bearing sized 240 x 320 x 60 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 240 mm |
| Outer diameter D | 320 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 815 kN |
| Basic static load rating C0 | 1350 kN |
| Fatigue load limit Pu | 87.7 kN |
| Limiting speed (mechanical) | 1300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 13100 g |
| Manufacturer designation | NTN 23948EMKD1 |
| 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 | 9.449 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 2.362 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 40 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) | 7 of 38 |
| Bore above smallest 23900-series size | 80 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23948EMD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23948EMD1 — 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 23948EMKD1 model number is decoded
NTN lists 23948EMKD1 with a 1:12 tapered bore (K) and D1 outer-ring annular oil groove with holes: 240 mm bore, 320 mm OD, 60 mm width, rated 1,300 r/min on grease. Reading the full code: the number gives the 240×320 mm envelope, EM names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and D1 outer-ring annular oil groove with holes completes the order number. NTN prints two speeds for 23948EMKD1: 1,300 r/min grease and 1,600 r/min oil — the gap of 300 r/min reflects oil cooling of the heavy roller set. Equivalent-load planning keeps a radial plus moderate axial combination on 23948EMKD1; 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 240 mm bore assembly by hand to distribute it across both rows.
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
- raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
- 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
- false brinelling on stopped machines exposed to screen or crusher vibration
- hard-particle indentation through the open arrangement in dusty mining duty
Selection pitfalls — read before you substitute
- At 240 mm bore 23948EMKD1 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.
- Oil relubrication toward 1,600 r/min needs drain and level design; flooding the 60 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- 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 240 mm bearing, and drive-up procedures differ.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 23948EMKD1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Oil relubrication toward 1,600 r/min needs drain and level design; flooding the 60 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- The 815/1350 kN ratings, 87.7 kN Pu and 13100 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23948EMKD1 (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 23948EMKD1?
23948EMKD1 is an NTN double-row spherical roller bearing to ISO 15: 240 mm bore, 320 mm OD and 60 mm width (9.449 × 12.598 × 2.362 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 815 kN, C0 1350 kN, Pu 87.7 kN, grease limiting speed 1,300 r/min, oil 1,600 r/min, mass about 13100 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. 23948EMKD1 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 23948EMD1.
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. 23948EMKD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23948EMKD1?
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. 23948EMKD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23948EMKD1 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 — 815 kN C / 1350 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.