24138EMK30D1 bearing: complete specifications & equivalents
The 24138EMK30D1 is a ISO 15 radial bearing sized 190 x 320 x 128 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 190 mm |
| Outer diameter D | 320 mm |
| Width B | 128 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 1900 kN |
| Basic static load rating C0 | 2700 kN |
| Fatigue load limit Pu | 96.8 kN |
| Limiting speed (mechanical) | 1200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 41500 g |
| Manufacturer designation | NTN 24138EMK30D1 |
| 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 & 24100-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 5.039 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 65 mm |
| Smallest bore in 24100-series | 100 mm |
| Largest outer diameter in 24100-series | 1150 mm |
| Width range across 24100-series | 65–438 mm |
| Bore position in 24100-series (smallest first) | 10 of 32 |
| Bore above smallest 24100-series size | 90 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 24138EMD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24100-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 24138EMD1 — 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 24138EMK30D1 model number is decoded
NTN lists 24138EMK30D1 with a 1:30 tapered bore (K30) and D1 outer-ring annular oil groove with holes: 190 mm bore, 320 mm OD, 128 mm width, rated 1,200 r/min on grease. Reading the full code: the number gives the 190×320 mm envelope, EM names the cage/capacity execution, K30 marks the 1:30 tapered bore for sleeve mounting, and D1 outer-ring annular oil groove with holes completes the order number. Pu 96.8 kN is the catalogue fatigue load limit for 24138EMK30D1, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. The 65.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 128 mm-wide ring seats fully on both sides. Mount 24138EMK30D1 on its adapter or withdrawal sleeve on the 190 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
- 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
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- 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
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
- false brinelling on stopped machines exposed to screen or crusher vibration
Selection pitfalls — read before you substitute
- At 190 mm bore 24138EMK30D1 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 24138EMK30D1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 24138EMK30D1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Adapter-sleeve mounting requires the correct sleeve series and locknut for the 190 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K seats.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 24138EMK30D1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 1900/2700 kN ratings, 96.8 kN Pu and 41500 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 24138EMK30D1 (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 24138EMK30D1?
24138EMK30D1 is an NTN double-row spherical roller bearing to ISO 15: 190 mm bore, 320 mm OD and 128 mm width (7.48 × 12.598 × 5.039 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1900 kN, C0 2700 kN, Pu 96.8 kN, grease limiting speed 1,200 r/min, oil 1,500 r/min, mass about 41500 g. It is open, with one-piece machined brass cage (EM high-capacity design) and a 1:30 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K30 denotes a 1:30 tapered bore (the wide 24100 series). 24138EMK30D1 mounts on a matching adapter or withdrawal sleeve on a plain 190 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 24138EMD1.
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. 24138EMK30D1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 24138EMK30D1?
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. 24138EMK30D1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 24138EMK30D1 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 1900 kN C / 2700 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.