24122EMK30D1 bearing: complete specifications & equivalents
The 24122EMK30D1 is a ISO 15 radial bearing sized 110 x 180 x 69 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 110 mm |
| Outer diameter D | 180 mm |
| Width B | 69 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 622 kN |
| Basic static load rating C0 | 769 kN |
| Fatigue load limit Pu | 35.7 kN |
| Limiting speed (mechanical) | 2200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 6650 g |
| Manufacturer designation | NTN 24122EMK30D1 |
| 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 | 4.331 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 2.717 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 35 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) | 2 of 32 |
| Bore above smallest 24100-series size | 10 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 24122EMD1 | 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 24122EMD1 — 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 24122EMK30D1 model number is decoded
NTN lists 24122EMK30D1 with a 1:30 tapered bore (K30) and D1 outer-ring annular oil groove with holes: 110 mm bore, 180 mm OD, 69 mm width, rated 2,200 r/min on grease. The leading digits are the ISO 15 dimension series (24100 series); the bore code resolves to 110 mm (two-digit code ×5, with the 00–03 exception table), and 180 mm OD / 69 mm width follow the general plan. At 622 kN C and 6650 g mass the 24100 series part is built for shock and vibration; the 69 mm-wide ring needs square abutments to keep both rows equally loaded. The 35.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 69 mm-wide ring seats fully on both sides. Fillet radii on shaft and housing must clear the ring chamfers of the 69 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.
Typical equipment & failure modes
Common applications
- paper-machine dryer and press rolls
- cement-mill and kiln auxiliary drives
- large gearbox and marine gear shafts
- wind-turbine gearbox and rotor bearings
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
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- brinelling from static overload or a hammer blow during sleeve mounting
- false brinelling on stopped machines exposed to screen or crusher vibration
Selection pitfalls — read before you substitute
- Mount the 110 mm ring with induction heat or the sleeve drive-up procedure; at 6650 g cocking damages the spherical raceways, and repositioning after seating is impractical.
- Oil relubrication toward 2,700 r/min needs drain and level design; flooding the 69 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- Never substitute 24122EMK30D1 by envelope alone: the 769 kN C0 and 35.7 kN Pu are specific to the NTN EM machined-brass-cage execution, and vibrating duty depends heavily on cage identity.
- The 1:30 tapered bore is the only difference from the cylindrical-bore 24122EMD1: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 2,200 r/min grease rating is lost to abrasive wear long before fatigue.
- The 622/769 kN ratings, 35.7 kN Pu and 6650 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 24122EMK30D1 (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 24122EMK30D1?
24122EMK30D1 is an NTN double-row spherical roller bearing to ISO 15: 110 mm bore, 180 mm OD and 69 mm width (4.331 × 7.087 × 2.717 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 622 kN, C0 769 kN, Pu 35.7 kN, grease limiting speed 2,200 r/min, oil 2,700 r/min, mass about 6650 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). 24122EMK30D1 mounts on a matching adapter or withdrawal sleeve on a plain 110 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 24122EMD1.
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. 24122EMK30D1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 24122EMK30D1?
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. 24122EMK30D1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 24122EMK30D1 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 — 622 kN C / 769 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.