22311EMKD1 bearing: complete specifications & equivalents
The 22311EMKD1 is a ISO 15 radial bearing sized 55 x 120 x 43 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 55 mm |
| Outer diameter D | 120 mm |
| Width B | 43 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 296 kN |
| Basic static load rating C0 | 274 kN |
| Fatigue load limit Pu | 17.4 kN |
| Limiting speed (mechanical) | 3900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2290 g |
| Manufacturer designation | NTN 22311EMKD1 |
| 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 & 22300-series range
| Bore d | 2.165 in |
|---|---|
| Outer diameter D | 4.724 in |
| Width B | 1.693 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 32.5 mm |
| Smallest bore in 22300-series | 40 mm |
| Largest outer diameter in 22300-series | 620 mm |
| Width range across 22300-series | 33–185 mm |
| Bore position in 22300-series (smallest first) | 4 of 28 |
| Bore above smallest 22300-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 22311EMD1 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 22300-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 22311EMD1 — 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 22311EMKD1 model number is decoded
22311EMKD1 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 55×120×43 mm to ISO 15, with one-piece machined brass cage (EM high-capacity design). The leading digits are the ISO 15 dimension series (22300 series); the bore code resolves to 55 mm (two-digit code ×5, with the 00–03 exception table), and 120 mm OD / 43 mm width follow the general plan. Two symmetric roller rows share the load: C 296 kN, C0 274 kN (C0/C ≈ 0.93), with useful axial capacity in either direction alongside the dominant radial load. Catalogue mass 2290 g (2.29 kg) for the 55×120×43 mm execution includes the EM machined-brass-cage cage and both roller rows; shaft and housing shoulders must support that ring squarely. Mount 22311EMKD1 on its adapter or withdrawal sleeve on the 55 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
- conveyor pulley and elevator drum shafts
- stone crusher and screen eccentric shafts
- papermaking and printing press rolls
- pump and fan shafts under heavy belt load
Known failure patterns
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- 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
- asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range
- water-induced pitting in washdown or outdoor duty without effective external seals
Selection pitfalls — read before you substitute
- Vibrating-duty 55 mm bearings need the right clearance class and secure fits; verify the k5/m5 seat and relubrication routing rather than assuming the open 22311EMKD1 is greased for life.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 3,900 r/min grease rating is lost to abrasive wear long before fatigue.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 43 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- 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 55 mm bearing, and drive-up procedures differ.
- Adapter-sleeve mounting requires the correct sleeve series and locknut for the 55 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K seats.
- The 296/274 kN ratings, 17.4 kN Pu and 2290 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 22311EMKD1 (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 22311EMKD1?
22311EMKD1 is an NTN double-row spherical roller bearing to ISO 15: 55 mm bore, 120 mm OD and 43 mm width (2.165 × 4.724 × 1.693 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 296 kN, C0 274 kN, Pu 17.4 kN, grease limiting speed 3,900 r/min, oil 4,800 r/min, mass about 2290 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. 22311EMKD1 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 22311EMD1.
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. 22311EMKD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 22311EMKD1?
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. 22311EMKD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 22311EMKD1 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 22300 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 296 kN C / 274 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.