23936EMKD1 bearing: complete specifications & equivalents
The 23936EMKD1 is a ISO 15 radial bearing sized 180 x 250 x 52 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 180 mm |
| Outer diameter D | 250 mm |
| Width B | 52 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass, machined (M1) |
| Basic dynamic load rating C | 573 kN |
| Basic static load rating C0 | 869 kN |
| Fatigue load limit Pu | 57.2 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 7560 g |
| Manufacturer designation | NTN 23936EMKD1 |
| 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 | 7.087 in |
|---|---|
| Outer diameter D | 9.843 in |
| Width B | 2.047 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 35 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) | 3 of 38 |
| Bore above smallest 23900-series size | 20 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23936EMD1 | 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 23936EMD1 — 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 23936EMKD1 model number is decoded
23936EMKD1 is the EM machined-brass-cage execution of NTN's spherical roller range for a 180 mm shaft — 573 kN basic dynamic capacity in a 7560 g, open ISO 15 envelope. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 180 mm (two-digit code ×5, with the 00–03 exception table), and 250 mm OD / 52 mm width follow the general plan. NTN prints two speeds for 23936EMKD1: 1,700 r/min grease and 2,100 r/min oil — the gap of 400 r/min reflects oil cooling of the heavy roller set. Equivalent-load planning keeps a radial plus moderate axial combination on 23936EMKD1; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Never mount 23936EMKD1 by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 250 mm race.
Typical equipment & failure modes
Common applications
- heavy vibrating screens and grizzly feeders
- offshore and marine propulsion shaftlines
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main shafts
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
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 180 mm bore 23936EMKD1 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 23936EMKD1 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- 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 180 mm bearing, and drive-up procedures differ.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a D1 23936EMKD1 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Oil relubrication toward 2,100 r/min needs drain and level design; flooding the 52 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- The 573/869 kN ratings, 57.2 kN Pu and 7560 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23936EMKD1 (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 23936EMKD1?
23936EMKD1 is an NTN double-row spherical roller bearing to ISO 15: 180 mm bore, 250 mm OD and 52 mm width (7.087 × 9.843 × 2.047 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 573 kN, C0 869 kN, Pu 57.2 kN, grease limiting speed 1,700 r/min, oil 2,100 r/min, mass about 7560 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. 23936EMKD1 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 23936EMD1.
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. 23936EMKD1 is the EM machined-brass-cage execution, listed with the ＊ ULTAGE new-generation mark.
What do D1 and W33 mean on 23936EMKD1?
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. 23936EMKD1 carries D1; W33 is the equivalent industry-spelled annular-groove-and-holes feature seen on other executions.
How much misalignment and axial load can 23936EMKD1 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 — 573 kN C / 869 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.