23084BK bearing: complete specifications & equivalents
The 23084BK is a ISO 15 radial bearing sized 420 x 620 x 150 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 420 mm |
| Outer diameter D | 620 mm |
| Width B | 150 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 3450 kN |
| Basic static load rating C0 | 6400 kN |
| Fatigue load limit Pu | 475 kN |
| Limiting speed (mechanical) | 490 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 152000 g |
| Manufacturer designation | NTN 23084BK |
| 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 & 23000-series range
| Bore d | 16.535 in |
|---|---|
| Outer diameter D | 24.409 in |
| Width B | 5.906 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 100 mm |
| Smallest bore in 23000-series | 70 mm |
| Largest outer diameter in 23000-series | 1580 mm |
| Width range across 23000-series | 27–345 mm |
| Bore position in 23000-series (smallest first) | 28 of 46 |
| Bore above smallest 23000-series size | 350 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23084B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23084B — 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 23084BK model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 23084BK denotes the 420 mm bore spherical roller bearing (3450 kN C / 6400 kN C0) in the 23000 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 420 mm (two-digit code ×5, with the 00–03 exception table), and 620 mm OD / 150 mm width follow the general plan. The 100.0 mm radial section over the 420 mm bore carries two roller rows; capacity per millimetre of bore is about 8.2 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. The 100.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 150 mm-wide ring seats fully on both sides. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 420 mm bore assembly by hand to distribute it across both rows.
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
- 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
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- At 420 mm bore 23084BK 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.
- Do not confuse EA and EM at the same number: 23084BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 420×620 mm envelope is identical.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 150 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 490 r/min grease rating is lost to abrasive wear long before fatigue.
- The 1:12 tapered bore is the only difference from the cylindrical-bore 23084B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- The 3450/6400 kN ratings, 475 kN Pu and 152000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23084BK (basic); 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 23084BK?
23084BK is an NTN double-row spherical roller bearing to ISO 15: 420 mm bore, 620 mm OD and 150 mm width (16.535 × 24.409 × 5.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 3450 kN, C0 6400 kN, Pu 475 kN, grease limiting speed 490 r/min, oil 640 r/min, mass about 152000 g. It is open, with pressed-steel cage (standard execution) 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. 23084BK 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 23084B.
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. 23084BK is the basic execution.
What do D1 and W33 mean on 23084BK?
23084BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope.
How much misalignment and axial load can 23084BK take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 3450 kN C / 6400 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.