21314-NTN bearing: complete specifications & equivalents
The 21314-NTN is a ISO 15 radial bearing sized 70 x 150 x 35 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 70 mm |
| Outer diameter D | 150 mm |
| Width B | 35 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 245 kN |
| Basic static load rating C0 | 262 kN |
| Fatigue load limit Pu | 33.5 kN |
| Limiting speed (mechanical) | 2900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3180 g |
| Manufacturer designation | NTN 21314 |
| 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 & 21300-series range
| Bore d | 2.756 in |
|---|---|
| Outer diameter D | 5.906 in |
| Width B | 1.378 in |
| ISO bore code | 14 |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 21300-series | 40 mm |
| Largest outer diameter in 21300-series | 240 mm |
| Width range across 21300-series | 23–50 mm |
| Bore position in 21300-series (smallest first) | 7 of 14 |
| Bore above smallest 21300-series size | 30 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 21314K | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 21300-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 21314K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement. |
| 21314 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 70×150×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 21314-EK | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 70×150×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 21314-NTN model number is decoded
21314 is the C design-code execution of NTN's spherical roller range for a 70 mm shaft — 245 kN basic dynamic capacity in a 3180 g, open ISO 15 envelope. Reading the full code: the number gives the 70×150 mm envelope, C/CK names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. Suffix reading on 21314: C is the cage/design code for the NTN 213 series, CK adding the tapered bore; quote the full code because each suffix is a distinct article. 70 mm bore is 2.756 in and 150 mm OD is 5.906 in; the ISO 15 envelope swaps between brands, but the 245/262 kN ratings and cage design are NTN 2203E values. Fillet radii on shaft and housing must clear the ring chamfers of the 35 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.
Typical equipment & failure modes
Common applications
- cement-mill and kiln auxiliary drives
- large gearbox and marine gear shafts
- wind-turbine gearbox and rotor bearings
- large vibrating screens and mining feeders
Known failure patterns
- raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
- cage damage when a mounting force is applied through the roller set instead of the ring face
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- false brinelling on stopped machines exposed to screen or crusher vibration
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- Mount the 70 mm ring with induction heat or the sleeve drive-up procedure; at 3180 g cocking damages the spherical raceways, and repositioning after seating is impractical.
- Never substitute 21314 by envelope alone: the 262 kN C0 and 33.5 kN Pu are specific to the NTN C design-code execution, and vibrating duty depends heavily on cage identity.
- Minimum load must be maintained even at rest under vibration: an unloaded 21314 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 35 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 35 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The 245/262 kN ratings, 33.5 kN Pu and 3180 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 21314 (C design-code); 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 21314?
21314 is an NTN double-row spherical roller bearing to ISO 15: 70 mm bore, 150 mm OD and 35 mm width (2.756 × 5.906 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 245 kN, C0 262 kN, Pu 33.5 kN, grease limiting speed 2,900 r/min, oil 3,800 r/min, mass about 3180 g. It is open, with pressed-steel cage of the 213-series C design.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
21314 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 21314K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting.
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. 21314 is the C design-code execution.
What do D1 and W33 mean on 21314?
21314 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 21314 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 21300 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 245 kN C / 262 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.