NN4932K bearing: complete specifications & equivalents
The NN4932K is a ISO 15 radial bearing sized 160 x 220 x 60 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 160 mm |
| Outer diameter D | 220 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 395 kN |
| Basic static load rating C0 | 740 kN |
| Fatigue load limit Pu | 74 kN |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5940 g |
| Manufacturer designation | NTN NN4932K |
| 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 & NN4900-series range
| Bore d | 6.299 in |
|---|---|
| Outer diameter D | 8.661 in |
| Width B | 2.362 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in NN4900-series | 100 mm |
| Largest outer diameter in NN4900-series | 440 mm |
| Width range across NN4900-series | 40–118 mm |
| Bore position in NN4900-series (smallest first) | 8 of 18 |
| Bore above smallest NN4900-series size | 60 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NN4932K | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 NN4932K model number is decoded
NTN lists NN4932K on the 160×220 mm envelope, 60 mm wide: a line-contact radial bearing with a machined or stamped steel cage per the precision execution and a grease limiting speed of 2,600 r/min. On the NTN nameplate NN states which ring carries the ribs, which determines whether NN4932K floats or locates; the numeric remainder is the ISO 15 series and 160 mm bore reference, not a fit or clearance instruction. Minimum radial load matters: an unloaded NN4932K at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. The 160 mm (6.299 in) bore and 220 mm (8.661 in) OD are ISO 15 boundary values; fillet and shoulder dimensions must still come from the NTN mounting table for the 60 mm-wide ring. Keep the open bearing wrapped until fitting: the line-contact raceways of the 160 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
Typical equipment & failure modes
Common applications
- high-speed turbine and turbo-blower rotor supports
- coordinate-measuring and semiconductor-equipment drives
- machine-tool main spindles requiring high radial stiffness
- precision gearbox and indexing-drive shafts
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- cage wear accelerated when the EA high-capacity roller complement runs continuously above its thermal balance
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- brinelling from static overload or impact during handling
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
Selection pitfalls — read before you substitute
- At 160 mm bore, oil-lubricated arrangements toward 3,100 r/min need positive flow and drain design; the 5940 g NN4932K ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Open NN4932K units need application-supplied sealing and a defined lubricant schedule; film thickness is the first failure mode for line contact when viscosity drops at the 160 mm contact.
- Grease limiting speed 2,600 r/min and oil 3,100 r/min are different limits for NN4932K: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The NN rib arrangement is not interchangeable with another prefix on the same 160 mm seat: double row, ribbed inner ring, separable outer. Swapping NU for NJ changes axial location behaviour even though the 220×60 mm envelope matches.
- Do not replace NN4932K with a deep-groove ball bearing on rating alone: line contact gives 395 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- The 395/740 kN ratings, 74 kN Pu and 5940 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN4932K (standard execution); other makes sharing the ISO 15 envelope revise internal geometry without changing the order number, so keep the 2203E reference with the specification for critical drives.
Frequently asked questions
What are the dimensions and catalogue data of NN4932K?
NN4932K is an NTN NN double-row precision cylindrical roller bearing to ISO 15: 160 mm bore, 220 mm OD and 60 mm width (6.299 × 8.661 × 2.362 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 395 kN, C0 740 kN, Pu 74 kN, grease limiting speed 2,600 r/min, oil 3,100 r/min, mass about 5940 g. It is open, with a machined or stamped steel cage per the precision execution.
What is the difference between NU, NJ, NUP, N and NF cylindrical roller bearings?
NN and NNU are double-row precision designs rather than single-row rib variants: NN has a ribbed inner ring and separable outer ring, NNU the reverse; both give high radial stiffness for spindles and are commonly ordered with P5/P4 precision and a K 1:12 tapered bore for preload setting. NN4932K is the NN execution.
What do the EA, E and ＊ suffixes mean on NTN cylindrical roller bearings?
EA is NTN's high-capacity design with a pressed sheet-steel cage and optimised roller complement in the same ISO 15 envelope; E marks the high-capacity design at the larger bores; the ＊ symbol printed before the code in the NTN catalogue marks the ULTAGE new-generation specification and is not typed as part of the order number. NN4932K is supplied in the standard open execution shown in the table.
What does the K tapered bore mean on a precision NN bearing like NN4932K?
The K suffix denotes a 1:12 tapered bore. NN4932K mounts on a tapered shaft seat or adapter sleeve and is driven up to a measured residual clearance or preload — this is how precision spindle bearings achieve stiffness without locknut guesswork; the cylindrical-bore NN4932 execution of the same envelope mounts on a plain seat.
What do Fw and Ew mean for NN4932K?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 178.5 mm, Ew 206.5169 mm. The nominal bore/OD remain 160/220 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 2,600 r/min grease / 3,100 r/min oil.
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.