NJ406 bearing: complete specifications & equivalents
The NJ406 is a ISO 15 radial bearing sized 30 x 90 x 23 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 30 mm |
| Outer diameter D | 90 mm |
| Width B | 23 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 69.5 kN |
| Basic static load rating C0 | 55 kN |
| Fatigue load limit Pu | 6.7 kN |
| Limiting speed (mechanical) | 7300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 732 g |
| Manufacturer designation | NTN NJ406 |
| 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 & NJ400-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 3.543 in |
| Width B | 0.906 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in NJ400-series | 25 mm |
| Largest outer diameter in NJ400-series | 280 mm |
| Width range across NJ400-series | 21–65 mm |
| Bore position in NJ400-series (smallest first) | 2 of 13 |
| Bore above smallest NJ400-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ406-MA | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 30×90×23 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 NJ406 model number is decoded
The NTN order number NJ406 denotes a 30×90×23 mm (1.181 × 3.543 × 0.906 in) cylindrical roller bearing in the NJ400 family, a pressed sheet-steel cage. Digit by digit, NJ406 reads as NJ (inner ring two ribs + one outer rib), ISO 15 series, and bore 30 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. The 23 mm width and 30.0 mm section put the NJ400 series in the heavy (04) section; wide 22/23 variants at the same bore change OD, width and heat generation and are not drop-in swaps. The 30 mm (1.181 in) bore and 90 mm (3.543 in) OD are ISO 15 boundary values; fillet and shoulder dimensions must still come from the NTN mounting table for the 23 mm-wide ring. Mount the separable inner ring + roller assembly on the shaft first and slide the outer ring into the housing; never press the outer ring through the rollers of NJ406.
Typical equipment & failure modes
Common applications
- material-handling drum and wheel shafts
- papermaking and printing auxiliary drives
- fan and blower rotor positions
- industrial gearbox input and output 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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- fretting corrosion on a loose rotating shaft seat
- electrical pitting on VFD-driven motor shafts without grounding protection
Selection pitfalls — read before you substitute
- On this 30 mm bore, shaft thermal growth can preload the inner ring if the fit is too tight; verify residual interference at temperature and confirm the float ring still slides after mounting NJ406.
- The NJ rib arrangement is not interchangeable with another prefix on the same 30 mm seat: inner ring two ribs + one outer rib. Swapping NU for NJ changes axial location behaviour even though the 90×23 mm envelope matches.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 69.5/55 kN pair here belongs to NJ406 as printed, not to the bare size.
- Do not replace NJ406 with a deep-groove ball bearing on rating alone: line contact gives 69.5 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- Open NJ406 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 30 mm contact.
- The 69.5/55 kN ratings, 6.7 kN Pu and 732 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ406 (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 NJ406?
NJ406 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 30 mm bore, 90 mm OD and 23 mm width (1.181 × 3.543 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69.5 kN, C0 55 kN, Pu 6.7 kN, grease limiting speed 7,300 r/min, oil 8,500 r/min, mass about 732 g. It is open, with a pressed sheet-steel cage.
What is the difference between NU, NJ, NUP, N and NF cylindrical roller bearings?
The prefix states the rib arrangement: NU has two outer-ring ribs and a ribless inner ring (float, no axial load); NJ adds ribs for one-direction location; NUP adds a loose L-ring to locate both directions; N has two inner-ring ribs and a separable outer ring; NF has one rib per ring for one-direction guidance. NJ406 is two integral ribs on the inner ring and one rib on the outer ring — it locates the shaft in one axial direction.
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. NJ406 is supplied in the standard open execution shown in the table.
Can NJ406 take axial load and locate a shaft?
the NJ design accepts axial load in one direction and provides one-way shaft location. For two-direction location use an NUP execution or an NJ pair with loose rib rings.
What do Fw and Ew mean for NJ406?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 45 mm, Ew 73 mm. The nominal bore/OD remain 30/90 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 7,300 r/min grease / 8,500 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.