N334 bearing: complete specifications & equivalents
The N334 is a ISO 15 radial bearing sized 170 x 360 x 72 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 170 mm |
| Outer diameter D | 360 mm |
| Width B | 72 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 885 kN |
| Basic static load rating C0 | 1010 kN |
| Fatigue load limit Pu | 92 kN |
| Limiting speed (mechanical) | 1800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 36100 g |
| Manufacturer designation | NTN N334 |
| 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 & N300-series range
| Bore d | 6.693 in |
|---|---|
| Outer diameter D | 14.173 in |
| Width B | 2.835 in |
| ISO bore code | 34 |
| Radial section height (D−d)/2 | 95 mm |
| Smallest bore in N300-series | 17 mm |
| Largest outer diameter in N300-series | 580 mm |
| Width range across N300-series | 14–108 mm |
| Bore position in N300-series (smallest first) | 26 of 33 |
| Bore above smallest N300-series size | 153 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| N334 | 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 N334 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, N334 appears as a 170 mm bore single-row cylindrical roller bearing (885 kN C / 1010 kN C0) with a pressed sheet-steel cage, listed to the ISO 15 boundary plan. The leading N defines the rib arrangement (inner ring ribbed, outer ring ribless); the dimension-series digits and the two-digit bore code resolve to 170 mm, with 360 mm OD and 72 mm width from the ISO 15 general plan. NTN prints the raceway diameters for this size — Fw 220 mm and Ew 310 mm — the envelope inside the 170/360 mm bore/OD where the rollers actually run. Rating life at 885 kN C assumes clean oil and adequate film; the 92 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. On N arrangements confirm which ring is separable before heating: forcing the ribbed ring off over the roller complement damages the cage and rib faces.
Typical equipment & failure modes
Common applications
- mining SAG/ball-mill drive shafts
- offshore drawworks and winch drums
- heavy press and large gearbox main shafts
- rolling-mill work-roll and backup-roll positions
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- pressed-steel cage pocket wear when rollers skid at light load or too-thin lubricant
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- At 170 mm bore, oil-lubricated arrangements toward 2,200 r/min need positive flow and drain design; the 36100 g N334 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The N rib arrangement is not interchangeable with another prefix on the same 170 mm seat: inner ring ribbed, outer ring ribless. Swapping NU for NJ changes axial location behaviour even though the 360×72 mm envelope matches.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 360 mm race brinells and releases as vibration within hours.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 885/1010 kN pair here belongs to N334 as printed, not to the bare size.
- The N rib arrangement is not interchangeable with another prefix on the same 170 mm seat: inner ring ribbed, outer ring ribless. Swapping NU for NJ changes axial location behaviour even though the 360×72 mm envelope matches.
- The 885/1010 kN ratings, 92 kN Pu and 36100 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for N334 (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 N334?
N334 is an NTN N single-row cylindrical roller bearing to ISO 15: 170 mm bore, 360 mm OD and 72 mm width (6.693 × 14.173 × 2.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 885 kN, C0 1010 kN, Pu 92 kN, grease limiting speed 1,800 r/min, oil 2,200 r/min, mass about 36100 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. N334 is two integral ribs on the inner ring and a ribless separable outer ring — equivalent float behaviour with the separable ring on the housing side.
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. N334 is supplied in the standard open execution shown in the table.
Can N334 take axial load and locate a shaft?
the N design is non-locating like NU but floats with the separable outer ring in the housing. Provide axial location with an adjacent locating bearing (angular-contact, deep-groove or a paired NJ/NUP set).
What do Fw and Ew mean for N334?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 220 mm, Ew 310 mm. The nominal bore/OD remain 170/360 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,800 r/min grease / 2,200 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.