NF336 bearing: complete specifications & equivalents
The NF336 is a ISO 15 radial bearing sized 180 x 380 x 75 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 180 mm |
| Outer diameter D | 380 mm |
| Width B | 75 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1000 kN |
| Basic static load rating C0 | 1150 kN |
| Fatigue load limit Pu | 103 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 43200 g |
| Manufacturer designation | NTN NF336 |
| 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 & NF300-series range
| Bore d | 7.087 in |
|---|---|
| Outer diameter D | 14.961 in |
| Width B | 2.953 in |
| ISO bore code | 36 |
| Radial section height (D−d)/2 | 100 mm |
| Smallest bore in NF300-series | 20 mm |
| Largest outer diameter in NF300-series | 580 mm |
| Width range across NF300-series | 15–108 mm |
| Bore position in NF300-series (smallest first) | 26 of 32 |
| Bore above smallest NF300-series size | 160 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF336 | 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 NF336 model number is decoded
NF336 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 1000 kN dynamic rating in the 180 mm bore. Digit by digit, NF336 reads as NF (one rib on each ring), ISO 15 series, and bore 180 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. With C 1000 kN and C0 1150 kN (C0/C ≈ 1.15) the bearing is proportioned for heavy radial load; the NF design gives one-direction axial guidance via its single outer-ring rib. Equivalent-load planning treats NF336 as a pure radial bearing: keep P below 1000 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 180 mm shaft.
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
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
- electrical pitting on VFD-driven motor shafts without grounding protection
Selection pitfalls — read before you substitute
- At 180 mm bore, oil-lubricated arrangements toward 2,000 r/min need positive flow and drain design; the 43200 g NF336 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The 100.0 mm section at 180 mm bore leaves a narrow oil path; with the standard cage the relubrication groove and oil-level design must keep grease from churning in the 75 mm-wide cavity.
- If the shaft must be located both ways, do not use NF336 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- The 75 mm width and abutment faces must be square to the axis; a tilted spacer concentrates load across the roller set and shows as uneven raceway polish on the 180 mm inner ring.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF336 skids at 1,700 r/min and fails by smearing long before L10 fatigue.
- The 1000/1150 kN ratings, 103 kN Pu and 43200 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF336 (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 NF336?
NF336 is an NTN NF single-row cylindrical roller bearing to ISO 15: 180 mm bore, 380 mm OD and 75 mm width (7.087 × 14.961 × 2.953 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1000 kN, C0 1150 kN, Pu 103 kN, grease limiting speed 1,700 r/min, oil 2,000 r/min, mass about 43200 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. NF336 is one integral rib on each ring — separable inner ring with single-direction axial guidance and a defined shaft position.
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. NF336 is supplied in the standard open execution shown in the table.
Can NF336 take axial load and locate a shaft?
the NF design gives one-direction axial guidance via its single outer-ring rib. The loose rib ring still only suits light/short-duration axial guidance; heavy thrust belongs to a dedicated thrust bearing.
What do Fw and Ew mean for NF336?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 232 mm, Ew 328 mm. The nominal bore/OD remain 180/380 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,700 r/min grease / 2,000 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.