NUP340 bearing: complete specifications & equivalents
The NUP340 is a ISO 15 radial bearing sized 200 x 420 x 80 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 200 mm |
| Outer diameter D | 420 mm |
| Width B | 80 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1080 kN |
| Basic static load rating C0 | 1270 kN |
| Fatigue load limit Pu | 111 kN |
| Limiting speed (mechanical) | 1500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 54500 g |
| Manufacturer designation | NTN NUP340 |
| 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 & NUP300-series range
| Bore d | 7.874 in |
|---|---|
| Outer diameter D | 16.535 in |
| Width B | 3.15 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 110 mm |
| Smallest bore in NUP300-series | 20 mm |
| Largest outer diameter in NUP300-series | 580 mm |
| Width range across NUP300-series | 15–108 mm |
| Bore position in NUP300-series (smallest first) | 28 of 32 |
| Bore above smallest NUP300-series size | 180 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NUP340 | 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 NUP340 model number is decoded
The NTN order number NUP340 denotes a 200×420×80 mm (7.874 × 16.535 × 3.15 in) cylindrical roller bearing in the NUP300 family, a pressed sheet-steel cage. Digit by digit, NUP340 reads as NUP (inner ring two ribs + loose L-ring), ISO 15 series, and bore 200 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. At 1,800 r/min with oil versus 1,500 r/min with grease (a 300 r/min band), lubrication choice for NUP340 is a thermal decision, not just a sealing one. With the inner ring rotating, catalogue practice is a m6/n6 shaft seat and an H7/H6 housing; the outer ring must remain free to creep slightly axially in non-locating NUP arrangements. Keep the open bearing wrapped until fitting: the line-contact raceways of the 200 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
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
- cage distortion after a mounting blow carried through the roller set
- roller-end and raceway scoring from inadequate oil flow under heavy radial load
- hard-particle indentation of raceways in unfiltered oil or open arrangements
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- At 200 mm bore, oil-lubricated arrangements toward 1,800 r/min need positive flow and drain design; the 54500 g NUP340 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The 80 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 200 mm inner ring.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NUP340 skids at 1,500 r/min and fails by smearing long before L10 fatigue.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 1080/1270 kN pair here belongs to NUP340 as printed, not to the bare size.
- Grease limiting speed 1,500 r/min and oil 1,800 r/min are different limits for NUP340: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The 1080/1270 kN ratings, 111 kN Pu and 54500 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NUP340 (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 NUP340?
NUP340 is an NTN NUP single-row cylindrical roller bearing to ISO 15: 200 mm bore, 420 mm OD and 80 mm width (7.874 × 16.535 × 3.15 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1080 kN, C0 1270 kN, Pu 111 kN, grease limiting speed 1,500 r/min, oil 1,800 r/min, mass about 54500 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. NUP340 is the NJ rib arrangement plus a loose L-shaped rib ring on the inner ring — it locates the shaft in both axial directions.
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. NUP340 is supplied in the standard open execution shown in the table.
Can NUP340 take axial load and locate a shaft?
the NUP design provides two-direction axial location via its loose rib ring, for light/moderate thrust guidance. 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 NUP340?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 260 mm, Ew 360 mm. The nominal bore/OD remain 200/420 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,500 r/min grease / 1,800 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.