NN3020 bearing: complete specifications & equivalents
The NN3020 is a ISO 15 radial bearing sized 100 x 150 x 37 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 100 mm |
| Outer diameter D | 150 mm |
| Width B | 37 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 170 kN |
| Basic static load rating C0 | 256 kN |
| Fatigue load limit Pu | 29.2 kN |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2260 g |
| Manufacturer designation | NTN NN3020 |
| 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 & NN3000-series range
| Bore d | 3.937 in |
|---|---|
| Outer diameter D | 5.906 in |
| Width B | 1.457 in |
| ISO bore code | 20 |
| Radial section height (D−d)/2 | 25 mm |
| Smallest bore in NN3000-series | 25 mm |
| Largest outer diameter in NN3000-series | 680 mm |
| Width range across NN3000-series | 16–163 mm |
| Bore position in NN3000-series (smallest first) | 16 of 40 |
| Bore above smallest NN3000-series size | 75 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NN3020 | 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 NN3020 model number is decoded
NN3020 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 170 kN dynamic rating in the 100 mm bore. Digit by digit, NN3020 reads as NN (double row, ribbed inner ring, separable outer), ISO 15 series, and bore 100 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. At 4,800 r/min with oil versus 4,000 r/min with grease (a 800 r/min band), lubrication choice for NN3020 is a thermal decision, not just a sealing one. With the inner ring rotating, catalogue practice is a k5/m5 shaft seat and an H7/H6 housing; the outer ring must remain free to creep slightly axially in non-locating NN arrangements. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 100 mm shaft.
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
- 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
- Induction-heat the 100 mm inner ring (max 120 °C) and mount it before fitting the outer ring; the ring mass makes square guidance essential — driving through the rollers brinells the 150 mm raceway.
- The NN rib arrangement is not interchangeable with another prefix on the same 100 mm seat: double row, ribbed inner ring, separable outer. Swapping NU for NJ changes axial location behaviour even though the 150×37 mm envelope matches.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 150 mm race brinells and releases as vibration within hours.
- Do not replace NN3020 with a deep-groove ball bearing on rating alone: line contact gives 170 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- Grease limiting speed 4,000 r/min and oil 4,800 r/min are different limits for NN3020: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The 170/256 kN ratings, 29.2 kN Pu and 2260 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN3020 (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 NN3020?
NN3020 is an NTN NN double-row precision cylindrical roller bearing to ISO 15: 100 mm bore, 150 mm OD and 37 mm width (3.937 × 5.906 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 170 kN, C0 256 kN, Pu 29.2 kN, grease limiting speed 4,000 r/min, oil 4,800 r/min, mass about 2260 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. NN3020 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. NN3020 is supplied in the standard open execution shown in the table.
What does the K tapered bore mean on a precision NN bearing like NN3020?
NN3020 has a cylindrical bore and mounts on a plain machined shaft seat; a K execution (1:12 taper) exists in the NN3000 series when preload must be set by drive-up on a tapered seat.
What speeds and lubrication apply to NN3020?
NTN rates NN3020 at 4,000 r/min with grease and 4,800 r/min with oil. The grease figure is the cage/film mechanical ceiling; the oil figure assumes circulating or carefully supplied oil that removes heat from the line-contact zone.
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.