NA4848 bearing: complete specifications & equivalents
The NA4848 is a ISO 1206 radial bearing sized 240 x 300 x 60 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 240 mm |
| Outer diameter D | 300 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 347 kN |
| Basic static load rating C0 | 1120 kN |
| Fatigue load limit Pu | 112 kN |
| Reference speed (thermal) | 1500 rpm |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9900 g |
| Manufacturer designation | NA 4848 |
| Standard | ISO 1206 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring) · extracted 2026-09-26
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & NA-48-series range
| Bore d | 9.449 in |
|---|---|
| Outer diameter D | 11.811 in |
| Width B | 2.362 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in NA-48-series | 110 mm |
| Largest outer diameter in NA-48-series | 480 mm |
| Width range across NA-48-series | 30–100 mm |
| Bore position in NA-48-series (smallest first) | 12 of 19 |
| Bore above smallest NA-48-series size | 130 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NA4848 model number is decoded
SKF lists NA 4848 in the dimension series 48 needle roller bearings with inner ring with boundary dimensions 240×300×60 mm: an inner ring turns on the shaft while the flanged outer ring carries the needle roller complement in the housing. The designation NA 4848 tells you the envelope — 240×300×60 mm — and the family tells you the construction: complete bearing, replaceable inner ring, flanged outer ring retaining the needle rollers. Execution notes: the inner ring is ground on bore and raceway, so the shaft seat is a normal k5/j6; the flanged outer ring needs no housing shoulder, and NA 49 2RS executions add seals with a wider outer ring. Selection arithmetic: C 347 kN against C0 1120 kN gives a C0/C ratio of 3.23, and the 112 kN fatigue load limit Pu sets the floor for the adjusted-life calculation at contaminated lubrication. Mounting: heat or press the inner ring onto the 240 mm k5 seat (max 120 °C), fit the flanged outer ring into the H7 housing bore, and check the 60 mm assembly for free rotation before applying load.
Typical equipment & failure modes
Common applications
- gearbox shafts where the journal cannot be hardened on site
- wheel and lever pivots needing a replaceable inner ring
- conveyor roller ends and return rollers
- agricultural implement pivots and cutter heads
Known failure patterns
- raceway spalling once the catalogue L10 life is exceeded or after overload events
- cage pocket wear and roller skew after sustained operation with too little radial preload
- grease starvation at the roller ends when relubrication intervals are stretched in dirty duty
- rolling-contact fatigue spalling after the rated L10 life
- inner-ring bore fretting on a loose shaft seat, migrating hard particles into the rolling contact
Selection pitfalls — read before you substitute
- Above 50 mm bore, thermal growth matters: the 240 mm inner ring or journal grows with temperature faster than the housing, and the small clearance of a needle roller contact leaves little reserve — check running clearance hot, not just at assembly.
- Hardness is load capacity: in families without an inner ring the 240 mm journal must hold 58–64 HRC with a ground finish; a surface that looks fine but sits at 45 HRC will rib the raceway within weeks.
- The quoted 347/1120 kN ratings are SKF catalogue values for this exact execution (NA 4848); ratings can be revised without the order number changing, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the drawing.
- The 347/1120 kN ratings and 9900 g mass are SKF catalogue values transcribed from ch. 7.4 of PUB BU/P1 17000 (PDF table page 646); combined-type axial ratings appear in the text above because the structured record carries radial values only.
Frequently asked questions
How is the NA 4848 designation read?
The letters mark a machined-ring needle roller bearing with inner ring: 240 mm bore, 60 mm width, 300 mm OD per the series plan. The hardened inner ring is the raceway, so an ordinary k5 shaft seat suffices.
Can the NA 4848 run on an unhardened shaft?
Yes — that is the point of this family. The NA 4848 carries its own hardened, ground inner ring on a 240 mm seat, so the shaft needs only a normal k5/j6 finish. The inner ring is separable and replaceable.
How should the NA 4848 be mounted?
Mount the inner ring on the 240 mm seat first (induction heat, max 120 °C, or press), then fit the flanged outer ring into the H7 housing bore. Verify free rotation and, for 2RS executions, check the wider outer ring against the housing depth.
What limits the service life of a NA 4848?
Beyond the L10 rating, the practical limits are journal/raceway hardness for the 240 mm seat, lubricant condition at the roller ends, and contamination through open ends — the 30.0 mm radial section leaves no reserve once a raceway is dented or ribboned.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring on 2026-09-26. Read our editorial & correction policy.