4306-ATN9 bearing: complete specifications & equivalents

The 4306-ATN9 is a ISO 15 radial bearing sized 30 x 72 x 27 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 72 mm d = 30 B = 27 mm side section front view
Principal dimensions: bore d 30 mm, outer diameter D 72 mm, width B 27 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 30 mm
Outer diameter D 72 mm
Width B 27 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage polymer (PA66 glass-fibre reinforced)
Basic dynamic load rating C 41 kN
Basic static load rating C0 30 kN
Fatigue load limit Pu 1.27 kN
Reference speed (thermal) 16000 rpm
Limiting speed (mechanical) 8500 rpm
Operating temperature -40 to +120 °C
Mass 500 g
Manufacturer designation 4306 ATN9
Standard ISO 15
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018)
Last verified 2026-09-27

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); 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 & 4300-series range

Bore d 1.181 in
Outer diameter D 2.835 in
Width B 1.063 in
ISO bore code 06
Radial section height (D−d)/2 21 mm
Smallest bore in 4300-series 12 mm
Largest outer diameter in 4300-series 160 mm
Width range across 4300-series 17–55 mm
Bore position in 4300-series (smallest first) 6 of 14
Bore above smallest 4300-series size 18 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
62306-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 30×72×27 mm envelope as SKF 62306-2RS1, but catalogue C/C0 differ (41/30 kN vs 28.1/16 kN) — envelope match only after a load check.

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 4306-ATN9 model number is decoded

4306 ATN9 is a double-row deep-groove ball bearing in the 4300-series: the last two digits encode the bore: 4306 carries code 06 = 30 mm (code × 5). Two complete ball sets share the 30×72×27 mm (1.181×2.835×1.063 in) envelope, giving C 41 kN, C0 30 kN and Pu 1.27 kN, with reversing axial capacity a single-row bearing cannot match. ATN9 is the glass-fibre PA66 cage. Limiting speed 8500 r/min, mass 500 g. The arrangement is open and requires external sealing.

Typical equipment & failure modes

Common applications

  • machine tool feed drives
  • lifting and hoisting gear
  • fans with axial thrust reversals
  • industrial wheel arrangements

Known failure patterns

  • uneven load sharing between the two raceways when one ring is tilted
  • polyamide cage embrittlement after sustained high-temperature service
  • fretting corrosion on a creeping shaft or housing seat
  • cage damage from running beyond the limiting speed

Selection pitfalls — read before you substitute

  • Double-row 4306 is open and needs application sealing and lubrication; in dusty drives add external seals rather than expecting the bearing itself to stay clean.
  • C 41 kN in a 27 mm width is the strength of the double-row design; use it for combined or reversing axial loads rather than pure radial duty where a slimmer single-row bearing would run cooler.
  • Fit both rings square on the shoulders: the narrow internal land between the two raceways of 4306-ATN9 is sensitive to cocking during pressing.
  • The ATN9 cage is glass-fibre-reinforced polyamide 66: it is light and quiet but caps continuous service around 100–120 °C in oil/grease — above that use the pressed-steel or machined-cage version of the 30 mm position.
  • The wide 30×72×27 mm envelope is not interchangeable with a single-row 6206 — the housing and shaft shoulders differ, so design the seat for the double-row width from the start.
  • Mount by heating the inner ring (max 120 °C) — driving 4306-ATN9 home through the outer ring or balls brinells the raceways.

Frequently asked questions

What are the dimensions of 4306-ATN9?

Double-row 4306 ATN9 measures 30×72×27 mm (1.181×2.835×1.063 in), about 500 g.

What does ATN9 mean on 4306 ATN9?

A = double-row deep-groove arrangement, TN9 is a glass-fibre-reinforced polyamide 66 cage; it limits continuous temperature to roughly 100–120 °C.

Why choose a double-row 42xx/43xx bearing?

Two ball rows give higher C (41 kN for 4306-ATN9), reversing axial capacity and some moment stiffness in one 27 mm-wide unit — useful on gearbox layshafts and pump shafts.

Is 4306-ATN9 interchangeable with a 62-series single-row bearing?

No: although bore matches, OD and width differ and the seat shoulders must suit the wide double-row ring; 30×72×27 mm is its own envelope.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.