6068-M bearing: complete specifications & equivalents

The 6068-M is a ISO 15 radial bearing sized 340 x 520 x 82 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 = 520 mm d = 340 B = 82 mm side section front view
Principal dimensions: bore d 340 mm, outer diameter D 520 mm, width B 82 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 340 mm
Outer diameter D 520 mm
Width B 82 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage brass
Basic dynamic load rating C 423 kN
Basic static load rating C0 640 kN
Fatigue load limit Pu 13.2 kN
Reference speed (thermal) 2400 rpm
Limiting speed (mechanical) 2200 rpm
Operating temperature -40 to +120 °C
Mass 62000 g
Manufacturer designation 6068 M
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 & 6000-series range

Bore d 13.386 in
Outer diameter D 20.472 in
Width B 3.228 in
ISO bore code 68
Radial section height (D−d)/2 90 mm
Smallest bore in 6000-series 4 mm
Largest outer diameter in 6000-series 1150 mm
Width range across 6000-series 4–155 mm
Bore position in 6000-series (smallest first) 45 of 61
Bore above smallest 6000-series size 336 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6068 NTN full
Dimensions and internal design equivalent — standard interchange.
NTN counterpart NTN 6068 on the same 340×520×82 mm envelope with ratings within 10 % — interchange after checking seal, cage and precision details on both pages.

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 6068-M model number is decoded

In the 6000-series, the last two digits encode the bore: 6068 carries code 68 = 340 mm (code × 5). The envelope is 340×520×82 mm (13.386×20.472×3.228 in) with a 90.0 mm radial section height, C 423 kN, C0 640 kN and Pu 13.2 kN. The open 6068 M carries no shields or seals and relies on application lubrication and external sealing. The M suffix identifies the machined brass cage execution, a separate order number from the pressed-steel version. Limiting speed 2200 r/min, catalogue mass 62000 g.

Typical equipment & failure modes

Common applications

  • hoists and winches
  • industrial fans and blowers
  • mill and kiln auxiliaries
  • pulp and paper machinery

Known failure patterns

  • contamination wear when the open arrangement is used without external seals
  • lubricant starvation where no regreasing interval is maintained
  • brinelling from static overload or hammer blows during mounting
  • false brinelling from vibration while the shaft stands idle

Selection pitfalls — read before you substitute

  • Fillet radii must clear the 6068-M chamfer so the 82 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
  • Catalogue ratings for 6068-M (C 423 kN, C0 640 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
  • The M suffix on 6068-M denotes a machined brass cage: it is the choice for high speeds, marginal lubrication and shock/vibration duty, and it is temperature-tolerant where polymer cages are not — the 62000 g quoted mass includes the heavier cage.
  • Open 6068-M needs external sealing at the arrangement level; in dusty housings its life depends entirely on those external seals and the regreasing schedule.
  • Plan a relubrication interval for 6068-M; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
  • Assign interference to the rotating ring: on a conventional shaft-mounted 340 mm position the inner ring rotates, so use a k5/m6 shaft seat with an H7 housing — reverse the logic if the outer ring rotates.

Frequently asked questions

What are the dimensions of 6068-M?

The SKF 6068 M measures 340 mm bore × 520 mm OD × 82 mm width (13.386 × 20.472 × 3.228 in), mass about 62000 g. It is open, with no shields or seals.

How does the bore code in 6068 work?

The final two digits of 6068 are bore code 68, multiplied by 5 to give 340 mm.

What is the difference between 6068-M and a same-bore 62-series bearing?

Section height differs: 6068-M has a 90 mm radial section and C 423 kN; always match d, D and B — same bore alone never makes two bearings interchangeable.

Which fits should I use for 6068-M?

With a rotating inner ring use roughly m6 on the shaft and H7 in the 520 mm housing; reverse the interference if the outer ring rotates.

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.