6068 bearing: complete specifications & equivalents
The 6068 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.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| 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 | steel |
| Basic dynamic load rating C | 465 kN |
| Basic static load rating C0 | 610 kN |
| Fatigue load limit Pu | 21.9 kN |
| Limiting speed (mechanical) | 1100 rpm |
| Mass | 61800 g |
| Manufacturer designation | NTN 6068 |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) |
| Last verified | 2026-09-25 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); 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 & 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 | 10 mm |
| Largest outer diameter in 6000-series | 620 mm |
| Width range across 6000-series | 8–90 mm |
| Bore position in 6000-series (smallest first) | 39 of 43 |
| Bore above smallest 6000-series size | 330 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6068 | ISO-INTERCHANGE | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension interchange; ratings above are NTN 2203-3/E values and differ by brand — verify per supplier. |
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 model number is decoded
In the 6000-series (diameter series 0 of ISO 15) the last two digits encode the bore: 6068 carries bore code 68 = 340 mm. Outside diameter 520 mm and width 82 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 340 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. In the NTN catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal).
Typical equipment & failure modes
Common applications
- industrial fans and blowers
- hoists and winches
- heavy conveyors
- pulp and paper machinery
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- cage damage from operation beyond the limiting speed
- electrical pitting in VFD-driven motors without grounding protection
Selection pitfalls — read before you substitute
- Mount this 340 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
- The 60xx extra-light section at 340 mm bore uses a smaller 520 mm OD than a 6268; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
- The open 6068 has no lubricant retention: grease escapes and contaminants migrate straight into the 340×520×82 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 6000-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6068 units.
- Deep-groove ball bearings tolerate only minutes of misalignment; if the 520 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 6068.
- The open 6068 has no integral sealing; in the NTN 2203 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), LLB/LLF (non-contact rubber seals), LLU (contact rubber seals) and LLH (a low-torque contact seal with higher speed capability than LLU). A JR or JRX suffix (as printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
- The 465/610 kN load ratings, 21.9 kN fatigue load limit Cu and 61800 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6068; this seal/size combination has no counterpart from another catalogue on this site, so the page rests on a single manufacturer source — internal geometry and ratings legitimately differ between brands, so re-verify before substituting in a rated drive.
Frequently asked questions
What are the dimensions of a 6068 bearing?
A 6068 deep-groove ball bearing has a 340 mm bore, 520 mm outer diameter and 82 mm width (13.386 × 20.472 × 3.228 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How does the 6068 bore code work?
The last two digits of 6068 are bore code 68, giving 68 × 5 = 340 mm bore. The 520 mm outside diameter and 82 mm width follow the ISO 15 diameter series, not the bore code alone.
What does no suffix on 6068 mean?
A bare 6068 designation means open: no shields or seals, normal CN radial clearance and P0 normal tolerance unless further suffixes are ordered. The application must supply and retain the lubrication.
How does the 6000 compare with other series at the same 340 mm bore?
The second digit is the diameter series: 60 is the smallest standard section (520×82 mm, 90.0 mm radial section) at 340 mm bore — below 62/63/64 in load capacity, for light loads in compact spaces.
What is the NTN designation and catalogue data for 6068?
In the NTN Ball and Roller Bearings catalogue (CAT.No.2203-3/E, 2024) this size is listed as 6068 — the open (unsealed) execution, 340×520×82 mm per ISO 15. Quoted values: C 465 kN, C0 610 kN, Cu 21.9 kN, mass 61800 g. Grease limiting speed 1100 rpm. The industry-neutral page spelling 6068 follows the seal-suffix convention used across this site, not NTN order-number spelling.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) on 2026-09-25. Read our editorial & correction policy.