6040 bearing: complete specifications & equivalents
The 6040 is a ISO 15 radial bearing sized 200 x 310 x 51 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NSK |
| Bore diameter d | 200 mm |
| Outer diameter D | 310 mm |
| Width B | 51 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 228 kN |
| Basic static load rating C0 | 226 kN |
| Mass | 12000 g |
| Manufacturer designation | NSK 6040 |
| Standard | ISO 15 |
| Catalog version | NSK Rolling Bearings E1103 Part C |
| Last verified | 2026-09-24 |
Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24
Dimensions in inches & 6000-series range
| Bore d | 7.874 in |
|---|---|
| Outer diameter D | 12.205 in |
| Width B | 2.008 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 55 mm |
| Smallest bore in 6000-series | 10 mm |
| Largest outer diameter in 6000-series | 420 mm |
| Width range across 6000-series | 8–65 mm |
| Bore position in 6000-series (smallest first) | 32 of 36 |
| Bore above smallest 6000-series size | 190 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6040 | ISO-INTERCHANGE | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension interchange; ratings above are NSK E1103 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 6040 model number is decoded
In the 6000-series (ISO 15 diameter series 0) the last two digits encode the bore: 6040 carries bore code 40 = 200 mm. Outside diameter 310 mm and width 51 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 200 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- heavy conveyors
- pulp and paper machinery
- medium and heavy industrial drives
- large gearboxes
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- rolling-contact fatigue spalling after the rated L10 life is exceeded
- brinelling from static overload or hammering during mounting
Selection pitfalls — read before you substitute
- Mount this 200 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 200 mm bore uses a smaller 310 mm OD than a 6240; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
- The open 6040 has no lubricant retention: grease escapes and contaminants migrate straight into the 200×310×51 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 6040 units.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 6040-C3. No clearance suffix means normal CN clearance.
- The open 6040 needs external sealing and application-supplied lubrication; in the NSK catalogue the protected variants are separate order numbers with suffixes ZZ (shields), VV (non-contact rubber seals) and DDU (contact rubber seals).
- The 228/226 kN ratings, mass 12000 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6040; this seal/size combination has no counterpart in the SKF 17000 extract used elsewhere 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 6040 bearing?
A 6040 deep-groove ball bearing has a 200 mm bore, 310 mm outer diameter and 51 mm width (7.874 × 12.205 × 2.008 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How does the 6040 bore code work?
The last two digits of 6040 are bore code 40, giving 40 × 5 = 200 mm bore. The 310 mm outside diameter and 51 mm width follow the ISO 15 diameter series, not the bore code alone.
What does no suffix on 6040 mean?
A bare 6040 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 200 mm bore?
The second digit is the diameter series: 60 is the smallest standard section (310×51 mm, 55.0 mm radial section) at 200 mm bore — below 62/63/64 in load capacity, for light loads in compact spaces.
What is the NSK designation and catalogue data for 6040?
In the NSK Rolling Bearings catalogue (E1103 Part C) this size is listed as 6040 — the open (unsealed) execution, 200×310×51 mm per ISO 15. Quoted values: C 228 kN, C0 226 kN, mass 12000 g. The industry-neutral page spelling 6040 follows the seal-suffix convention used across this site, not NSK order-number spelling. Reference and limiting speeds are not tabulated in the E1103 dimension tables used here; consult NSK speed tables before high-speed service.
Reviewed & verified by the MPN Base engineering desk against source catalog NSK Rolling Bearings E1103 Part C on 2026-09-24. Read our editorial & correction policy.