6418 bearing: complete specifications & equivalents
The 6418 is a ISO 15 radial bearing sized 90 x 225 x 54 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 90 mm |
| Outer diameter D | 225 mm |
| Width B | 54 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 186 kN |
| Basic static load rating C0 | 150 kN |
| Fatigue load limit Pu | 5 kN |
| Reference speed (thermal) | 6700 rpm |
| Limiting speed (mechanical) | 4300 rpm |
| Operating temperature | -40 to +150 °C |
| Mass | 9800 g |
| Manufacturer designation | SKF 6418 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-24 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
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 & 6400-series range
| Bore d | 3.543 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 2.126 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 67.5 mm |
| Smallest bore in 6400-series | 10 mm |
| Largest outer diameter in 6400-series | 250 mm |
| Width range across 6400-series | 12–58 mm |
| Bore position in 6400-series (smallest first) | 19 of 21 |
| Bore above smallest 6400-series size | 80 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6418-ZZ | GENERIC-ISO | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×225×54 mm envelope per ISO 15; seal variant differs (OPEN vs ZZ) — confirm sealing suits the duty. |
| 6418-2RS | GENERIC-ISO | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×225×54 mm envelope per ISO 15; seal variant differs (OPEN vs 2RS) — confirm sealing suits the duty. |
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 6418 model number is decoded
In the 6400-series (ISO 15 diameter series 4) the last two digits encode the bore: 6418 carries bore code 18 = 90 mm. Outside diameter 225 mm and width 54 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 90 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- medium and heavy industrial drives
- large gearboxes
- industrial fans and blowers
- hoists and winches
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- electrical pitting in VFD-driven motors without grounding protection
- raceway smearing under marginal lubrication at start-up
Selection pitfalls — read before you substitute
- Mount this 90 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 64xx heavy section at 90 mm bore (225 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm motor gives excess heat and short grease life — use 62/63 there.
- The open 6418 has no lubricant retention: grease escapes and contaminants migrate straight into the 90×225×54 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 6400-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6418 units.
- Do not quieten a noisy bearing by preloading it: the 6400-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
- The open 6418 needs external sealing and application-supplied lubrication; in the SKF catalogue the protected variants are separate order numbers 6418-2Z (shields) and 6418-2RSH (contact seals), not suffix-free 6418.
- The 186/150 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 6418 bearing?
A 6418 deep-groove ball bearing has a 90 mm bore, 225 mm outer diameter and 54 mm width (3.543 × 8.858 × 2.126 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How does the 6418 bore code work?
The last two digits of 6418 are bore code 18, giving 18 × 5 = 90 mm bore. The 225 mm outside diameter and 54 mm width follow the ISO 15 diameter series, not the bore code alone.
What does no suffix on 6418 mean?
A bare 6418 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 6400 compare with other series at the same 90 mm bore?
The '4' is the heavy diameter series: 225×54 mm, 67.5 mm radial section at 90 mm bore — the highest-capacity single-row 6xx option here, aimed at lower-speed, high-load shafts.
What is the SKF designation and catalogue data for 6418?
In the SKF Rolling Bearings catalogue this size is listed as 6418 — the open (unsealed) execution, 90×225×54 mm per ISO 15. Quoted values: C 186 kN, C0 150 kN, Pu 5 kN, limiting speed 4300 r/min, mass 9800 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 6418.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.