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 |
|---|---|
| Brand | SKF |
| 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 |
|---|---|---|---|
| 6418-2RS | 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. |
| 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. |
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
6418 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the heavy 64xx section (diameter series 4 of ISO 15), multiplying bore code 18 by five gives the 90 mm bore; the 225 mm outside diameter and 54 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 90 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the SKF catalogue this open execution carries the bare designation; protected variants are ordered separately as -2Z and -2RSH.
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
- 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
- Large bores like the 90 mm of 6418 demand clean, burr-free seats; one raised burr under a ring this size cocks the bearing and concentrates load at the raceway edge, cutting life drastically.
- 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.
- Storage matters for open bearings: 6418 leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
- 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.
- Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 54 mm-wide ring of 6418 drags the lip and overheats it.
- The housing bore for the 225 mm OD should be round within IT7; an oval bore pinches the outer ring of 6418 and shows up later as two-point loaded raceway wear.
- 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.
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.
Are 6418 bearings from different brands interchangeable?
For boundary dimensions, yes: every brand's 6418 uses the same ISO 15 envelope (90×225×54 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting.
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.