1318-K bearing: complete specifications & equivalents
The 1318-K is a ISO 15 radial bearing sized 90 x 190 x 43 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 | 190 mm |
| Width B | 43 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 117 kN |
| Basic static load rating C0 | 44 kN |
| Fatigue load limit Pu | 1.93 kN |
| Reference speed (thermal) | 6700 rpm |
| Limiting speed (mechanical) | 4500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5800 g |
| Manufacturer designation | 1318 K |
| 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 & 1300-series range
| Bore d | 3.543 in |
|---|---|
| Outer diameter D | 7.48 in |
| Width B | 1.693 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 50 mm |
| Smallest bore in 1300-series | 5 mm |
| Largest outer diameter in 1300-series | 320 mm |
| Width range across 1300-series | 6–74 mm |
| Bore position in 1300-series (smallest first) | 20 of 29 |
| Bore above smallest 1300-series size | 85 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 1318 | NTN | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance 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 1318-K model number is decoded
The 13xx series is the medium/normal-section self-aligning ball bearing (ISO dimension series 03). the last two digits encode the bore: 1318 carries code 18 = 90 mm (code × 5). Envelope 90×190×43 mm (3.543×7.48×1.693 in) with a 50.0 mm radial section height, C 117 kN, C0 44 kN and Pu 1.93 kN. The open 1318 K carries no shields or seals and relies on application lubrication and external sealing. The suffix identifies the glass-fibre-reinforced polyamide 66 cage execution. The K suffix marks a 1:12 tapered bore for direct mounting on a tapered shaft or with an adapter sleeve. Reference (thermal) speed 6700 r/min, limiting speed 4500 r/min, catalogue mass 5800 g.
Typical equipment & failure modes
Common applications
- textile machinery drives
- industrial fans and blowers
- woodworking machinery
- pump shafts with mild misalignment
Known failure patterns
- contamination wear when the open arrangement is used without adequate external sealing
- lubricant starvation where no regreasing interval is maintained
- adapter-sleeve fretting when the sleeve is not locked against the shaft shoulder
- incorrect sleeve tightening that leaves the tapered bore loose or over-expanded, changing internal clearance
- raceway smearing under marginal lubrication at start-up
- electrical pitting in VFD-driven motors without shaft grounding
Selection pitfalls — read before you substitute
- Catalogue ratings for 1318-K (C 117 kN, C0 44 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 spherical outer raceway lets 1318-K tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
- The K suffix means a 1:12 tapered bore: 1318-K is not a drop-in for the straight-bore version — it needs a tapered shaft or an H-series adapter sleeve.
- The suffix on 1318-K denotes a glass-fibre-reinforced polyamide 66 cage: quiet and light at the 4500 r/min limiting speed, but it softens above roughly 120 °C — check the oil temperature in hot drives.
- The spherical outer raceway lets 1318-K tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
- Fillet radii must clear the 1318-K chamfer so the 43 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
Frequently asked questions
What are the dimensions of 1318-K?
SKF 1318 K measures 90 mm bore × 190 mm OD × 43 mm width (3.543 × 7.48 × 1.693 in), mass about 5800 g. It is open, with no shields or seals.
How does the bore code in 1318 work?
The final two digits of 1318 are bore code 18, multiplied by 5 to give 90 mm.
How heavy is 1318-K?
Catalogue mass is 5800 g for 1318 K; seal and cage executions of the same envelope differ by a few grams.
What load can 1318-K take?
Catalogue values for 1318 K: dynamic C 117 kN, static C0 44 kN, fatigue limit Pu 1.93 kN. Use C in life calculation and C0 for static checks at 90 mm bore.
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.