K40X45X27 bearing: complete specifications & equivalents
The K40X45X27 is a DIN 5402 radial bearing sized 40 x 45 x 27 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 40 mm |
| Outer diameter D | 45 mm |
| Width B | 27 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 31.4 kN |
| Basic static load rating C0 | 73.5 kN |
| Fatigue load limit Pu | 9 kN |
| Reference speed (thermal) | 10000 rpm |
| Limiting speed (mechanical) | 12000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 46 g |
| Manufacturer designation | K 40x45x27 |
| Standard | DIN 5402 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.1 needle roller and cage assemblies |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.1 needle roller and cage assemblies) · extracted 2026-09-26
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.1 needle roller and cage assemblies); 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 & K-series range
| Bore d | 1.575 in |
|---|---|
| Outer diameter D | 1.772 in |
| Width B | 1.063 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 2.5 mm |
| Smallest bore in K-series | 3 mm |
| Largest outer diameter in K-series | 63 mm |
| Width range across K-series | 7–32 mm |
| Bore position in K-series (smallest first) | 16 of 22 |
| Bore above smallest K-series size | 37 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the K40X45X27 model number is decoded
For pivots and crank pins where every millimetre of radial height counts, SKF supplies K 40x45x27: needle rollers in a pressed cage (DIN 5402 boundary plan), dimensioned Fw 40 × E 45 × B 27 mm. In the K code K 40x45x27, Fw×E×B reads directly as journal 40 mm, complement diameter 45 mm and cage width 27 mm; the housing bore is ground to E with H6/H7 tolerance to complete the outer raceway. No suffix on the order number means the standard single-row assembly; the polymer TN cage version is the usual choice for grease-lubricated pivots where noise matters. For life calculation, the 31.4/73.5 kN ratings assume raceway geometry supplied by the shaft and housing in families without an inner ring — journal hardness, roundness and finish are part of the bearing, not of the application. The assembly is drawn on over a mounting sleeve that spreads the load around all rollers; never drive it home against the cage face, and retain it with a washer whose OD spans the cage, not the rollers.
Typical equipment & failure modes
Common applications
- hinge and pivot joints in printing and textile machinery
- universal joint crosses on commercial vehicles
- planetary gear pins in compact transmissions
- connecting rods of small compressors where radial height is critical
Known failure patterns
- raceway spalling once the catalogue L10 life is exceeded or after overload events
- polymer cage deformation when the local temperature exceeds the 120 °C sustained limit
- abrasive paste formation from dust ingressing past open ends without effective housing seals
- brinelling of raceways from impact or pressing force transmitted through the rolling elements
- rapid raceway scoring when the shaft journal hardness drops below 58 HRC or the ground finish wears away
Selection pitfalls — read before you substitute
- At 40 mm bore, verify shaft deflection against the needle length: these rollers tolerate little edge loading, and a simply supported span between 40 mm seats can bend past the compensation range long before the load rating is exhausted.
- Hardness is load capacity: in families without an inner ring the 40 mm journal must hold 58–64 HRC with a ground finish; a surface that looks fine but sits at 45 HRC will rib the raceway within weeks.
- The quoted 31.4/73.5 kN ratings are SKF catalogue values for this exact execution (K 40x45x27); ratings can be revised without the order number changing, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the drawing.
- The 31.4/73.5 kN ratings and 46 g mass are SKF catalogue values transcribed from ch. 7.1 of PUB BU/P1 17000 (PDF table page 618); combined-type axial ratings appear in the text above because the structured record carries radial values only.
Frequently asked questions
What limits the service life of a K 40x45x27?
Beyond the L10 rating, the practical limits are journal/raceway hardness for the 40 mm seat, lubricant condition at the roller ends, and contamination through open ends — the 2.5 mm radial section leaves no reserve once a raceway is dented or ribboned.
What are the dimensions and ratings of the K 40x45x27?
A K 40x45x27 measures 40 mm bore/Fw × 45 mm outside diameter × 27 mm width (1.575 × 1.772 × 1.063 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 31.4 kN, static C0 73.5 kN, fatigue limit Pu 9 kN, limiting speed 12,000 r/min, reference speed 10,000 r/min, mass about 46 g.
How is the K 40x45x27 designation read?
K = needle roller and cage assembly (DIN 5402); the three figures give Fw 40 mm (shaft journal), E 45 mm (complement outside diameter, matched by the housing bore) and B 27 mm width. TN marks the glass fibre reinforced PA66 cage.
Can the K 40x45x27 run on an unhardened shaft?
No. In this execution the 40 mm shaft journal is the inner raceway: it must be ground and hardened to 58–64 HRC (with matching housing bore quality on the outside). If the shaft cannot meet that, order the inner-ring sibling (NKI/NA execution) plus its ground inner ring instead.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.1 needle roller and cage assemblies on 2026-09-26. Read our editorial & correction policy.