The dynamic load rating of 42.3 kN characterises this bearing. The static load rating is 24 kN. The limiting speed is 11000 rpm. This variant features greatly increased radial clearance (C4). Point contact between ball and raceway keeps frictional torque low, which is why this type runs faster and cooler than any other rolling bearing. The deep, closely conforming raceway grooves in the inner and outer ring capture the balls positively, so the bearing takes radial load and moderate axial load in both directions without a second bearing position to oppose it.
Because the ball touches the raceway at a point, friction and heat stay low — the precondition for high speeds and for grease-for-life designs. The limits follow from that same geometry: the small contact area caps load capacity against a roller bearing of equal size, and the bearing tolerates misalignment within narrow limits only, since angular error transfers straight into the raceway grooves.
Seats in shaft and housing must therefore be aligned and geometrically accurate; where shaft deflection is expected, a self-aligning type belongs in that position. The single shield runs without contact and holds back coarse contamination on its side; the open opposite side is left to the surrounding design, which seals it there or supplies the lubricant.
Rings and rolling elements are made of through-hardened standard bearing steel. The strongly increased radial clearance is intended for pronounced temperature differences between the rings or for very tight fits; without those conditions the bearing runs with unnecessary play. Heavily increased radial clearance C4 — Dimensional/form-fit equivalent — verify suffix-level details for critical applications. Matching suffixes are also listed by FAG (C4), NSK (C4), NTN (C4), NACHI (C4) and Timken (C4).
ManufacturerSKF
Bearing typeDeep-groove ball bearings
Bore d40 mm
Outer Ø D90 mm
Width B23 mm
Dyn. load C42.3 kN
Stat. load C₀24 kN
Fatigue limit Pu1.02 kN
Limiting speed11,000 min⁻¹
Reference speed17,000 min⁻¹
Weight0.618 kg
Sealsshield on one side
Clearanceradial internal clearance much greater than normal
Cagepressed steel cage
Materialstandard bearing steel
Tolerancetolerance class P0/PN (ABEC 1)
Shaft shoulder dₐ49–56.1 mm
Housing shoulder Dₐ73.8–81 mm
Bore typecylindrical bore
€22.79/ pc€35.16−35 %
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Lowest price in the 30 days before the reduction: €35.16
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QtyUnit priceDisc.
1 – 4€22.79—
5 – 9€22.11−3 %
10 – 24€21.65−5 %
25 – 49€20.97−8 %
50 – 99€20.51−10 %
4 more for −3% volume discount
From 100 pcs: price and lead time on request – subject to review.
Total (1 pc)€22.79
SKF 6308-Z/C4 Kugellager (40x90x23)
— 40 x 90 x 23 mm
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Same dimensions means the same bearing type and matching main dimensions (d × D × B). Sealing, cage, internal clearance and execution (e.g. material, precision, grease fill) are encoded in the suffix and may differ — please check before ordering. Equivalent additionally means the same sealing, internal clearance and tolerance class; the cage and other suffix features (e.g. lubrication groove) may differ.
