52408 bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-28

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.

Cross references & equivalents

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 52408 model number is decoded

Listed in SKF 17000 chapter 5, 52408 is an ISO 104 double-direction thrust ball bearing, 30 mm bore and 90 mm OD on a flat housing seat, standing 65 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52408 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 30×90×65 mm (1.181×3.543×2.559 in), 30.0 mm radial section, C 95.6 kN, C0 183 kN, Pu 6.8 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2050 g. Pitch-diameter arithmetic: dm = (30+90)/2 = 60.0 mm; at the 2,400 r/min limiting speed that corresponds to roughly 144k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Track-circle loading: per millimetre of mean track circumference the 95.6 kN dynamic rating corresponds to roughly 0.51 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Rating split for documentation: dynamic 95.6 kN (L10 life), static 183 kN (safety factor s0), fatigue limit 6.8 kN (adjusted life) — three different uses of three different numbers for 52408, none interchangeable with another. Sizing arithmetic on the 30 mm bore: 95.6 kN C over the 30.0 mm radial section gives 3.2 kN per section millimetre, and the 65 mm stack height is 2.17× that section — proportions typical of a 52400 thrust section. Static-first selection data: 183 kN C0 spread across the 65 mm stack gives 2.8 kN of static rating per height millimetre, and the 2050 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52408 is done separately per direction: if duty applies 95.6 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.
• Do not replace a 52408 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×90 mm bore and OD.
• The double-direction 52408 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 30 mm shaft axially in both directions instead of a mirrored pair.
• Each direction independently needs the minimum axial load (factor A 0.26): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.
• The 95.6/183 kN figures belong to 52408 specifically (the double flat pressed steel execution of 52408); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record.