52406 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 52406 model number is decoded

52406 is SKF's 20 mm-bore double-direction thrust ball bearing in the 52400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 20×70×52 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 20 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 20×70×52 mm (0.787×2.756×2.047 in), 25.0 mm radial section, C 70.2 kN, C0 122 kN, Pu 4.5 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1000 g. Envelope economics: the 52 mm axial height over a 25.0 mm radial section yields 1.4 kN of dynamic capacity per height millimetre, and the bearing weighs 1000 g for 70.2 kN C — about 14 g per rated kN. At the printed limiting speed of 3,200 r/min the mean pitch diameter dm ≈ 45.0 mm implies a dn value around 144k mm·r/min; the 2,200 r/min reference speed is the thermal-planning value under catalogue load. Speed band width for this size is 1,000 r/min between reference and limiting (1.45× ratio); lubrication, preload and heat removal decide where inside that band 52406 can actually run. Section proportions: the 25.0 mm radial section compares with 20 mm of bore (section/bore ≈ 1.25) and the 52 mm height is 2.08× that section — the proportions that identify the 52400 envelope at a glance. Light-load floor: Pu = 4.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52406; the number is 6 % of the 70.2 kN dynamic rating. 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. At 20 mm bore and 52 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 70 mm housing washers must remain free to slide during thermal movement.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Service both cage sets together: replacing only the noisy side while leaving the worn 122 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.
• Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 52 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.
• Each direction independently needs the minimum axial load (factor A 0.097): 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.
• 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.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 52406 as the double flat pressed steel execution; other order numbers of the 52406 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing.