3307-A-2Z bearing: complete specifications & equivalents

Specification table

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.

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 3307-A-2Z model number is decoded

3307 A-2Z is the capped double-row angular-contact ball bearing for a 35 mm shaft, 35×80×34.9 mm, greased and sealed (or shielded) for life at the SKF works. A on this double-row bearing means no filling slots, so both ball rows retain their full complement. -2Z marks a sheet-metal shield on each side: non-contacting, grease-retention and dust protection with negligible drag, the bearing remaining open-style relubricatable only through the shield clearance. Envelope 35×80×34.9 mm (1.378×3.15×1.374 in), 22.5 mm radial section height, C 52 kN, C0 35.5 kN, Pu 1.5 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 740 g. Sizing arithmetic on the 35 mm bore: 52 kN C divided by the 22.5 mm radial section height gives 2.3 kN per section millimetre; the 740 g mass and 3 % Pu/C share frame the light-load floor for the adjusted-life check. Load balance: C0 35.5 kN against C 52 kN gives a 0.68 ratio, typical of a steep-angle axial-oriented design; Pu 1.5 kN enters the SKF adjusted-life equation rather than the basic rating life. Bore-to-OD planning: OD 80 over bore 35 is a 2.29× step for this size, and the 34.9 mm width gives a bore/width ratio of 1.00; use these ratios when housing space around the 35 mm shaft is the first constraint. Shielded execution note: the two sheet-metal -2Z covers clip into the outer ring without contacting the inner ring, giving grease retention and coarse-dust protection at virtually no friction; the cavity is factory-greased and the shield arrangement suits dry, moderately dusty positions rather than wash-down duty, where the A-2RS1 contact-seal order number is the alternative.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• The shields/seals do not make the bearing waterproof under immersion or pressure washing; select external sealing for wet or wash-down duty.
• Fit and fillet rules are unchanged from the open double-row 3307: k5 on a 35 mm rotating shaft, radii clearing the chamfer.
• Fit and fillet rules are unchanged from the open double-row 3307: k5 on a 35 mm rotating shaft, radii clearing the chamfer.
• The non-contact shields cap the speed with negligible drag: no relubrication is provided for, so mounting cleanliness decides much of the real grease life.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 3307 A-2Z as the double shielded execution; the other order numbers of the 3307 size are different products and may carry different ratings — always quote the full designation when purchasing.