7309-BEGAPH 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 7309-BEGAPH model number is decoded

7309 BEGAPH is SKF's 45 mm-bore single-row angular-contact ball bearing in the 7300 series, nominal 40° (B) contact angle, 45×100×25 mm to the ISO dimension plan. 40° contact angle (suffix B): the steep standard single-row angle, giving the highest axial capacity at the cost of speed, with a recommended load ratio Fa/Fr ≥ 1. E marks the optimized internal design with an enhanced ball complement and race geometry. glass-fibre reinforced PEEK cage, ball-centred (suffix PH), keeping the polymer-cage speed advantage well above the PA66 temperature range. GA marks universal matching with light factory preload for back-to-back or face-to-face sets — stiffer than CB clearance while generating less heat than GB/GC. BEGAPH combines light-preload (GA) universal matching with a PEEK ball-centred cage. Envelope 45×100×25 mm (1.772×3.937×0.984 in), 27.5 mm radial section height, C 61 kN, C0 40.5 kN, Pu 1.73 kN.reference speed 8,500 r/min (thermal) and limiting speed 9,000 r/min (mechanical), catalogue mass 820 g. Sizing arithmetic on the 45 mm bore: 61 kN C divided by the 27.5 mm radial section height gives 2.2 kN per section millimetre; the 820 g mass and 3 % Pu/C share frame the light-load floor for the adjusted-life check. Envelope economics: the 25 mm width over a 27.5 mm section yields 0.91 mm of ring width per section millimetre, and the bearing weighs 820 g for 61 kN of dynamic capacity — about 13 g per rated kN. Bore-to-OD planning: OD 100 over bore 45 is a 2.22× step for this size, and the 25 mm width gives a bore/width ratio of 1.80; use these ratios when housing space around the 45 mm shaft is the first constraint. Preload and cage note: BEGAPH arrives as a universally matchable unit with GA light preload already defined for back-to-back or face-to-face sets, combined with the glass-fibre PEEK ball-centred cage for high-speed duty; it replaces field preload adjustment, not the need for correct stand-off geometry.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 45 mm bore the k5 seat assumes a steel shaft and housing; aluminium housings grow faster with temperature, so re-check the outer-ring setting when the case is non-ferrous.
• Greased positions should fill roughly 25–35 % of the free volume on a 7309-BEGAPH of this section and route the surplus past the outer ring; overpacking churns the grease and reproduces the thermal preload problem mechanically.
• Reference and limiting speeds are different ceilings: design to both, and remember preload and oil/air cooling move the real thermal limit far from the catalogue reference value.
• Fillet radii must clear the chamfer so the 25 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
• The steep 40° angle of 7309-BEGAPH favours thrust-heavy combined loads; for a predominantly radial high-speed position the 25° ACCBM execution of the same size is the alternative order number.
• Universally matchable BEGAPH bearings arrive ready for set mounting, not preloaded sets: preload results from how the set is clamped, so follow the SKF stand-off-ring and nut-torque procedure.