305706-C-2Z bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 14 cam rollers) · extracted 2026-10-14

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 14 cam rollers); 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

No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.

How the 305706-C-2Z model number is decoded

the 72 mm outside diameter is the crowned track contact surface, the 30 mm bore takes the pin and the 23.8 mm overall width spreads the Hertzian contact across the thick-walled outer ring published ratings C 25.1 kN and C0 16.3 kN already include the outer-ring bending correction that track rollers require; the C/C0 ratio of 1.54 reflects two ball sets at a 30 deg contact angle fatigue load limit Pu 0.695 kN against a 30 mm bore gives 0.84 kN per mm of bore, and the 5,000 r/min figure is a mechanical limit rather than a thermal one the maximum permissible radial loads are Fr 17 kN dynamically and F0r 24 kN statically; because the permissible static load is the lower of F0r and C0, the 16.3 kN figure governs static selection here the 23.8 mm width carries 1.05 kN per mm, the ring section measures 21.0 mm between bore and track surface, and 490 g over a 72x23.8 mm envelope is 0.286 g per mm2 of projected area for medium-speed cam duty the 30 mm bore and 23.8 mm width are those of the 32 series ball bearing at the same size code, while the 72 mm outside diameter is 10 mm larger than that bearing's 62 mm OD — this follows the SKF rule that cam rollers keep the ISO 15 dimension series except for the outside diameter the 30 mm bore puts this at the top of the cam roller range, where the 72 mm ring and 490 g mass make it a drive-design factor rather than a minor component 3057 is the flat-running-surface double row cam roller: the same 30 deg double row angular contact basis as 3058, but with a cylindrical (flat) outer ring instead of a crowned one the 30 deg contact angle of the two ball sets is what gives the double row roller its tilting stiffness — under a moment load the rows react in opposite directions instead of unloading one edge of the ring the 2Z suffix means sheet steel shields on both sides rather than elastomeric seals: they keep coarse debris out but will not retain a grease fill as tightly as the NBR contact seals of the single row roller typical duties are sheet metal forming press feeds, tube and wire drawing guides and material handling lift tracks this size is regularly specified for sheet metal forming press feeds and tube and wire drawing guides, where the 72 mm ring rides the cam profile and the 30 mm bore takes a g6 pin the two ball rows and the 23.8 mm wide ring make material handling lift tracks a natural fit; the 490 g mass keeps the follower inertia low enough for rapid oscillating cam motion relubrication depends on the inner-ring lubrication hole and a drilled pin; if neither is provided, grease replacement needs the roller dismantled from the yoke the flat running surface assumes an accurately aligned track; angular misalignment between the roller axis and the guide surface puts the whole load onto the ring edges

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• the flat running surface assumes an accurately aligned track; angular misalignment between the roller axis and the guide surface puts the whole load onto the ring edges
• relubrication depends on the inner-ring lubrication hole and a drilled pin; if neither is provided, grease replacement needs the roller dismantled from the yoke
• the cylindrical ring offers no crown relief, so any track crown, deflection or parallelism error shows up directly as edge stress and shortened ring life