NUKR40 bearing: complete specifications & equivalents

Specification table

Source: catalog reference (HR1 2026-09-25) · extracted 2026-09-30

Parameters extracted from the official FAG Rolling Bearings catalogue (HR1 2026-09-25); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.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 NUKR40 model number is decoded

envelope 18×40×58 mm: the 40 mm outside diameter is the track-running surface — a thick-walled outer ring over a 18 mm stud — and the 58 mm overall stud-and-roller length sets the required bracket clearance the catalogue lists C 18.8 kN and C0 25.5 kN for the NUKR double-row full-complement stud-type track roller; the C/C0 ratio of 0.74 reflects a rolling-element pack sized for heavy static track loading, and the 11.0 mm radial section gives the outer ring its bending stiffness fatigue load limit Cur is 3.25 kN at 18 mm stud, equivalent to 1.04 kN of dynamic rating per millimetre — the limiting speed is 5,500 r/min and, as for HR1 track rollers, no thermal reference speed is published the 18 mm threaded stud clamps directly into the machine bracket; over the roller running width the dynamic rating works out to 0.32 kN per millimetre of rolling-element complement within the 58 mm overall stud length mass is 242 g, or 0.10 g per mm² of the 40×58 mm track envelope — inertia that the drive must accelerate on every index of the cam with a 18 mm stud shank the 58 mm width and 18.8 kN C rating suit high-cycle industrial machinery rather than instrument duty The 18 mm stud clamps into the machine frame with its nut and washer while the 40 mm thick-walled, crowned-profile outer ring runs on the cam; overall length is 58 mm Reading the designation: no eccentric collar is fitted — the roller centre is fixed by the stud axis, with labyrinth-style protection at the faces Typical applications include packaging machine timing mechanisms, woodworking machine feed tracks and agricultural and textile cam followers, where the 40 mm track diameter and 18.8 kN dynamic rating match the duty. In packaging machine timing mechanisms the threaded stud bolts directly to the frame, and in woodworking machine feed tracks the 242 g mass keeps follower kinetics light. Designers also specify it for agricultural and textile cam followers, relying on the 58 mm stud length and the published 25.5 kN static rating. Never hammer the stud or use the hex socket as a press point during mounting; thread or socket damage renders the 58 mm stud unusable. Use a washer under the nut and a flat square bracket face; the stud head alone cannot spread the clamp load of the heavy double-row executions.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Never hammer the stud or use the hex socket as a press point during mounting; thread or socket damage renders the 58 mm stud unusable.
• Use a washer under the nut and a flat square bracket face; the stud head alone cannot spread the clamp load of the heavy double-row executions.
• The eccentric collar throw is small (typically around 1 mm); it removes clearance, it cannot repair a grossly misplaced bracket.