KR40 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 KR40 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 10.9 kN and C0 16 kN for the KR stud-type cam follower with needle roller and cage assembly; the C/C0 ratio of 0.68 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 2.13 kN at 18 mm stud, equivalent to 0.61 kN of dynamic rating per millimetre — the limiting speed is 2,900 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 0.19 kN per millimetre of rolling-element complement within the 58 mm overall stud length mass is 247 g, or 0.11 g per mm² of the 40×58 mm track envelope — inertia that the drive must accelerate on every index of the cam the 18 mm stud shank falls in the small band, the workhorse size for gearbox planetary positions, hydraulic pumps and general cam and linkage duty The caged pack keeps friction and inertia low — at 247 g this is the follower for fast indexing drives and high-cycle linkages Reading KR/KRV/KRE: stud-type needle cam followers in the open execution and a 58 mm overall stud length Typical applications include agricultural and textile cam followers, packaging machine timing mechanisms and robotic arm linear axes, where the 40 mm track diameter and 10.9 kN dynamic rating match the duty. In agricultural and textile cam followers the threaded stud bolts directly to the frame, and in packaging machine timing mechanisms the 247 g mass keeps follower kinetics light. Designers also specify it for robotic arm linear axes, relying on the 58 mm stud length and the published 16 kN static rating. On eccentric KRE/NUKRE/PWKRE units, re-torque after setting the collar — the adjustment changes the effective stud engagement. Sealed PP/2RS followers are life-lubricated; open KR/NUKR executions need the stud greaseway serviced on a fixed interval.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• On eccentric KRE/NUKRE/PWKRE units, re-torque after setting the collar — the adjustment changes the effective stud engagement.
• Sealed PP/2RS followers are life-lubricated; open KR/NUKR executions need the stud greaseway serviced on a fixed interval.
• The eccentric collar throw is small (typically around 1 mm); it removes clearance, it cannot repair a grossly misplaced bracket.