KR-40-PPA bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 15 support rollers / ch. 16 cam followers) · extracted 2026-09-30

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 15 support rollers / ch. 16 cam followers); 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 KR-40-PPA model number is decoded

the 40 mm outside diameter runs on the track while the 18 mm stud shank takes the pin or shaft; the 58 mm overall width spreads the Hertzian contact over the outer ring published ratings C 10.5 kN and C0 14.6 kN already include the bending-stress correction for the unsupported outer ring — the C/C0 ratio of 0.72 is typical for cam follower with needle roller and cage executions fatigue load limit Pu 1.73 kN at 18 mm stud gives a specific load of 0.58 kN per mm; the limiting speed is 3,400 r/min the 58 mm width carries the load at 0.18 kN per mm of roller complement; section height 11.0 mm between stud and track surface determines the outer-ring bending stiffness mass 240 g over a 40x58 mm envelope works out to 0.103 g per mm² of projected area — a useful figure when sizing the drive inertia for medium-speed cam duty the 18 mm stud shank puts this in the small-to-medium transition where the roller complement is still needle-type but the outer ring is thick enough for moderate shock loads the KR prefix identifies the standard stud-type cam follower — needle rollers with cage guidance between the 18 mm stud and the 40 mm thick-walled outer ring PPA denotes the crowned running surface: the 40 mm OD is ground to a large radius rather than straight, reducing edge loading on misaligned cam tracks typical applications include automatic assembly machine linkages, food processing line track rollers and printing press roller followers this size is commonly specified for automatic assembly machine linkages and food processing line track rollers, where the 40 mm track diameter and 18 mm stud fit standard cam and rail geometries in printing press roller followers the 40 mm outer ring provides the rolling contact while the threaded stud simplifies mounting; the 240 g mass is low enough for rapid indexing cycles the single-row needle complement is the lightest cam follower option; do not overload it beyond the printed C rating the stud head is relatively small; use a washer under the nut to spread the clamping load and prevent bracket surface damage

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• the stud thread must be torqued to the catalogue value; under-torque lets the follower rotate and wear the bracket hole
• the single-row needle complement is the lightest cam follower option; do not overload it beyond the printed C rating
• the stud head is relatively small; use a washer under the nut to spread the clamping load and prevent bracket surface damage