KR-52-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-52-PPA model number is decoded

the 52 mm outside diameter runs on the track while the 20 mm stud shank takes the pin or shaft; the 66 mm overall width spreads the Hertzian contact over the outer ring published ratings C 15.7 kN and C0 27 kN already include the bending-stress correction for the unsupported outer ring — the C/C0 ratio of 0.58 is typical for cam follower with needle roller and cage executions fatigue load limit Pu 3.2 kN at 20 mm stud gives a specific load of 0.78 kN per mm; the limiting speed is 3,000 r/min the 66 mm width carries the load at 0.24 kN per mm of roller complement; section height 16.0 mm between stud and track surface determines the outer-ring bending stiffness mass 450 g over a 52x66 mm envelope works out to 0.131 g per mm² of projected area — a useful figure when sizing the drive inertia for medium-speed cam duty the 20 mm stud diameter falls in the small-size band, the most common choice for general-purpose cam followers and light conveyor transfer rollers KR is the fundamental stud-type track roller: a single-row needle roller and cage unit pressed onto a threaded stud, offering the highest limiting speed of the cam follower range PPA changes the outer-ring profile from cylindrical to crowned; the barrel shape lowers edge stress when the cam track is not perfectly parallel to the roller axis typical applications include food processing line track rollers, printing press roller followers and automotive welding jig positioners this size is commonly specified for food processing line track rollers and printing press roller followers, where the 52 mm track diameter and 20 mm stud fit standard cam and rail geometries in automotive welding jig positioners the 52 mm outer ring provides the rolling contact while the threaded stud simplifies mounting; the 450 g mass is low enough for rapid indexing cycles the stud shank must be fully supported by the bracket; a cantilevered stud bends under load and misaligns the roller the cage-guided needle rollers are not suited to heavy shock — impact loads can crack the cage and release rollers

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• the single-row needle complement is the lightest cam follower option; do not overload it beyond the printed C rating
• the stud shank must be fully supported by the bracket; a cantilevered stud bends under load and misaligns the roller
• the stud head is relatively small; use a washer under the nut to spread the clamping load and prevent bracket surface damage