NATR-20 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 NATR-20 model number is decoded

the 47 mm outside diameter runs on the track while the 20 mm bore takes the pin or shaft; the 25 mm overall width spreads the Hertzian contact over the outer ring published ratings C 14.7 kN and C0 24.5 kN already include the bending-stress correction for the unsupported outer ring — the C/C0 ratio of 0.60 is typical for support roller with flange rings, with inner ring executions fatigue load limit Pu 2.9 kN at 20 mm bore gives a specific load of 0.73 kN per mm; the limiting speed is 3,000 r/min the 25 mm width carries the load at 0.59 kN per mm of roller complement; section height 13.5 mm between bore and track surface determines the outer-ring bending stiffness mass 250 g over a 47x25 mm envelope works out to 0.213 g per mm² of projected area — a useful figure when sizing the drive inertia for medium-speed cam duty the 20 mm bore 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 NATR execution is the caged, flanged variant — cage guidance gives a higher limiting speed than the full-complement NATV, while the flanges simplify housing design by eliminating separate thrust faces typical applications include cam mechanisms and indexing drives, material handling lift and lower tracks and sheet-metal forming press feeds this size is commonly specified for cam mechanisms and indexing drives and material handling lift and lower tracks, where the 47 mm track diameter and 20 mm bore fit standard cam and rail geometries in sheet-metal forming press feeds the 47 mm outer ring provides the rolling contact while the inner ring bore simplifies mounting; the 250 g mass is low enough for rapid indexing cycles the cage material is typically polyamide or steel; at temperatures above 100 degC polyamide cages soften and lose guidance function the pressed-on flange rings are not designed for continuous axial load — side thrust from a skewed track will eventually dislodge them

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• cage guidance (NATR) is less tolerant of shock than full complement (NATV); heavy impact can crack the cage and release rollers into the mechanism
• the cage material is typically polyamide or steel; at temperatures above 100 degC polyamide cages soften and lose guidance function
• the flange rings are a press fit on the inner ring; excessive axial preload during mounting can shift them and alter the internal clearance