21316-EK bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.2 adapter-sleeve executions) · extracted 2026-09-26

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.2 adapter-sleeve executions); 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 21316-EK model number is decoded

For sleeve mounting on a 80 mm shaft, SKF order number SKF 21316 EK is the 1:12 tapered-bore spherical roller bearing in the 21300-series family (dimension series 13 (heavy OD, normal width)); the cylindrical-bore equivalent is a separate order number, 21316. Reading the designation: the leading 2 marks a spherical roller bearing, the 13 is the ISO 15 dimension series (dimension series 13 (heavy OD, normal width)), and the last two digits encode the 80 mm bore; the 170 mm OD and 39 mm width follow the ISO 15 general plan. Note that K means 1:12 taper; the rarer K30 suffix means 1:30. Adapter sleeves (H) and withdrawal sleeves (AH) are ordered separately by shaft diameter, and the KM locknut plus MB lock washer used for drive-up are also separate components. Catalogue mass 5300 g for the 80×170×39 mm open execution covers the two pressed-steel cages with a floating guide ring; tapered-bore and sealed variants differ in mass and carry their own order numbers. Because driving up the 1:12 taper consumes radial clearance, K executions are commonly ordered with C3 initial clearance so the residual running clearance after mounting matches the cylindrical-bore 21316 on an interference seat.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Mount the 80 mm bore 21316-ek by induction heating (max 120 °C) or oil injection — driving a bearing of this section home through the rollers brinells both raceways, and the damage only speaks up as vibration hours later.
• The 21300-series series at 80 mm bore (170×39 mm) pairs a heavy OD with a narrow section — a compact way to add capacity, but the shoulder and abutment diameters differ from the 222 series; it is not a drop-in swap.
• The adapter sleeve is selected by actual shaft diameter, not by the 80 mm nominal bearing bore: H-sleeve part numbers span a small diameter range, so two different shaft diameters can use the same 21316-ek with different sleeves.
• A loose sleeve after the first weeks of service usually means inadequate initial drive-up; re-checking clearance without dismounting is possible through the 39 mm-wide roller rows with feeler gauges — do not simply tighten the KM nut until vibration stops.
• The self-aligning feature is not a license to ignore alignment: beyond ≈ 0.5–2.5° (series-dependent) the edge loading eats the fatigue margin, and seal drag grows as the rings tilt.
• The 331/375 kN ratings are SKF catalogue values for this tapered-bore execution (SKF 21316 EK); sleeve, KM nut and MB washer are separate order numbers, and the catalogue version (SKF catalogue PUB BU/P1 17000) should travel with the mounting specification.