32938 bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB) · extracted 2026-09-28

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB); 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 32938 model number is decoded

The SKF 32938 is a 190×260×45 mm single-row tapered roller bearing — the very-light thin section entry in the 32900 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 29 is the ISO 355 diameter/width series (very-light thin section), and the last two digits encode the 190 mm bore; the 260 mm OD and 45 mm width follow the ISO 355 general plan. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 4DC); it is the dimensional series, not a separate part number. Catalogue mass 7000 g for the 190×260×45 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Because the contact line is tapered, one 32938 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 190 mm shaft typically takes a m6 seat with an H7 housing bore. Operating context for the 190 mm bore: a shaft of this diameter in the xl-bore band typically runs between 152000 and 228000 r/min in real machinery, and the 260 mm outside diameter places the housing shoulder at 268 mm outer abutment; the 45 mm width and 7000 g mass together set the shaft critical speed and the housing resonance check for this 32900-series envelope.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 190 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.
• The 329 series at 190 mm bore (260×45 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30238 of the same bore — confirm the L10 life and minimum axial load before choosing it.
• When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32938 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.
• At the 443 kN rating of 32938, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,200 r/min speed end and heavier preload only where moment stiffness dominates.
• Shaft and housing fillets must clear the bearing chamfer so the 45 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.
• The 443/765 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.
• SKF lists several executions of 32938 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32938 designation when purchasing and match the execution to the mounting arrangement.