61938-FAG bearing: complete specifications & equivalents

Specification table

Source: catalog reference (HR 1 Rolling Bearings (Jan 2020)) · extracted 2026-09-25

Parameters extracted from the official FAG Rolling Bearings catalogue (HR 1 Rolling Bearings (Jan 2020)); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.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 61938-FAG model number is decoded

61938 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the thin 619xx section (diameter series 9 of ISO 15), multiplying bore code 38 by five gives the 190 mm bore; the 260 mm outside diameter and 33 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 190 mm shaft under normal load, catalogue practice seats it on a m6 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the Schaeffler HR 1 catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes 2Z (steel shields), 2RZ (non-contact rubber seals) and 2RSR (lip-contact rubber seals).

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Mount this 190 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
• The 619xx thin section (35.0 mm section height at 190 mm bore) trades load capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
• The open 61938-FAG has no lubricant retention: grease escapes and contaminants migrate straight into the 190×260×33 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Open bearings tolerate the highest speeds in the 61900-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 61938 units.
• Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 61900-series position can soften the mixture and leak — clean out the old fill before switching grease types.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 33 mm-wide ring of 61938-FAG drags the lip and overheats it.
• The open 61938 has no integral sealing; in the Schaeffler HR 1 catalogue the protected variants carry suffixes 2Z (two steel shields), 2RZ (two non-contact rubber seals) and 2RSR (two lip-contact rubber seals). Do not confuse FAG's 2RZ with a contact seal — the RZ lip does not touch the inner ring, which is why its speed capability stays close to the open bearing.
• FAG lists the mechanical limiting speed at 3350 r/min for 61938 (thermal reference speed 3000 r/min); the thermal reference speed is the binding figure for continuous duty — size the lubrication interval off the reference speed, not the mechanical limit.
• The 190 mm bore places 61938 in Schaeffler's large-size range; at these diameters the pressed steel cage is speed-limited and FAG commonly offers a machined brass cage (suffix M) as an option. Verify cage material and relubrication provision with the distributor, and do not extrapolate small-bore speed ratings to this size.
• FAG rates 61938 at 140 kN dynamic (C) and 146 kN static (C0); this is an extreme-load rating at the top of the HR 1 single-row deep-groove range, where mounting, shaft stiffness and housing alignment dominate achievable life — request a Schaeffler application review rather than relying on catalogue L10 alone.
• At 4320 g (4.3 kg), 61938 needs mechanical handling for mounting; Schaeffler recommends induction heating the inner ring (max 120 °C) rather than pressing cold, and a lifting provision if the housing is pre-assembled.
• The 190×260×33 mm envelope of 61938 gives a D/d ratio of 1.37 and only 35.0 mm radial section height — an ultra-thin section in the HR 1 range where shaft deflection and housing ovality load the ball-raceway contact directly; verify shaft stiffness (target deflection under 0.05 mm) before choosing it over a 62-series.
• The 140/146 kN load ratings, mass 4320 g here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 61938-FAG on the 190×260×33 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61938 in a rated drive. Where FAG has since released an X-life version of this size, its expanded C/C0 ratings supersede the HR 1 print values quoted here.
• Schaeffler has moved many HR 1 sizes to the X-life generation with higher C/C0 ratings; the designation is unchanged, so a current eKatalog listing for 61938 may quote higher values than the HR 1 print figures on this page — the envelope is identical either way.
• Schaeffler's medias/eKatalog is the live source for the current execution of 61938: cage material, seal lip design and ratings can be revised between catalogue generations without any designation change.