61934-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 61934-FAG model number is decoded

61934 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 34 by five gives the 170 mm bore; the 230 mm outside diameter and 28 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 170 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

• At 170 mm bore the ring mass is significant: heat 61934 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
• The 619xx thin section (30.0 mm section height at 170 mm bore) trades load capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
• Storage matters for open bearings: 61934-FAG leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
• 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 61934 units.
• Deep-groove ball bearings tolerate only minutes of misalignment; if the 230 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 61934-FAG.
• Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
• The open 61934 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 3800 r/min for 61934 (thermal reference speed 3150 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 170 mm bore places 61934 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.
• At 109 kN dynamic load rating (C) and 114 kN static (C0), 61934 is a heavy-load FAG bearing for industrial gearboxes and large conveyors; Schaeffler expects a machined brass cage (suffix M) at this rating for shock duty, and C0 must be checked against mounting or lifting loads.
• At 2750 g (2.8 kg), 61934 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 170×230×28 mm envelope of 61934 gives a D/d ratio of 1.35 and only 30.0 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 109/114 kN load ratings, mass 2750 g here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 61934-FAG on the 170×230×28 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61934 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.
• FAG sealed units arrive greased for life with a lithium-soap fill; Schaeffler quotes a shelf life for greased bearings and recommends running stock first-in-first-out rather than re-greasing aged sealed units.
• Mixing old and new FAG generations of the same designation in one arrangement is dimensionally acceptable, but where ratings matter — preloaded or matched sets — order both positions from the same generation and lot.