61808-ZZ-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 61808-ZZ-FAG model number is decoded

61808-ZZ carries two non-contact sheet-steel shields that hold the factory grease in and keep coarse debris out; they do not seal against liquids. Within the extra-thin 618xx section (diameter series 8 of ISO 15), multiplying bore code 08 by five gives the 40 mm bore; the 52 mm outside diameter and 7 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 40 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. Schaeffler HR 1 catalogue order number: 61808-2Z (FAG suffix 2Z), two non-contact steel shields, mapped here from the industry-neutral -ZZ spelling.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• A 40 mm shaft for 61808 should be finished to Ra ≤ 1.6 µm with square seating faces; at this bore a scored or oval journal shows up directly as running noise and early raceway damage.
• Only 6.0 mm of radial section separates bore and OD on the 618xx series at 40 mm: ring flex from clamping or an oval housing bore transfers straight into raceway stress, so seat roundness matters more here than on a 6208.
• ZZ shields are non-contact: 61808-ZZ-FAG blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 61808-2RS for that.
• Shielded 61808-ZZ-FAG units are typically greased for life; prying the shields out for regreasing usually bends them and leaves a gap that throws grease in service.
• A 40 mm bore listing showing the right d/D/B but no standard or precision-class reference may be a loose-tolerance import; measure bore/OD spread before fitting it to a machined shaft.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 7 mm-wide ring of 61808-ZZ-FAG drags the lip and overheats it.
• Schaeffler HR 1 lists the shielded version as 61808-2Z — FAG suffix 2Z, two non-contact steel shields. The industry-neutral page spelling is -ZZ; quote the FAG order number when buying through a Schaeffler channel.
• FAG rates 61808 at 16400 r/min mechanical limiting speed (thermal reference speed 8600 r/min) — electric-motor territory; prefer the open or 2Z execution (sealed 2RSR variants lose roughly a third of the thermal speed) and confirm grease life at the reference speed for continuous running.
• The 40 mm bore puts 61808 in Schaeffler's general-purpose industrial range; the standard cage and CN clearance cover most electric-motor and pump duty, and FAG's X-life generation of these sizes carries higher ratings than legacy HR 1 printings — check the current eKatalog listing before reordering.
• At 4.93 kN dynamic load rating (C) and 4.18 kN static (C0), 61808 is a light-load FAG bearing: L10 life above a few kN of equivalent load is short, so size up to a 62-series on the same bore if the duty sees shock or frequent starts.
• The 40×52×7 mm envelope of 61808 gives a D/d ratio of 1.30 and only 6.0 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 4.93/4.18 kN load ratings here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 61808-2Z on the 40×52×7 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61808 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 standard tolerance for this size is P0 (PN); P6/P5 precision executions exist for spindle-adjacent duty but carry different order numbers in the Schaeffler system — they are not a selectable sorting of standard stock.
• For hot shafts above roughly 100 °C continuous, consult Schaeffler about seal material and grease options for the 2RSR execution of 61808; the standard NBR lip is the economical general-duty choice, not the high-temperature one.