6307-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 6307-ZZ-FAG model number is decoded

6307-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 medium 63xx section (diameter series 3 of ISO 15), multiplying bore code 07 by five gives the 35 mm bore; the 80 mm outside diameter and 21 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 35 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: 6307-C-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

• Sizes around 35 mm bore are normally pressed on cold with a sleeve against the inner-ring face; the press force must never route through the outer ring or the balls of 6307-ZZ-FAG.
• The 63xx medium series gains rating at 35 mm bore through a 80 mm OD and 21 mm width; the heavier rolling elements also trade away some speed versus a 6207.
• ZZ shields are non-contact: 6307-ZZ-FAG blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 6307-2RS for that.
• Do not wash 6307-ZZ-FAG in solvent before mounting: the grease inside the shielded cavity is the service fill, and solvent creeping past the shield gap strips it out.
• The housing bore for the 80 mm OD should be round within IT7; an oval bore pinches the outer ring of 6307-ZZ-FAG and shows up later as two-point loaded raceway wear.
• Never mix components between two 6307-ZZ-FAG units: rings, cage and balls are factory-matched and are not field-interchangeable, even between identical designations.
• Schaeffler HR 1 lists the shielded version as 6307-C-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.
• At 11500 r/min mechanical limiting speed (thermal reference speed 10900 r/min), 6307 covers general-purpose motor and pump duty; keep grease fill at 25–35% of free volume and verify the housing can dissipate the frictional heat at the thermal reference speed.
• The 35 mm bore puts 6307 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.
• FAG rates 6307 at 37 kN dynamic (C) and 19.1 kN static (C0); this upper-medium rating covers conveyor and gearbox drives, but under shock the pressed steel cage can become the limiting element — consider the machined brass cage (suffix M) for impact duty.
• At 488 g, 6307 requires a soft-jaw vise or arbor press for mounting — never hammer it onto the shaft, and support the opposite ring to avoid brinelling the raceways.
• The 35×80×21 mm envelope of 6307 gives a D/d ratio of 2.29 and 22.5 mm radial section height — a heavy FAG section for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
• The 37/19.1 kN load ratings, mass 488 g here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 6307-C-2Z on the 35×80×21 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6307 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.
• For hot shafts above roughly 100 °C continuous, consult Schaeffler about seal material and grease options for the 2RSR execution of 6307; the standard NBR lip is the economical general-duty choice, not the high-temperature one.
• 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 6307 may quote higher values than the HR 1 print figures on this page — the envelope is identical either way.