6324-ZZ bearing: complete specifications & equivalents
The 6324-ZZ is a ISO 15 radial bearing sized 120 x 260 x 55 mm (bore x OD x width) with ZZ sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 120 mm |
| Outer diameter D | 260 mm |
| Width B | 55 mm |
| Material | GCr15 |
| Seal / shield | ZZ |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 208 kN |
| Basic static load rating C0 | 186 kN |
| Fatigue load limit Pu | 5.7 kN |
| Reference speed (thermal) | 5600 rpm |
| Limiting speed (mechanical) | 2800 rpm |
| Operating temperature | -30 to +120 °C |
| Mass | 12500 g |
| Manufacturer designation | SKF 6324-2Z |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-24 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); 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.
Dimensions in inches & 6300-series range
| Bore d | 4.724 in |
|---|---|
| Outer diameter D | 10.236 in |
| Width B | 2.165 in |
| ISO bore code | 24 |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in 6300-series | 10 mm |
| Largest outer diameter in 6300-series | 400 mm |
| Width range across 6300-series | 11–78 mm |
| Bore position in 6300-series (smallest first) | 24 of 30 |
| Bore above smallest 6300-series size | 110 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6324 | ISO 15 | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range. Brand-specific OEM equivalents pending multi-source data. |
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 6324-ZZ model number is decoded
In the 6300-series (ISO 15 diameter series 3) the last two digits encode the bore: 6324 carries bore code 24 = 120 mm. Outside diameter 260 mm and width 55 mm come from the ISO 15 boundary-dimensions general plan. Suffix -ZZ denotes two non-contact metallic shields; they retain grease and block coarse debris but are not liquid-tight. For normal-load mounting with a rotating inner ring on a 120 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- heavy conveyors
- pulp and paper machinery
- medium and heavy industrial drives
- large gearboxes
Known failure patterns
- fine-particle abrasion when non-contact shields let dust past in dirty duty
- grease aging in the shield-for-life cavity with no relubrication path
- electrical pitting in VFD-driven motors without grounding protection
- raceway smearing under marginal lubrication at start-up
Selection pitfalls — read before you substitute
- Mount this 120 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 63xx medium series gains rating at 120 mm bore through a 260 mm OD and 55 mm width; the heavier rolling elements also trade away some speed versus a 6224.
- ZZ shields are non-contact: 6324-ZZ blocks chips and coarse dust but is not waterproof — do not install it expecting a pressure-wash seal, step up to 6324-2RS for that.
- Shielded 6324-ZZ units are typically greased for life; prying the shields out for regreasing usually bends them and leaves a gap that throws grease in service.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 6324-C3. No clearance suffix means normal CN clearance.
- SKF spells the shielded version 6324-2Z (one shield: 6324-Z), not "-ZZ": the suffix language differs by brand even though the ISO envelope is identical, so quote the brand designation when ordering.
- The single-shield execution 6324-Z is a distinct order number in catalogue 17000: it suits open gears or oil-bath arrangements where the unshielded face faces the lubricant, and it is not interchangeable with the double-shield 6324-2Z for high-contamination positions.
- The 208/186 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 6324-ZZ bearing?
A 6324-ZZ deep-groove ball bearing has a 120 mm bore, 260 mm outer diameter and 55 mm width (4.724 × 10.236 × 2.165 in), per ISO 15 boundary dimensions. It is fitted with two non-contact metallic shields.
How does the 6324 bore code work?
The last two digits of 6324 are bore code 24, giving 24 × 5 = 120 mm bore. The 260 mm outside diameter and 55 mm width follow the ISO 15 diameter series, not the bore code alone.
What does the ZZ suffix on 6324-ZZ mean?
ZZ means two non-contact sheet-metal shields, one each side. They retain factory grease and block coarse particles with little friction, but do not seal against liquids, fine dust or pressure washing.
How does the 6300 compare with other series at the same 120 mm bore?
The '3' is the medium diameter series: 260×55 mm, 70.0 mm radial section at 120 mm bore, carrying more load than a 6224 but needing a larger housing bore and giving up some speed.
What is the SKF designation and catalogue data for 6324-ZZ?
In the SKF Rolling Bearings catalogue this size is listed as 6324-2Z — two non-contact sheet-metal shields, 120×260×55 mm per ISO 15. Quoted values: C 208 kN, C0 186 kN, Pu 5.7 kN, limiting speed 2800 r/min, mass 12500 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 6324-ZZ.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.