QJ221 Four-Point Contact Ball Bearing (105x190x36mm)
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Bearing dimensions and basic technical information.
Manufacturer Ratings
Load-rating symbols are printed as each manufacturer writes them in its own catalogue, so the same quantity can carry a different symbol from brand to brand.
| Brand | Dynamic Load Rating | Static Load Rating | Fatigue Load Limit |
|---|---|---|---|
| NSK QJ221 | 239 kN | 435 kN | — |
| Schaeffler (FAG) QJ221-N2-MPA | 233 kN | 255 kN | 12 kN |
| NTN QJ221 | 218 kN | 400 kN | 14.2 kN |
Speed Ratings
Speed limits depend on sealing and lubrication, and definitions differ by manufacturer. Contact-sealed variants are normally greased for life and run slower. Always confirm the exact variant in the manufacturer's table.
| Brand | Grease open / shielded | Oil open | Reference | Limiting |
|---|---|---|---|---|
| NSK QJ221 | 2,600 r/min | 3,600 r/min | — | — |
| Schaeffler (FAG) QJ221-N2-MPA | — | — | 3,450 r/min | 6,200 r/min |
| NTN QJ221 | 2,700 r/min | 3,600 r/min | — | — |
References
- NSK — NSK Ltd., Rolling Bearings for Industrial Machinery, CAT. No. E1103, Tokyo, Japan, Jan. 2025.
- Schaeffler (FAG) — Schaeffler Technologies AG & Co. KG, Rolling Bearings, HR 1, Herzogenaurach, Germany, Feb. 2025.
- NTN — NTN Corporation, Ball and Roller Bearings, CAT. No. 2203-3E, Osaka, Japan, Sep. 2000.
About This Type
Four-point contact ball bearings carry axial load in both directions with a single, compact bearing — one bearing does the axial duty of a paired angular-contact set. They are typically used as pure axial bearings alongside a cylindrical roller bearing that carries the radial load, in gearboxes, compressors and slewing arrangements.
The split inner or outer ring creates the four contact points and gives high axial capacity in both directions, but radial capacity is limited: the bearing should not be used to carry significant radial load. When it runs as a pure thrust bearing next to a radial bearing, the housing fit must allow the outer ring to move radially, so that it carries no radial load — and many sizes come with locating notches (suffix N2) that prevent outer-ring rotation.
Check the fit arrangement before mounting: as a pure axial bearing the outer ring is given radial clearance in the housing, and a locating-notch version must seat its notch against the housing pin. The split ring is separable, so keep the components of one bearing together and observe the marked mounting direction.
Series note: The QJ2 series is the standard medium design of the four-point contact range.
Related Guides
Disclaimer: Data on this page is compiled from publicly available online sources for reference only, and not every model appears in a manufacturer's published catalog. Values may differ between sources and editions — always verify against the manufacturer's current documentation before design or purchase.Full disclaimer →