SF040AR0 bearings ( 4 inch x 5.5 inch x 0.75 inch) have the advantages of Extremely compact, lightweight design, composite load-bearing capacity, high rigidity, and flexible installation, and are therefore widely used in the Robot joints, aerospace, semiconductor equipment, medical instruments and optoelectronic turntables.

| Part Number | SF040AR0 |
| Bearing Type | Inch Open Type A Angular Contact Ball Bearings |
| Equivalent | KAYDON KDN.KF040AR0 SILVERTHIN SF040AR0 SKF FPAF400 FAG L15VA400 NSK NBA10119 INA CSEF040 SSB RF040AR0 NTN KYF040 |
| Interchangeable | SILVER THIN SF040AR0 |
| Cage | Brass; one piece pocket separator |
| Series | SF SERIES 3/4" X 3/4" |
| Balls | standard 3/8" balls |
| Race Width Tolerance | +0.000 -0.005" |
| Contact angle [°] | 30 |
| Seal type | Open (No seal) |
| Units | Inch |
| Precision Class | ISO Class NORMAL / ABEC-1 |
| Rows NO. | One |
| B φ Inside [inch] | 4 |
| D Φ Outside [inch] | 5.5 |
| Width [inch] | 0.75 |
| L1 [inch] | 4.555 |
| L2 [inch] | 4.945 |
| L3 [inch] | 5.115 |
| (Note 2) max | 0.080" |
| RADIAL DYNAMIC [lbf] | 3735 |
| RADIAL STATIC [lbf] | 6350 |
| THRUST DYNAMIC [lbf] | 8419 |
| THRUST STATIC [lbf] | 18338 |
| APPROX WEIGHT [lb] | 1.9 |
The SF040AR0 Thin-section angular contact ball bearings mainly consist of a thin-walled inner ring, a thin-walled outer ring, steel balls, and a cage. Their cross-sectional dimensions are constant and extremely thin, with contact angles typically of 15°, 25°, or 30°, making them suitable for space-constrained installations.
Thin-section angular contact ball bearings utilize a thin-walled, constant cross-section design, resulting in lightweight construction and a small footprint, effectively reducing the overall weight of equipment. They can simultaneously withstand radial and axial loads, possessing high rigidity, high-speed capability, and good positioning accuracy, and are easy to install.















