SKF 61801-2Z Metal Shielded Single Row Deep Groove Ball Bearing 12x21x5mm

The SKF 61801-2Z shielded deep groove ball bearing is engineered for applications where bearing space and weight are critical. Its 12mm bore, 21mm outside diameter and 5mm width provide a particularly slim cross-section, making it appropriate for narrow housings and lightweight rotating assemblies. Compared with the 61901 series, which measures 12 x 24 x 6mm, the 61801 offers a smaller radial and axial footprint where loads allow. Its single row deep groove raceways accommodate radial loads and limited axial forces in either direction. SKF specifies a basic dynamic load rating of 1.74kN and a basic static load rating of 0.915kN. These relatively modest ratings should be considered carefully when calculating bearing life or assessing shock loads.

The 2Z suffix identifies steel shields fitted on both sides. These non-contact shields help retain the factory-applied grease while reducing the entry of larger contaminants, with less friction than contacting rubber seals. SKF lists a 36,000rpm limiting speed and a 70,000rpm reference speed for this shielded configuration; these are different catalogue measures and should not be treated as interchangeable operating limits. The bearing has normal (CN) radial internal clearance, a sheet steel cage and an approximate mass of 6.3g. For exposed, wet or heavily contaminated environments, a contact-sealed alternative may offer more suitable protection, subject to its lower speed limits. When replacing the bearing, confirm the full 61801-2Z designation and ensure mounting loads are applied to the ring being fitted.

Typical Applications:

Precision measuring instruments and compact mechanisms

Miniature electric motors in clean environments

Light-duty robotics and automation assemblies

Compact guide rollers and positioning systems

Small mechanical drives with restricted bearing space