SKF Cylindrical roller bearing caged Double row Series: NN

Product description
High-precision double row cylindrical roller bearings are produced by SKF as standard in the NN design and NNU design. These bearings can accommodate axial displacement of the shaft relative to the housing in both directions, within the bearing. They are separable, i.e. the bearing ring with integral flanges, together with the roller and cage assembly can be separated from the flangeless ring, to facilitate mounting and dismounting. They are available with either a cylindrical or a tapered bore (taper 1:12). In machine tool applications, cylindrical roller bearings with a tapered bore are preferred, because the taper enables more accurate adjustment of clearance or preload during installation.

NN design
The rollers of NN design cylindrical roller bearings are guided between integral flanges on the inner ring. The outer ring has no flanges. Therefore, the bearing can accommodate axial displacement of the shaft relative to the housing in both directions, within the bearing. NN design bearings can provide a unique balance between load carrying capacity, rigidity and speed and are therefore typically used as the non-tool end bearing in machine tool spindles. NNU design bearings, with a very low cross sectional height, provide a higher degree of stiffness than bearings in the NN 30 series. However, NN 30 series bearings can accommodate heavier loads. Boundary dimensions of NN design bearings are in accordance with ISO Dimension Series 30.