SKF Cylindrical roller bearing full complement Double row Series: NNF

Product description
Full complement bearings (without a cage) incorporate a maximum number of rollers and are therefore suitable for very heavy radial loads at moderate speeds. They are used to locate the shaft axially in one direction and eventually to accommodate axial displacement of the shaft relative to the housing in the opposite direction.

NNF design
NNF design bearings have a two-piece inner ring, held together by a retaining ring. The inner ring has three integral flanges and the outer ring has one integral central flange. The bearings are used to locate a shaft axially in both directions. The distance between the two rows of rollers enables these bearings to accommodate tilting moments. The outer ring of an NNF design bearing is 1 mm narrower than the inner ring. In applications with a rotating outer ring, there is no need for spacer rings between the inner ring and adjacent components. The outer ring has two snap ring grooves to simplify installation and save space axially, when the bearing is mounted in/on an adjacent component, e.g. in rope sheaves. The bearings have a contact PUR seal on both sides. Each seal is fitted in a recess on the inner ring shoulder. The seal lip exerts slight pressure against the outer ring raceway. The bearings are filled with a high-quality grease with good rust inhibiting properties.

Relubrication
For many application conditions, NNF design sealed bearings do not require relubrication and can be considered relubrication-free. However, if they operate in a moist or contaminated environment, or if speeds are moderate to high, relubrication may be necessary. The bearings can be relubricated via lubrication holes in both the inner and outer rings