NNU4930MAW33 Timken bearing code cylindrical roller bearing 150x210x60mm

The cylindrical roller bearings NNU4930MAW33 has outer rings with solid ribs and lubrications grooves and holes on outer rings, one solid brass cage,used in cement grind mill.

 

Cylindrical roller bearings consist of an inner and outer ring, a roller-retaining cage, and a complement of controlledcontour cylindrical rollers. Depending on the type of bearing, either the inner or the outer ring has two roller-guiding ribs. The other ring is separable from the assembly and has one rib or none. The ring with two ribs axially locates the position of the roller assembly. The ground diameters of these ribs may be used to support the roller cage. One of the ribs may be used to carry light thrust loads when an opposing rib is provided.The decision as to which ring should be double ribbed is normally
determined by considering assembly and mounting procedures in the application.
Type NU has double-ribbed outer and straight inner rings. Type Nhas double-ribbed inner and straight outer rings. The use of either type at one position on a shaft is ideal for accommodating shaft expansion or contraction. The relative axial displacement of one ring to the other occurs with minimum friction while the bearing is rotating. These bearings may be used in two positions for shaft support if other means of axial location are provided. Type NJ has double-ribbed outer and single-ribbed inner rings. Type NF has double-ribbed inner and single-ribbed outer rings. Both types can support heavy radial loads, as well as light unidirectional thrust loads. The thrust load is transmitted between the diagonally opposed rib faces in a sliding action.
When limiting thrust conditions are approached, lubrication can become critical.   When thrust loads are very light, these bearings may be used in an opposed mounting to locate
the shaft. In such cases, shaft endplay should be adjusted at time of assembly.