Bearings of NN design are double row cylindrical roller bearing, have an inner ring with two ribs and an outer ring without ribs. This design allows an axial displacement in certain limits, of the shaft in relation to the housing. Therefore, NN series rolling bearings are used in non-locating bearing units. Also, the NN Series bearings have no virtually thrust capacity.

Double row cylindrical roller bearings NN series have a cylindrical inner bore and a conical inner bore (bearing rear code plus K). This type roller bearing has the advantages of compact structure, large rigidity, large bearing capacity, small deformation after load, etc., and is especially suitable for machine tool spindle support. The conical inner hole can also play a role of adjusting the play in a small amount, and can simplify the structure of the positioning device, and is convenient for installation and disassembly.

NN type bearings are designed to ISO/DIN specified interchangeable dimensions where available, and it’s available in same size range as single row product.

Application

Cylindrical roller bearings are used in applications where high radial loads are present such as in conveyer belts, traction motors, railway car axle boxes, and oilfield mud pumps, gear drives, crop shear, rolling mills, machine tools, among others.