There are various designs, series, variations, and sizes of cylindrical roller bearings. The main design differences lie in the number of roller columns and the design and materials of the inner/outer ring flanges and retainers.
Bearings can cope with the challenges of radial heavy loads and high-speed applications. Adapting to axial displacement (except for bearings with flanges on both the inner and outer rings), they provide high stiffness, low friction, and long service life.
Cylindrical roller bearings also offer sealed or split designs. In sealed bearings, the rollers are protected against contamination, water, and dust, retaining lubricant while eliminating contamination. This results in lower friction and longer service life. Split type bearings are mainly used for difficult to reach bearing configurations, such as crankshafts, which can simplify maintenance and replacement.
Double row cylindrical roller bearings:
Cylindrical inner hole: compact structure, high rigidity, high load-bearing capacity, and small deformation under load, suitable for applications such as machine tool spindle support that require high precision and rigidity.
Conical inner hole (bearing rear code plus K): In addition to the advantages of cylindrical inner hole double row cylindrical roller bearings, the conical inner hole can also play a role in adjusting the clearance slightly, simplify the positioning device structure, and facilitate installation and disassembly.
The commonly used double row cylindrical roller bearings include NN, NNU, NNF types, etc. The outer ring of NN type has no blocking edge, while the inner ring has blocking edges on both sides and a middle blocking edge in the middle, which allows for axial displacement in two directions between the shaft and the bearing seat; The NNU type outer ring has a blocking edge on both sides and a middle blocking edge in the middle, while the inner ring has no blocking edge. It can also allow displacement in two directions between the shaft and the bearing seat in the axial direction, which is suitable for use as a moving end bearing; The NNF type is a double row fully loaded cylindrical roller bearing, which is a structural type with a middle edge outer ring and two double edge inner rings. It can withstand large radial loads, axial loads, and overturning moments, and is commonly used as a fixed end bearing.