Single row cylindrical roller bearings are usually only subjected to radial force. Compared with ball bearings of the same size, the radial bearing capacity is increased by 1.5-3 times, with good rigidity and impact resistance. It is especially suitable for shafts with rigid support, short shaft support, axial displacement caused by thermal elongation and machine accessories requiring separate bearings for installation and disassembly. It is mainly used for large motors, machine tool spindles, front and rear supporting shafts of engines, axle supports of passenger cars, diesel engine crankshafts, automobile and tractor gearboxes, etc