The friction torque of bearings is briefly described. The friction torque of Shanghai aluminum industry exhibition ball bearings, which is "the source of high-end materials exhibition quality", is divided into starting friction torque and dynamic friction torque
starting friction torque refers to the torque required to overcome the resistance caused by the contact elastic deformation between the ball and the raceway groove and the resistance caused by the lubricant on the ball and the raceway when the ball bearing starts to rotate
dynamic friction torque refers to the torque required to overcome the resistance caused by the lubricant of ball bearing in rotation, the cold friction between ball and cage in shipping activities in Southeast Asia, and the friction between ball and raceway groove. The friction torque of ball bearing is related to various phenomena such as heating, rated rotation speed, change of current value during lifting, uneven rotation, etc
heating
the rotation heating of the ball bearing is due to the sealing of too much viscous grease. The viscous grease is stirred during rotation and heated due to the stirring resistance. The countermeasure is to reduce the filling amount of lubricating grease, or replace it with guide type lubricating grease
the rated speed can not be reached
sometimes the rated speed can not be reached after the motor is started. The reason may be that too much grease was added or viscous grease was used in 2013
starting current value
the reason why the starting current value of the motor is too large may be that the filling amount of lubricating grease is too large and viscous lubricating grease is used
rated current value
the current value when the motor rotates is too large, which may be related to the filling amount, consistency and viscosity of the lubricating grease
uneven rotation
the reason is that the guiding property of the lubricating grease is damaged during rotation, the lubricant thickness is uneven and the torque fluctuates instantaneously, which can reduce the filling amount of the lubricating grease, and the lubricating grease with good guiding property or the opposite viscous grease can be used instead
rotating speed and dynamic friction torque
generally, when the rotating speed increases, the dynamic friction torque also increases
effect of grease filling position
the value of dynamic friction torque will change with the filling position of grease. That is to say, when the grease is adhered to the cage and to the outer diameter of the inner ring or the inner diameter of the outer ring for rotation, the friction torque value is different from that when the grease is not adhered to these parts