[srimanishreddy]

I have a Scenario where my lock nut is tightend using a prevailing torque of 14 Nm (as mentioned by the manufacturer) on to the rotor placed between bearings (But the tightening direction and the rotor rotating direction is same unfortunately). The lock nut is loosened after particular life cycle of usage as the rotor rotates with a acceleration of 1230 rad/sec and every time it starts, the sudden acceleration loosens the lock nut. Is there a simple approch to calculate a appropriate prevailing torque for this situation, so that the lock nut does not loosen up when the rotor starts accelerating towards it's max RPM of 9400 in 1 second?

[Jim Dawson]

I think there is more going on here than just the acceleration torque on the nut. My best guess that there is some relative movement between the rotor and the nut under high acceleration and that is what is causing the nut to loosen over repeated cycles. My solution would be to apply some 271 Loctite to the nut. This may not solve all of the problems however.

I suspect that the rotor is loosening on the shaft, and that is where the real problem is starting.