It is as important not to torque certain fixings as it is to torque those requiring it.  In principle, torque should be applied to fixings where a) two surfaces are in full contact over the full area, b) movement is not anticipated or desirable.  As movement may take place vertically between restraints, torque should not be applied at the fixing where such movement may take place.  Torque should not be used as a means of preventing loosening of nuts under vibration etc.  In such cases, locking nuts should be used.

The examples below are indicative of cases where torque is/is not to be applied.   The same principles apply for both sockets and cast-in channel.