AnzugsMoment

Anzugsmoment, or tightening torque, is the turning moment that is applied to a threaded fastener, such as a bolt or a nut, during assembly in order to create a clamping force (preload) in the joint. It is typically specified by the manufacturer and expressed in newton meters (Nm) or, less commonly, in other torque units. The chosen torque is intended to produce a defined preload that keeps the joint secure under operating conditions.

The relation between torque and preload is not direct or exact; it depends on friction in the threads and under the head, as well as the geometry of the fastener. A common practical form is T = K · F · d, where T is the applied torque, F is the preload, d is the nominal diameter, and K is a factor that reflects friction and contact conditions. Because friction varies with lubrication, surface finish, and cleanliness, identical torques can yield different preloads in different assemblies.

Lubrication and surface condition have a major influence: lubricated threads require less torque for the same preload, while dry or dirty threads require more torque and increase the risk of overloading the fastener. Consequently, torque values are specified for particular lubrication conditions and must be followed carefully. If precise preload is required, alternative methods such as torque-angle tightening or direct preload measurement (e.g., via bolt elongation) may be used.

In practice, anzuğsmoment is applied with a calibrated torque wrench, and tightening procedures often prescribe sequence, cleanliness, and sometimes locking methods (threadlockers, lock nuts) to ensure joint integrity. Improper torque—too low or too high—risks loosening or failure of the joint.