Abstract: The present invention relates to a method for detecting temporally varying thermomechanical stresses and/or stress gradients over the wall thickness of metal bodies, in particular pipelines. In the method, the temperature on the outer surface of the body is measured in order to determine a temperature progression and stress progression therefrom. In addition, electromagnetic ultrasonic transducers are used at at least one measuring point on the outer surface in order to determine the progression of the stresses and/or stress gradients over time over the wall thickness of the body in conjunction with the result of the temperature measurement. The method allows the fatigue monitoring of pipelines even in the event of rapid stress changes.

Abstract: The present invention relates to a method for detecting temporally varying thermomechanical stresses and/or stress gradients over the wall thickness of metal bodies, in particular pipelines. In the method, the temperature on the outer surface of the body is measured in order to determine a temperature progression and stress progression therefrom. In addition, electromagnetic ultrasonic transducers are used at at least one measuring point on the outer surface in order to determine the progression of the stresses and/or stress gradients over time over the wall thickness of the body in conjunction with the result of the temperature measurement. The method allows the fatigue monitoring of pipelines even in the event of rapid stress changes.

Abstract: The present invention relates to methods for non-destructive quantitative determination of the internal microstresses of type II and/or III which are based on subtraction of the maximum values of the load stress dependency of the maximum Barkhausen noise amplitudes on a test piece before and after hardening of the test piece in specific thermal hardening states. The present invention hence enables independent determination of the internal microstress of type II or III, simultaneous and resolved determination of the internal microstresses of type II and III and also determination of the sum of both types of internal microstresses.