Materials Science Forum, Vol.473-474, 361-368, 2005
Dimensions of lifetime management
The lifetime management of different engineering appliances, structures and structure elements is one of the important technical-economic problems of nowadays. The problem is basically appeared in technical, economic and political dimensions and the solution can be imagined according to many approaches: microstructural approach, application of new design conceptions and operational approaches (conventional methods, fitness for purpose, structural integrity, integrity management, risk management). The methods, applied in the different approaches have basically two types: engineering and fracture mechanical methods. The time of operation, the frequency data of fractures and the fracture causing failure statistics of the engineering structures having great importance shows, that the significance of cyclic loadings, fatigue and fatigue crack propagation is emphasized in general. The sketched possibilities are shown by two examples in this paper. One of them is the system of lifetime management for cyclic loaded structures having cracks or crack like defects; the other is the building-up and purport of the integrated management system for hydrocarbon transporting pipelines.
Keywords:lifetime;fitness for purpose;structural integrity;risk management;fatigue;fracture mechanics;case studies