Being a life management tool, non-destructive testing is designed to detect defects in components before they become critical under load. Non-destructive testing has consequently become a well-established technique to ensure the safe and economic operation of pressurised components. However, life assessment and prediction requires knowledge about load conditions and history and material degradation along with a quantitative defect state evaluation. Safety and economics could be improved if non-destructive methods were able to control these problems. There are generally no practical non-destructive techniques for inspecting or monitoring pressurised components quantitatively for defect states, stress states, and possible material degradation as the result of creep, fatigue or embrittlement. This paper stresses the need for possible future non-destructive techniques which have already successfully demonstrated the potential of these new inspection objectives. The examples offered below outline the future use of non-destructive testing to evaluate defect states and control early material degradation by way of hardness measurements. These techniques can be integrated in life management software systems for the purpose of improving the reliability and economics of their application. (C) 1997 Published by Elsevier Science Ltd.
