The use of DCPD method for measurement of growth of cracks in large components at normal and elevated temperatures

The paper deals with problems of measurement of initiation and growth of cracks in pipes and in some full-scale models––the connection of pipes to pressure vessels during experiments at room and elevated temperatures. A modification of a direct current potential drop method was used to compensate influences of (i) non-uniform cross-section of pipes, (ii) complicated shape and (iii) high temperatures. It is shown that different temperatures are not a limiting factor. A comparison between measured and actual crack length and front in complicated specimens is presented, as well as results of the method of an evaluation of subcritical crack initiation in pipes and their connections.