CORROSION INSPECTION ON PIPELINES WITH SH EAROGRAPHY

Pipelines can be inspected quickly and reliably on inner corrosion by means of laser shearography. During pressure change in the pipe shearo graphy measures all strain concentrations on the surface of the pipe. As corrosion leads to local wall thinnings inside the pipes these area s will expand more than non corroded areas and thus be indicated by sh earography from the outside of the pipe. In this paper important featu res and conditions are described for application of this technique for inspection in power plants. It is reported about experience on practi cal inspection tasks. Latest developments enable numerical data proces sing and graphical and coloured data presentation for easier defect re cognition.