Review of existing and possible techniques for corrosion under insulation and wall thickness measurement in steel pressure containments

摘要

This paper gives a review of existing and potential NDT techniques for measurement of wall loss due to corrosion. It is primarily aimed at steel pressure containments, measured from outside the containment. Traditionally, and still mainly, this has been carried out by ultrasonics. However, the use of a wider range of techniques is being considered because of a desire to reduce costs on coating or insulation removal and replacement by carrying out NDT through or past the outer layers, or to examine larger parts of a plant at one time.