Ultrasonic Measurement of Pipe Thickness

Abstract

<p>The U.S. Navy requires periodic ultrasonic inspection (UT) of many of its piping systems. The inspections, which measure the wall thickness of the pipes, are performed to prevent failures due to corrosion[l], and to guide decisions regarding component life span/replacement. Often, the inspections are performed with digital thickness gages. These thickness gages perform their best when used on flat, smooth, parallel surfaces, and obviously, shipboard piping systems do not always meet these criteria. Typically, pipe diameters vary from less than one inch to greater than twelve inches. Many pipes have surface corrosion which can cause inaccurate measurements when using digital thickness gages. Additional measurement inaccuracies can result from pipes being in difficult to access locations. A case-in-point and motivation for this work is as follows</p>