ULTRASONIC TESTING TECHNIQUE FOR SMALL-CALIBER PIPING CONTAINING DEFECTS

An effective method of ultrasonic testing was developed for inspecting the quality of weld seams for small-calibre, thin-walled pipes. The b asic technical problems encountered in measuring the height of defects in the piping by an ultrasonic testing method were analyzed and studi ed experimentally. To overcome these problems, two small probes with s pecial cylindrical contact surfaces, and five types of piping contrast specimens were machined, and a corresponding quantitative scaling met hod was developed. Some preliminary data obtained by the proposed meth od and a practical measurement method were presented. These results sh ow that the proposed method is also effective in determining the shape of defects in welded steel pipes, and has been directly used in the s tructural integrity assessment of pressure vessels and piping containi ng weld defects in a petrochemicals plant. Copyright (C) 1996 Elsevier Science Ltd.