Development of Automatic Ultrasonic testing Method Using Super High Speed Zigzag Scanning Technique

摘要

We developed a high speed automatic ultrasonic inspection system for gasrnpipeline girth welds where newly developed angle beam array probes werernused. The system consists of the array probes, a light weight mechanicalrnscanner, a flaw detector and the signal processor. The array probe in whichrn32 transducer elements are arrayed 2mm apart from each other scansrnelectrically ultrasonic beam in the direction parallel to the weld. Inrncombination with mechanical scanning, the system with two array probesrninspects the whole volume of weld of a pipe 762mm in diameter and 19 mm inrnthickness within 2 minutes. The inspection time was 10 times shorter thanrnthat of the conventional probe system. The array probe system had the samerndetectability as that of conventional angle beam probe system.