The Ultrasonic Testing of Micro-crack in P91/92 Steel Pipe Butt Weld

Due to the large number application of P91/P92 steel of thermal power generating units in domestic, weld defects detection problem also gradually became the focus of quality supervision work. In the process of operation maintenance, the defects detected by Ultrasonic inspection were mainly micro-cracks in the interlayer. In this paper,by means of ultrasonic inspection on the P91 steel butt weld of main steam pipe in a factory, the waveform character of micro-cracks was analyzed, and the way how to judge and identify the defects in ultrasonic testing was studied and discussed.