蒸汽管道对接焊缝超声检测“山字波”研究

Study on Moutain Wave during Ultrasonic Testing of Steam Pipeline Butt Weld

在大型火力发电厂蒸汽管道对接焊缝的超声检测中,荧光屏上经常会出现“山字波”,当探头平行于焊缝移动时,“山字波”的信号在很大范围内都存在,且幅值很高,往往超过判废线。“山字波”的出现会增大缺陷波的识别难度,使得检测人员难以做出准确判断。通过采集主蒸汽管道对接焊缝“山字波”的静态波形,研究分析了“山字波”的产生原理,有助于在焊缝探伤时对“山字波”分析判断。

During ultrasonic inspection of butt weld in large thermal power plant steam pipe, the moutain wave often appeas on the screen. When the probe moves parallel to the weld, the signal of moutain wave exists in a large range, and the amplitude is very high which is higher than the rejection line. The appearance of moutain wave increases the difficulty of identifying the defect wave, which makes it difficult to make accurate judgments. By collecting the static waveforms of moutain wave of the main steam pipe butt weld, the formation principle of moutain wave was studied, which was helpful to analyze and judge the mountain wave in the weld crack detection.