某300MW电站再热热段取样管角焊缝的无损探伤

Fillet Welding NDT of Reheat End Sampling Tube for A 300 MW Power Plant

火力发电厂高温蒸汽管道支管的管座部分容易发生早期失效,在采用单晶斜探头在对某300 MW级电站锅炉再热热段取样管管座角焊缝进行超声波检测时发现,在其周向断续区域、2倍深度及以外均存在较大当量的反射波信号显示。为获得该反射波的更多信息,利用磁粉检测方法辅助检测,最终确定了该管座角焊缝存在裂纹缺陷。检测结果表明,增加磁粉检测方法,能有效确认二次波法超声检测时的缺陷波形显示。

The tube socket part of high - temperature steam pipe manifold for thermal power plant is prone to early failure, during the supersonic testing on the reheat end sampling tube socket fillet weld for a 300 MW power plant with the single crystal angle probe, it is found that a bigger equivalent of the reflected wave signal displayed in its circumferentially discontinuous regions ,2 -time depth and beyond. In order to get more information of the reflected wave, the magnetic detection is used to in- spect aided, and it is ultimately determined that there is crack in the tube socket fillet weld. The test result shows that increasing the magnetic detection can effectively confirm the defect waveform dis- play during the second wave supersonic detection.