焊管的偏析与超声检测研究

Research on Segregation and Ultrasonic Testing of Welded Pipe

针对焊管焊缝超声检测过程中,在热影响区的中心部位沿焊缝的长度方向出现的异常回波信号,且补焊返修后重新检测时回波仍然存在的问题,通过对该信号部位取样进行理化试验,找到了产生异常回波信号的原因。结果表明,焊缝熔合线及热影响区母材存在的偏析是产生异常回波出现的原因。分析了焊管偏析的种类和形成原因,对偏析回波信号的超声检测识别进行了分析研究,说明超声检测结合理化试验可以判断焊管严重偏析的存在。

During ultrasonic testing process of welded pipe weld, the abnormal echo signal appear in the center of HAZ along the length direction of the weld, and the signal still exist after repair welding. Through the physical and chemical test for the sampling signal part, it found the reason caused abnormal echo signal. The results showed that the segregation existed in weld fusion line and HAZ base metal is the reason caused abnormal echo signal. It analyzed the forming reason and type of welded pipe segregation, investigated the ultrasonic testing identification for segregation echo signal, and indicated that ultrasonic testing combining with the physical and chemical experiments can judge the existence of the welded pipe serious segregation.