针对工艺管道对接焊缝的特点，对焊接方法、焊接位置及易产生的缺陷进行了分析。由于工艺管道对接焊缝壁厚范围大，多是直管与直管、直管与弯头、法兰、阀门等管件对接，采用单面焊接双面成型工艺，这种特殊结构型式和焊接工艺，使超声波检测只能进行单面双侧扫查或单面单侧扫查。为了提高缺陷的检出率，对不同规格、不同结构的焊缝在选择扫查面、探头数量、探头型号和探头尺寸时应有针对性。根部缺陷的判定对仪器扫描线调节精度提出了较高要求，对典型缺陷的回波特征进行了分析。通过以上分析和采取的措施，能有效提高工艺管道对接焊缝超声波检测的质量。

Considering the characteristics of the process piping butt weld, this article analyzes the welding methods, the welding positions and the defects which are easily produced. As the range of thickness of the process piping butt weld is large, furthermore, the joints are almost among pipe fittings, such as straight pipes, elbows, flanges and valves, so we choose one formation welding. Due to the special structure and welding craft, UT only conducts single-sided bilateral scanning or single-sided unilateral scanning; in order to raise the defect inspection rate, we should choose scanning surface, probe quantity, models and size for different scales and structures of welding joints with pertinence. It puts forward higher requirement for the linear adjustable accuracy of apparatus scanning to judge the root defect. We analyze the characteristics of the waves of typical defects. By the analysis and measures above, it improves the test quality of the process piping butt weld effectively.