针对常规超声检测技术较难检测高密度聚乙烯热熔焊缝的现状，使用相控阵超声检测技术（PAUT）和衍射时差法（TOFD）对热熔焊缝进行试验性检测。对3个含有预置缺欠管件进行检测和对比，发现两种方法均能够检出预置缺欠，并能对缺欠进行准确定位。两种方法的检测数据均可记录存储，至少能够形成A/B视图，显示直观，便于缺欠定量和定性，为热熔焊缝无损检测提供了新的技术选择。

Aiming at the difficulty of conventional ultrasonic testing for HDPE hot-melt weld, phased array ultrasound (PAUT) and diffraction time difference (TOFD) were used to test the hot-melt weld. Through the detection and comparison of three pipe fittings with preset deficiencies, both methods can detect and locate the preset deficiencies accurately. The two methods can record and store the detection data, at least form A/B view, display intuitively, and facilitate the quantitative and qualitative evaluation of defects. It provides a new technical choice for nondestructive testing of hot-melt welds.