聚乙烯电熔接头中金属丝成像规律的理论分析与试验研究

Investigation on the Imaging Law of Metal wire in Electrofusion Joint by Phased Array Ultrasonic Technique

摘要: 电熔接头中金属丝信号会对传统超声检测产生干扰, 采用超声相控阵技术及B扫描实时成像技术, 对嵌入式电阻丝电熔接头进行超声检测试验。在试验过程中发现几种金属丝成像的规律, 并根据超声检测的理论解释金属丝成像的规律。通过试验研究得出: 根据超声图像中金属丝的排列情况、金属丝的错位和金属丝与特征线的距离, 可间接反映电熔接头的焊接情况, 判断接头是否存在冷焊、过焊等缺陷。

Abstract: The metal wires in electrofusion(EF) joint of polyethylene(PE) pipes will interfere the ultrasonic wave, which makes it difficult to detect the EF joint with traditional ultrasonic testing method. The phased array ultrasonic focusing technique as well as B-scan real image technology is used for testing the discontinuities of Electro-fusion joint with the metal wires. the imaging law of the metal wires is explored in the testing, and analyzed in terms of ultrasonic theory. The result shows: the arrangement, dislocation of the metal wire in the ultrasonic image can be used to detect the cold welding and over welding in EF joints.