小径管异种钢对接焊缝层间未熔合缺陷的检测方法

The Testing Method for Incomplete Inter-run Fusion in the Butt Welds between Small Diameter Tubes of Dissimilar Steel

按照TSG G0001—2012《锅炉安全技术监察规程》规定对接焊缝需进行射线检测,检测过程按照NB/T 47013.2—2015《承压设备无损检测第2部分:射线检测》标准进行椭圆成像或垂直成像。受射线检测透照方向的影响,检测层间未熔合类缺陷有困难。通过采用不同的超声检测方法进行理论和试验研究,研发出配合有曲率柔性楔块的带有轴向和周向相控阵探头的夹持装置,成功实现了层间未熔合类缺陷的检测,弥补了射线检测的局限性。

According to the TSG G0001-2012 Boiler Safety Technical Supervision Administration Regulation,the butt weld needed X-ray test.The test was generally carried out according to the NB/T 47013.2-2015 Nondestructive Testing of Pressure Equipment Section 2:X-ray test through X-ray elliptical imaging or vertical imaging to standards.Normally,such defect as the lack of inter-run fusion is difficult to detect as variation of in-coming directions of the X-ray.Through theoretical and testing study on different UT methods,a kind of clamping fixture for holding axial/circumferential phased array probes in combination with flexible wedges with curvature has been developed for detecting the defect of the lack of inter-run fusion,thus breaking through the limitation of X-ray test.