CRA(耐腐蚀合金)复合材料海底管道内表面通常堆焊约3 mm厚的625不锈钢, 该海底管道环焊缝通常采用射线(RT）检测技术评估焊缝的焊接质量。由于RT检测效率较低, 安全风险较高, 极大地影响了CRA复合材料海底管道铺设效率。针对以上问题, 对全自动超声波(AUT)检测工艺进行研究, 主要通过综合运用低频纵波相控阵(PA)探头, 爬波探头、双晶纵波相控阵(TRL)探头以及超声衍射时差(TOFD)探头, 对制作的22个人工缺陷焊缝(共242个不同区域的人工缺陷）进行评价试验, 并与RT检测评价结论进行对比分析, 以评估该AUT检测工艺对CRA复合材料海底管道环焊缝各个区域缺陷的检出率。

The inner surface of the CRA composite subsea pipe is always overlaid by 3 mm stainless steel. RT is the normal inspection method of the girth weld. Due to the low efficiency and high risk of RT, the CRA pipe-laying efficiency will pull down. This essay makes a research of the AUT technique focusing on performing the evaluation test on the 22 defective welds (242 induced defects located in different area) by the combination of the low frequency LW PA probes, creep probes, TRL probes and TOFD probes, so as to evaluate the POD of individual area in the CRA girth weld.