高钢级管道残余应力超声波法检测及小孔法验证

Residual stress measurement of high-grade steel pipeline via ultrasonic method and verification by small hole method

随着中国油气管网的逐渐形成,管道安全评估日益重要。基于此,对声弹性原理、超声法应力测量技术概况进行了简要回顾,并针对高钢级油气输送管道安全服役评价的需求,开发超声波法无损残余应力测量系统。同时,提出了近零校准应力试块技术:通过将零应力试块退火后线切割,进一步释放应力,可进行更加精准的零应力标定。并根据检测实际需要设计了弧面探头。利用上述系统开展X80管道的残余应力无损测量研究,并采用小孔法对其结果进行验证,证明其测试精度可靠、重复性好。研究结果可为油气管道应力在线测量提供技术手段,为管道运行、修复、评估提供一种有效的技术支持。

With the gradual formation of China’s oil and gas pipeline network, pipeline safety assessment is increasingly important. On this basis, the principle of acoustic elasticity and the ultrasonic stress measurement technology were briefly introduced. In order to meet the needs of the service safety evaluation of high-grade oil and gas pipelines, a non-destructive residual stress measuring system with ultrasonic method was developed. Besides, the near-zero stress calibration technology of test blocks was also developed, which is to linearly cut the annealed zero-stress test block for further stress release, so that the zero stress can be calibrated accurately. Further, curved probes were designed according to the actual requirements of inspection. The study on nondestructive residual stress measurement of X80 pipeline was carried out with the abovementioned system, and the results were verified with the small hole method, which indicate that the test accuracy is reliable and repeatable. Thus, the study provides a good technical means for online stress measurement of oil and gas pipelines, as well as an effective technical method for pipeline operation, repair and evaluation.