There is a rapid trend in various industries to replace the metallic pipes by nonmetallic ones. This is due to the certain properties, such as high strength, lightweight, resilience to corrosion, and low cost of maintenance for nonmetallic pipes. Despite the abovementioned advantages, nonmetallic pipes are still affected by issues, such as erosion, defects, damages, cracks, holes, delamination, and changes in the thickness. These issues are typically caused due to the manufacturing process, type of carried fluid composition, and flow rate. If not examined well, these issues could lead to disastrous failures caused by leakages and bursting of the pipes. To prevent such major failures, it is extremely important to test the pipes periodically for an accurate estimation of their thickness profile. In this article, we propose a nondestructive testing (NDT) technique, based on near-field microwave holography, for identifying the fluid carried by a nonmetallic pipe and estimating the pipe’s thickness profile. Identifying the carried fluid helps improve the thickness profile estimation. The performance of the proposed techniques will be demonstrated via simulations and experiments.

中文翻译：

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流体输送非金属管道的定量缺陷尺寸评估

非金属管材替代金属管材在各行各业呈现快速发展趋势。这是由于非金属管道的某些特性，例如高强度、重量轻、耐腐蚀和维护成本低。尽管具有上述优点，但非金属管道仍然受到侵蚀、缺陷、损坏、裂纹、孔洞、分层和厚度变化等问题的影响。这些问题通常是由于制造过程、携带的流体成分的类型和流速造成的。如果不仔细检查，这些问题可能会导致管道泄漏和爆裂造成灾难性故障。为了防止此类重大故障，定期测试管道以准确估计其厚度分布非常重要。在本文中，我们提出了一种基于近场微波全息术的无损检测 (NDT) 技术，用于识别非金属管道携带的流体并估计管道的厚度分布。识别携带的流体有助于改进厚度分布估计。所提出的技术的性能将通过模拟和实验来证明。