A Microwave Measuring System for Detecting and Localizing Anomalies in Metallic Pipelines

Abstract

In this work, an innovative system for structural health monitoring of metallic pipes is presented. The proposed system relies on using the pipeline as a waveguide for the propagation of an electromagnetic (EM) signal. Possible anomalies in the pipe provoke the partial reflection of the propagating signal. Differently from previous works, in relation to the proposed application, the EM test signal is injected in the pipeline/waveguide through a coaxial/waveguide transition that is made on the surface of the pipe (rather than on a cross-section as generally done). In practical applications, this strategy would allow to connect more easily to operating, buried pipes. Additionally, because reflections caused by anomalies may be difficult to identify with adequate accuracy, the authors have developed a dedicated processing strategy for the analysis of the reflections caused by anomalies. More specifically, by analyzing the measured reflected signal and by correlating it to the ideal reflected signal, it is possible to improve the localization of anomalies along the pipe. The proposed system, along with the processing and operating strategies were validated through fullwave simulations and experimental tests carried out on a steel pipe in presence of intentionally-provoked anomalies.

Design of a simple side-incident TE11 mode microwave probe for nondestructive pipe inspection

“…Although a short pipe was used as the supporter of the coaxial cable in this study, the coaxial cable can be directly inserted into the main pipe for practical on-site monitoring applications, as suggested in [26]. Future studies can focus on investigating more specific applications of the TE 11 mode microwaves to the detection of pipe defects, such as detecting slits with tilted orientations and the circumferential positions of defects, such as pipe wall thinning.…”

“…In addition, given that another Transverse electromagnetic (TEM)-TM 01 mode convertor is required for feeding TM 01 mode microwaves, the measured signals contain the reflections of microwaves in both the TM 01 and TE 11 modes, thus increasing the difficulties in localizing defects. In [26], a side-incident TE 11 probe using the TEM-TE 11 conversion was reported to detect pipe wall thinning. However, this study only briefly demonstrated the structure of the probe without providing detailed discussions on the influence of probe dimensions on conversion and corresponding optimizations.…”

A Method for Extracting Debye Parameters as a Tool for Monitoring Watered and Contaminated Soils

“…Microwave reflectometry (MR) is a powerful tool employed in several fields of interest [ 23 ], ranging from biomedical applications [ 24 , 25 , 26 ], structural health monitoring [ 27 , 28 , 29 , 30 ], characterization of devices [ 31 ], soil moisture content monitoring [ 32 , 33 , 34 , 35 ] or for leak localization in underground pipes [ 36 , 37 , 38 , 39 ]. Typically, as reported in Figure 1 , a microwave reflectometry-based monitoring system consists of three major components [ 40 , 41 ]: a probe; the instrument for generating/receiving the electromagnetic (EM) signal; an elaboration unit to acquire and process the measured data. …”

Towards the development of a cyber-physical measurement system (CPMS): case study of a bioinspired soft growing robot for remote measurement and monitoring applications

“…The 4.0 Era is characterized by an innovative multidisciplinary approach which addresses technical challenges by seeking transverse solutions to both technological and methodological problems [1]- [8]. The most effective expression of the 4.0 paradigm is represented by cyber-physical systems (CPSs), i.e., smart systems that include engineered interacting networks of physical and computational components, able to monitor and control the physical environment [9]- [14].…”