Nondestructive testing using ultrasonic sensor

Nondestructive testing (NDT) is the process of inspection or evaluating materials or component without destroying the functionality, serviceability and the structure of the testing product. Therefore, after the inspection is done the testing product can still be used as usual compared to the destructive testing that can cause the damage to the testing product. In the other word destructive testing has limitation because of the technique need a sampling product rather than on the materials is already put into the service. NDT are often used to determine the properties of the materials such as strengthen ductility, porosity and toughness. Todays, NDT are widely used in industries, manufacturing, and fabrication and in service inspection to ensure the quality of the product. Besides that, NDT also can reduce production cost by minimize the damage onto the product and also can reduce the production time by without damaging the testing product. Also in construction field, there are many benefits from NDT process toward this area such as to evaluate the strength of concrete. There are many method of NDT today such as Magnetic Particle Testing, Ultrasonic Testing, and Vibration Analysis. For testing of the building basically people are used the Ultrasonic Pulse Velocity (UPV) and Rebound Hammer. This paper is specifically discussed about the Nondestructive Testing (NDT) by using Ultrasonic

Simulation study on electrical resistance tomography using metal wall for bubble detection

Industrial process pipelines are mostly known to be constructed from metal which is a conducting material. Bubbles or gas detection are crucial in facilitating the bubble columns performance. By employing the Electrical Resistance Tomography (ERT) technique, a simulation study using COMSOL has been conducted to investigate the effect of excitation strategy, bubble sizes and locations towards the metal wall system. As for the current excitation strategy, conducting boundary protocol has to be applied when it comes to metallic vessel to overcome the grounding effect. Bubbles with a greater size than 2 mm and especially the one that is located near the wall boundary are much easier to detect. Further potential improvements to the current design and image reconstruction of the ERT system are desirable to improve the detection of small and centred bubble

Study and design of an ultrasonic flow tomographic front-end multi level measurement system

With the rapid evolution of electro-acoustical technology, ultrasonic tomography has made considerable progress in industry. An ultrasonic tomography system provides non-invasive and non-intrusive flow visualisation that enhances the understanding of fluid flow processes. The function of ultrasonic tomography is to continuously monitor the dynamics of liquid flow without interrupting the flow. The ultrasonic tomography technique is fully supported by a front-end hardware system. The front end is defined as all the hardware circuitries, including the ultrasonic transducer up to the Analogue-to-Digital Convertors (ADCs), even though the primary focus is the analogue signal processing components. We present here the challenges and trade-offs in the implementation of a front-end system by first explaining the basic operation of such a system, and then indicating what particular performance parameters are needed to ensure optimal system operation. Based on the results from our research studies, we propose an improved front-end multi-level solution that is more accurate than previous solutions and provides real-time measurement capability

A review of ultrasonic tomography for monitoring the corrosion of steel pipes

Infrastructure development is currently taking place rapidly. Designing a dwelling or premises is currently implemented quickly while controlling construction costs in addition to providing guidance on planned development. The architecture uses steel as a main part of the pile and drainage system is connected from sources to consumer. This study focuses on steel pipes that are exposed to corrosion. This problem is considered serious because steel pipes are used not only for the delivery of water supply but also for the delivery of gas and oil to the oil and gas sector, where the same problem occurs. Impacts of the problem of corrosion of steel pipes contribute to the risk of loss to the owner of the premises or industry. An overview of leakage problems, which cause a reduction in the volume of materials or hazards to the environment and consumers, is given, and the occurrence of corrosion in pipelines is evaluated. Monitoring methods use ultrasonic tomography as a major contribution to the implementation of monitoring and assessing the status of pipe durability and ability. This paper looks at the concept of diverse ultrasonic tomography inventions used to assist the process of monitoring of the level of pipeline capacity that will suffer corrosion

Simulation of electrode for dual-modality electrical resistance tomography and ultrasonic transmission tomography for imaging two-phase liquid and gas

Accurate multiphase flow measurement of gas/liquid, liquid/solid and liquid/liquid flow is still challenging for researchers in process tomography. The reconstructed images are poor particularly in the center area because of ill-posed inverse problems and limited of measurements data. Dual-modality tomography has been introduced to overcome the problem by means each modality is sensitive to specific properties of materials to be imaged. This paper proposed combination of ultrasonic transmission tomography (UTT) and electrical resistance tomography (ERT) for imaging two phase gas/liquid. In the proposed combination, detection ability in the medium of interest improved because two different images in the same space can be obtained simultaneously. This paper presents 3D numerical modeling approach using COMSOL software for ERT excitation strategy and electrode pre-designed geometry. Electrical resistance tomography (ERT) can be implemented for gas/liquid flow if the liquid is conductive. The objectives of this work is to analyze the optimum electrode dimension and shape in order to improve the situation of: (1) gas bubble detection located in the centre of the medium, (2) potential distribution and current density in a conductive medium, the developed numerical model simulated the changes in resistivity of the conductive material, with variations of electrode sizes, with opposite current excitation implemented into the region of interest. Simulation results show that the electrode size of 12 mm (w) × 40 mm (h) is suitable, which gives a good detection of center gas bubble with diameter 10mm in 100-mm-diameter acrylic vessel. Finally the findings are verified with Image reconstruction using Linear Back Projection (LBP) which gives good indication of the 10mm gas bubble

Hardware Development of Dual-Modality Tomography Using Electrical Resistance and Ultrasonic Transmission Tomography for Imaging Liquid and Gas

In decades, single-modality technique focuses on particular application such as liquid/gas, gas/solid, liquid/liquid and liquid/solid which has drawbacks in imaging complex flow with multiple components. This paper focuses on the development of dual-modality tomography system (DMT) integrating ultrasonic tomography and electrical resistance tomography (ERT) to visualize cross-sectional images of two-phase liquid/gas in vertical column. A combination of soft-field and hard-field tomography system measures different physical parameters of two-phase liquid/gas specific of two different material properties which are conductivity (σ) and acoustics impedance (Z). A DMT system is developed with 16 units of ultrasonic transceiver sensors, and 16 units of ERT electrode positioned alternately on a single-plane arrangement to perform measurement simultaneously. The reconstructed tomographic images obtained from measurement data from these two modalities are then fused into a single tomographic image by employing discrete wavelet transform (DWT)

Hardware Development of Dual-Modality Tomography Using Electrical Resistance and Ultrasonic Transmission Tomography for Imaging Liquid and Gas

In decades, single-modality technique focuses on particular application such as liquid/gas, gas/solid, liquid/liquid and liquid/solid which has drawbacks in imaging complex flow with multiple components. This paper focuses on the development of dual-modality tomography system (DMT) integrating ultrasonic tomography and electrical resistance tomography (ERT) to visualize cross-sectional images of two-phase liquid/gas in vertical column. A combination of soft-field and hard-field tomography system measures different physical parameters of two-phase liquid/gas specific of two different material properties which are conductivity (σ) and acoustics impedance (Z). A DMT system is developed with 16 units of ultrasonic transceiver sensors, and 16 units of ERT electrode positioned alternately on a single-plane arrangement to perform measurement simultaneously. The reconstructed tomographic images obtained from measurement data from these two modalities are then fused into a single tomographic image by employing discrete wavelet transform (DWT)

Application study on bubble detection in a metallic bubble column using electrical resistance tomography

Electrical resistance tomography (ERT) has been chosen as the field of study because of its advantages of being low cost, suitable for various kinds and sizes of pipes and vessels, having no radiation hazard, and being non-intrusive. In the development of ERT systems for metallic bubble column, prior knowledge of the fundamental process of the ERT system whilst improving the design and operation of the process equipment is essential. The fabricated electrodes need to be electrically insulated from the metal wall. Besides that, conducting boundary strategy is implemented to overcome the grounding effect of the metallic vesse

A review on the developments, potentials and challenges of application of metal products and in metal industry using process tomography system

This paper will provide an overall view of the developments, potentials and challenges of industrial applications involving metal products and in metal industry using process tomography system. The primary focus of the review is to highlight the differences occurred in process tomography in using metallic and non-metallic product especially involving the steel pipes which includes the differences in sensor arrangements (ERT, ECT, EIT), issues that arises in the use of metal and steel product besides in the metal production itself

Image reconstruction of metal pipe in electrical resistance tomography

This paper demonstrates a Linear Back Projection (LBP) algorithm based on the reconstruction of conductivity distributions to identify different sizes and locations of bubble phantoms in a metal pipe. Both forward and inverse problems are discussed. Reconstructed images of the phantoms under test conditions are presented. From the results, it was justified that the sensitivity maps of the conducting boundary strategy can be applied successfully in identifying the location for the phantom of interest using LBP algorithm. Additionally, the number and spatial distribution of the bubble phantoms can be clearly distinguished at any location in the pipeline. It was also shown that the reconstructed images agree well with the bubble phantoms