Development and study of ultrasonic immersion testing system for industrial and metrological application

Abstract

Ultrasonic non-destructive testing (NDT) is one of the prominent field involving inspection to evaluate defects, cracks, deposition or fusion of welding materials and dimensional measurements of the test piece(s). Ultrasonic immersion scanning systems are useful for various industrial and metrological applications. The conventional immersion system uses a dedicated pulser receiver module for the excitation and detection of signal from transducer and a fast analog data acquisition card (DAQ) to acquire the raw data into computer. Rigorous digital signal processing and filtering is used to extract desired information from the raw data. In the present work, development of an ultrasonic immersion C-scan testing system, intended for industrial and metrological applications, is described. The developed system uses a commercial ultrasonic flaw detector (UFD) for the data acquisition rather than using pulser receiver and DAQ card to acquire ultrasonic information. The software for the same has been developed in Visual Basic .NET framework to control all five servo motor based axes of the ultrasonic immersion scanning tank. The developed software scans the sample automatically with parameters specified by the user. The parameters include echo amplitude, echo location, separation between two echoes, and ultrasonic attenuation. The developed software generates the data files that can later be used for further analysis using suitable data analysis software such as Origin or MS excel. The functionality of the developed system has been tested for the detection of flaws present in the material, testing for thickness variation and ultrasonic attenuation. The developed system is capable of detecting the location of defects within the resolution of ±0.01 mm. Ultrasonic transducer movement resolution of ±0.01 mm over the sample, results in to generation of a high quality image.