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An x-ray digital radiography (DR) system has been developed at the Gadjah Mada University Indonesia for earthenware inspection. The DR system was installed at the Handicraft Production Centre of Kasongan Village, District of Bantul, Yogyakarta Indonesia. It comprised of a medical purpose x-ray generator (75 kV, 20 mA), an imaging plate from a fluorescence screen encapsulated in a dark tube, a CCD camera that was coupled to the imaging plate, a video frame grabber to develop digital radiography image and a computer system along with associate software specifically developed for DR purpose. Some handicraft samples have been tested using the system and provided comparative benefits to the handicraft business. The image quality indicator shows that the system may be upgraded for advance performance. Quality inspection through this nondestructive testing facility was proposed in order to minimize the rejected handicraft that commonly occurred. This facility was expected to be used for raw handicraft examination prior to oven procedure.

Manufacturing processes such as hot bending can lead to micro-cracks and other surface defects in pipe structures and detecting them early is crucial for deployment of such structures as components in the power plant industry. Current Nondestructive Evaluation methods such as conventional bulk Ultrasonic Testing (UT), although effective, require that the pipes are cooled before inspection is carried out, leading to operation shut-down and thus online inspection tools are desirable. Ultrasonic guided waves can provide an attractive and cost-effective alternative in this context, as against custom-built specialized high-temperature UT probes. Guided waves can travel long distances in uncoated structures and thus regular probes can be deployed away from, and carry out rapid remote inspection of, the heated region. In the work reported here, experimental and numerical studies were conducted to evaluate the potential of Rayleigh waves (non-dispersive high-frequency guided surface waves) for the remote inspection of U-bent steel pipes with shallow surface defects. The bend region in the pipes, containing a rectangular notch-like defect is heated using a flash lamp. Experiments using a typical angle beam wedge transducer coupled to the pipe away from the heated zone show that the notch can be reliably detected for bend-region temperatures up to 1800 C. The curvature at the bend region does not seem to affect the results. Finite Element simulations are used to gain insight into the physics of the problem. Currently this method is being investigated for the inspection of bent pipes where the bend region may be heated to higher temperatures in the range of 5000 C.