Search results for " Ndt"
showing 9 items of 19 documents
Off-line scan path planning for robotic NDT
2018
This work presents computer-aided scan path generation for robotic non-destructive testing of complex shaped test-pieces. Off-line programmed scan path was used to robotically inspect an aluminium fixed leading edge skin panel of an aircraft wing by means of swept frequency eddy currents method. Eddy currents probe was deployed by means of a six-axis robotic arm KUKA KR5 arc. Reverse engineering of the test-piece was carried out to reconstruct CAD model of its surface. Positioning accuracy of the performed continuous scan was measured with a laser tracker in accordance with ISO 9283:1998 and is reported in the paper. The positional uncertainty of the NDT scan calculated as the standard devi…
On the Use of Two Emerging Laser-Based Flaw-Detection Techniques – Considerations and Practicalities
2023
The pursuit of non-contact techniques for detecting ultrasonic waves propagating on the surface of solids is stimulated by the possibility of gaining some advantages over conventional contact methods. Non-contact methods are becoming a milestone in performing non-destructive evaluation in several industrial fields, where hazardous environments, narrow spaces, high temperatures, and complex geometries are encountered. Such methods exploit photo-acoustic interactions between light and sound waves. This work compares two non-contact laser-based methods for detecting artificial flaws of different sizes in metallic specimens. It uses multi-signal homodyne interferometry and single beam deflectom…
Implementation of a fast and low cost IR-NDT technique by means of a Square Pulse modulated Lock-In Thermography
2012
This work describes the development of an IR-NDT procedure based on a lock-in signal treatment in the frequency domain to obtain phase-contrast defect signatures. Heat stimulation is obtained by periodically shattering a common low-power halogen lamp. The delivered heat is then modulated as a train of square waves with multi-frequency harmonic content. The proposed lock-in algorithm is able to selectively retrieve phase and amplitude information at various frequencies of the acquired temperature, acting also as a narrow band filter to improve defect-signature to noise ratio. The procedure is implemented and evaluated by means of low cost IR equipment to investigate artificially defected thi…
Robotic non-destructive inspection
2012
Automation of non-destructive testing (NDT) of engineering components and structures represents one of the strategic objectives of many industries. It enables increases in accuracy, precision and speed of inspection while reducing production time and associated labour costs in contrast to manual inspection. The use of robots can provide additional flexibility and autonomy to automated NDT. Automated robotic inspection can be beneficial in diverse industrial scenarios ranging from integration of NDT into the manufacturing process of components with very complex geometry, such as gears, to periodical in-service overhaul of large structures (for instance, in petrochemical and aerospace industr…
Computer-aided tool path generation for robotic Non-Destructive Inspection
2013
Compared to manual Non-Destructive Testing (NDT) for inspection of engineering components, automated robotic deployment of the same NDT techniques offers an increase in accuracy, precision and speed of inspection while reducing production time and associated labour costs. Traditionally, the robot tool path is either taught or programmed manually. Automation of NDT tool path generation, as presented in this paper, offers further significant time reduction, and an increase in the flexibility of inspection planning compared to manual robot teaching and programming. Moreover, such a solution helps to maintain a controlled probe orientation with respect to the scanned surface, and thus which can…
Thermal NDT of glass reinforced composite panels for naval applications by means of a linear infrared scanner
2009
The work describes the development and application of a low cost Thermal NDT set-up to investigate the influence of delamination defects on thick glass fibre reinforced composite laminates simulating typical hull monolithic GRP panels. Two active thermographic techniques have been implemented in particular: a pulsed thermography and a step heating scheme. A 12 mm thick cross-ply panel has been manufactured and delamination defects simulated in two different ways: by embedding patches of folded Teflon sheets, and by drilling flat bottomed back holes. A number of defects was then positioned at three different depths form the scanned surfaces, measuring ¼, ½ and ¾ of the laminate thickness. A …
Influence of seamless pipes wall thickness variation for the effectiveness of Automated Ultrasonic Testing
2015
Offshore pipelines construction is a technological challenge. Increasing water depth, harsh environments, engineering and commercial constraints are just some of the existing issues. Material selection therefore plays a key role and, for several applications, seamless pipes offer both the best technical and commercial compromise. Typically, NDT inspection of girth welds is carried out using the phased array based automated ultrasonic testing (AUT) zonal discrimination approach. AUT, compared to other techniques, guarantees a higher probability of detection of flaws and it also allows a really accurate assessment of the indications. However, since one of the peculiarities of this technique i…
Adapting robot paths for automated NDT of complex structures using ultrasonic alignment
2019
Automated inspection systems using industrial robots have been available for several years. The IntACom robot inspection system was developed at TWI Wales and utilizes phased array ultrasonic probes to inspect complex geometries, in particular aerospace composite components. To increase inspection speed and accuracy, off-line path planning is employed to define a series of robotic movements following the surface of a component. To minimize influences of refraction at the component interface and effects of anisotropy, the ultrasonic probe must be kept perpendicular to the surface throughout the inspection. Deviations between the actual component and computer model used for path-planning resu…