Ultrasound phased array (PA) imaging has been regarded as a safe replacement for radiographic inspection, even though they have different detectability depending on flaw types. There are innumerable demands for non-destructive testing on weld joints of various pipes which are indispensable to most of industrial structures. Diverse ultrasound testing has been used to detect flaws in welding join...

This paper describes a threefold method of testing the performance of an array-based ultrasonic tool for nondestructive testing of spot welds. The tool is described in its capabilities, use, and advantages over existing counterparts. Performance testing for and the results from carrying out the testing are described. The three performance testing methods include 1) the use of calibrated samples...

Ultrasonic inspection of dissimilar welds is still a challenge due to the different acoustic impedances across the interfaces between parent metals, welded, butter or cladded regions. Typically parent metals are fine grained carbon/ferritic/20MnMoNi55 steel, which show isotropic character. Whereas weld/butter/cladded metals are INCONEL/ austenitic steel, which exhibit anisotropic character, att...

In this paper, we present LEARN++, a new algorithm that allows existing classifiers to learn incrementally from new data without forgetting previously acquired knowledge. LEARN++ is based on generating multiple classifiers, each trained with a different subset of the training data and then combining them to form an ensemble of classifiers using weighted majority voting. The fundamental contribu...

A new model-based approach for ultrasonic phased-array testing of dissimilar welds based on the direct measurement of the wave speeds inside the real weld by using scanning laser vibrometry is presented. With this technique the interaction of different wave modes with the weld can be studied in detail leading to important consequences for the measuring set-up. Together with the geometry of the ...

In ultrasonic defectoscopy it is very difficult to detect flaw in materials with coarse-grain structure. The ultrasonic signals measured on these materials contain echoes which are very similar to fault echo. These echoes arise from grains which are contained in material. For detection of flaw various methods for suppressing of echoes from grains have to be used. In this work we used the method...

Nearly all manufactured products in the metal industry involve welding. The detection and correction of defects during welding improve the product reliability and quality, and prevent unexpected failures. Nonintrusive process control is critical for avoiding these defects. This paper investigates the detection of burn-through damage using noncontact, air-coupled ultrasonics, which can be adapte...

Ultrasonic impact treatment (UIT), which is a peening method, is usually used as a post-weld treatment in order to improve the fatigue strength of welded joints. In this study, fatigue tests were carried out on web-gusset welded joints treated by UIT and the results were compared with the fatigue lives of as-welded joints in order to examine the effects of UIT on the fatigue lives of welded joi...

Ultrasonic welding is a very promising technique for joining thermoplastic composite (TpC) components in aircraft primary structures [1, 2]. The potential introduction of new lightweight structures in civil aviation has been driving the change towards condition-based maintenance (CBM) as an alternative to the regular inspection interval approach [3]. In turn, CBM has been pushing forward the de...

IHI Southwest Technologies (ISwT) provided Reactor Coolant System, Hot and Cold Leg Nozzle examinations in accordance with MRP-139, “Materials Reliability Program: Primary System Piping Butt Weld Inspection and Evaluation Guideline,” at the Robinson Nuclear Plant. During this outage volumetric inspections were performed using ultrasonic examination techniques qualified to meet the requirements ...