Ultrasonic phased arrays are a new technology that offers considerable potential for inspecting construction welds. Using electronic control of the beam, phased arrays can scan, sweep, steer and focus the ultrasound. Since welds typically produce defects of known character and orientation, phased arrays can be programmed to optimize weld inspections. These inspections include standard ASME-type...

During the last several years we have been investigating ultrasonic techniques for evaluating the quality of solid state weld interfaces [1 ,2]. Promising results have been obtained on a variety of different solid state welds by extracting features from the ultrasonic waveforms and applying pattern recognition algorithms to separate acceptable from unacceptable welds. In general, the primary di...

This paper presents a fully experimental study on melting, flow and weld strength development during ultrasonic welding of CF/PPS composites with integrated triangular energy directors. The main goal of this research was assessing whether the heating time to achieve maximum weld strength could be significantly reduced as compared to ultrasonic welding with flat energy directors. The main conclu...

PWR reactor vessel (RV) head has a number of penetration nozzles, including nozzles with thermal sleeve for control rod drive mechanisms (CRDM) and without thermal sleeve. These nozzles are typically made of nickel-based Alloy 600 or 690 and welded to the inside of the RPV head. Cracking has been reported in Alloy 600 nozzles and the J-weld regions. These nozzles are normally inspected by eddy ...

Ultrasonic testing (UT) is widely applied for the inspection to various plants and structures. However, in the application to the inspection of high attenuation materials such as austenitic weld joints and the inspection near the surface, the SNR (Signal-to-Noise Ratio) decreases and it makes it difficult to assess the testing results. To solve this issue, systems of a signal processing by the ...

Ultrasonic modelling and simulation are widely used in inspection qualification by industrial non-destructive test. Due to limitation of inspection conditions and radiation environment inside the nuclear power plant, it is useful to study the application of ultrasonic simulation technology to in-service inspection in nuclear power plant. Simulation can be used to demonstrate the inspection capa...

Ultrasonic array technique for assessing the integrity of the circumferential electron beam weld between the lid and walls of copper canisters is presented in the paper. The results of laboratory verification of the performance of the ultrasonic array system on real canister samples are presented. A method for suppression of grain noise scattered from the internal copper structure based on digi...

In ultrasonic metal welding, two metal sheets are joined by the application of high frequency ultrasonic vibrations (20 kHz) under moderate pressure in which the vibrations are applied parallel to the interface between the sheets. The high frequency relative motion between the sheets forms a solid–state weld through progressive shearing and plastic deformation between surface asperities that di...

Ultrasonic-assisted tungsten inert gas welding was carried out on a thin plate of 2195 Al-Li alloy, and the characteristics of the weld pores were analyzed in terms of their size and porosity. The effects of welding speed and ultrasonic power on the porosity and size of the pores were investigated. The pores were found to occur primarily adjacent to the surface of the weld. The porosity decreas...