Weld overlay of piping was first used as a method to repair components of simple configurations which were known to contain cracking. An adequate ultrasonic examination of these geometries can be achieved by using a few conventional search units. Currently the application of pre-emptive weld overlays as a mitigation technique and/or to improve the examination surface condition for more complex ...

offshore pipelines are an effective tool for transportation of oil and gas which are usually assembled by the use of girth welds. since flaws may naturally exist at such welds, fracture assessment of girth welded offshore pipelines is substantial. current fracture assessment procedures like bs 7910 consider identical material properties for the weld and the base metals. however the strength dif...

Using the traditional magneto-optical detection methods, micro-weld defects parallel with magnetic field direction may be overlooked. In order to overcome this, a non-destructive testing method based on imaging under vertical combined (VCMF) is proposed. To demonstrate experimental results of weld excited by or (PCMF) are compared those fields (constant (CMF), alternating (AMF), and rotating (R...

Thick-walled X80 pipelines for oil and gas transportation are difficult to relocate due their large size. In the process of narrow-gap overhead welding, welding defects, such as bulges lack sidewall fusion, can appear easily. To avoid these defects improve quality thick-walled pipelines, GMAW method is adopted in this paper. The formation characteristics weld influence arc oscillation parameter...

In this paper, the microstructure analysis and performance research of dual laser beam welded 2060-T8/2099-T83 aluminum–lithium alloys were carried out. First, macroscopic morphology characteristics T-joint under different welding conditions observed. Then effect parameters pore defects on tensile fatigue properties weld out experimental results analyzed. It was found that heat input has a sign...

This paper introduces a novel method for the quality evaluation of resistance spot welds. The evaluation is based on computer vision methods, which allow nondestructive on-line real-time processing. The input of the system is the image of a weld imprint on a metal band which covers the electrodes against wear and soiling. In order to find the position of the resistance spot welds, we describe a...

This paper describes the development and evaluation of neural network-based systems for industrial welding process control and weld quality assessment. The developed systems utilize recurrent neural networks for process control and both recurrent networks and static networks for quality prediction. The first section describes a system capable of both welding process control and real-time weld q...

Presently, wrapping of the welds at the ends of stiffeners is not done to avoid the undercutting of the stiffener corners and the attendant weld repair. The fatigue performance of stiffeners with undercuts was evaluated in a factorial design fatigue experiment. Undercuts at the flange edge and filling of the stiffener cope with the fillet weld were also evaluated. The undercuts did not influenc...