Studies in the field of environmental epidemiology indicate that for the adverse effect of inhaled particles not only particle mass is crucial but also particle size is. Ultrafine particles with diameters below 100 nm are of special interest since these particles have high surface area to mass ratio and have properties which differ from those of larger particles. In this paper, particle size di...

The present study shows the relationship between welding quality and optical-acoustic emissions from electric arcs, during welding runs, in the GMAW-S process. Bead on plate welding tests was carried out with pre-set parameters chosen from manufacturing standards. During the welding runs interferences were induced on the welding path using paint, grease or gas faults. In each welding run arc vo...

A welding head is under development with integrated sensory systems for robotic laser welding applications. Robotic laser welding requires sensory systems that are capable to accurately guide the welding head over a seam in three-dimensional space and provide information about the welding process as well as the quality of the welding result. In this paper the focus is on seam tracking. It is di...

Introduction. The article discusses the improved repair technologies of pipeline material saturated with hydrogen sulfide, which should replace conventional methods that ignore operational features in a sulfide environment. aim this work is to develop technology for repairing pipelines operated environment by manual arc welding using consumable electrode. Materials and methods. Full-scale exper...

This study aims to calculate the resistance spot welding current digitally at a fast speed. The conventional open-loop spot welding machine cannot measure the current, thus the welding quality varies. The welding time of spot welder is very short, but the welding current is strong and it is hard to be measured, thereby resulting in the uncontrollability of welding quality. This study uses a hig...

The main objective of industries reveal with manufacturing better quality product at low cost and increase productivity. TIG welding is most vital and common operation use for joining of two similar or dissimilar parts with heating the material or applying the pressure by using the filler material for increasing productivity with less time and cost constrain. The TIG welding parameters are the ...

Installation of new pipelines is predicted to grow at a rapid rate over the next twenty years, due in part to the increase use worldwide of combined cycle power generation plant using natural gas a fuel. The need to construct large diameter pipelines over long distances has led to an increased demand to improve the productivity of pipeline girth welding. Many novel techniques have been tried in...

OBJECTIVES To study the airway response and its mechanism to welding fumes in six welders with respiratory symptoms. METHODS Methacholine and welding challenge tests were carried out. The concentration of welding fumes during the exposure test was measured. On two subjects who developed bronchoconstricition to welding challenge, additional tests were carried out including prick, patch, and in...