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...

In the first European Community Respiratory Health Survey (ECRHS I), an excess asthma risk was associated with high exposure to gases and fumes, mineral and biological dusts. In a 9-year follow-up study (ECRHS II), the aim was to study if welding at work increases the risk of asthma symptoms, wheeze and chronic bronchitis symptoms. The study also aimed to identify specific welding risk factors....

Laser beam welding is becoming widely used in many industrial applications. This paper reviews recent research conducted on the performance, potential and problems of thick section butt joint laser welding. Common defects that occur in laser beam welding with high power laser welding are discussed and possible solutions proposed. Methods of welding process efficiency improvement are analyzed.

1 ATE-80212044©Asian-Transactions September 2012 Study the Effect of Welding Joint Location on the Fatigue Strength and Fatigue Life for Steel Weldment Dr.Ali Sadiq Yasir Kufa University / Faculty of Engineering Mechanical Engineering Department IRAQ E-mail:[email protected] / [email protected] Abstract: The welding process is one of the oldest joining processes between the ma...

Abstract The gas tungsten arc welding process is an uncertain nonlinear multivariable system. In order to control the welding process, the nonlinear dynamic relationship between the weld pool geometry reflecting the weld quality and the welding parameters must be developed. A three-dimensional numerical model is developed to investigate the dynamic characteristics of the weld pool geometry when...

Laser welding has been widely used in various industry fields. In order to further alter and broaden its applicability, a novel technology of laser welding under vacuum is introduced. The combination of high power laser and low ambient pressure provides an excellent welding performance and quality. In this paper, an overview on laser welding under vacuum is presented. It begins with a short int...

The visual recognition methods of texture feature of welding seam have the important significances to realize the automatic tracking of welding seam in the steps of subsequent welding and cover welding of multi-layer welding. Starting from the point of view of making full use of texture feature of welding seam image, the method research and algorithm design are respectively carried out on the 2...

–Friction stir welding is a solid state welding technology used for welding low melting point metals, such as Al, Mg and its alloys. Later welding was conducted on dissimilar metals which also produced a better defect free joint. Tool design and welding parameters contributes a major role for producing a better weld. Material flow and friction heat are the factors that the internal factor for t...