welding is an extremely complex process; however, due to its commercial importance, it is essential that a more thorough study of the various processes be undertaken. Three examples of areas requiring greater understanding of arc physics are presented. The first discusses heating or cooling of the metal at the cathode; the second describes variations in heat transfer using various shielding gas...

This paper presents a simplified model of cracked beam by single-degree-of-freedom system. Equivalence between the and SDOF models means that they have same fundamental natural frequency similar response functions (FRFs). Similarity FRFs is checked using frequency-domain assurance criterion acknowledged herein as spectral similarity index (SSI). Finally, both its been examined versus crack loca...

In the present study, the fumes generated from manual metal arc (MMA) and submerged metal arc (SMA) welding of low temperature service steel, and the chromium and nickel percentages in these fumes, were measured at various horizontal distances and vertical heights from the arc in order to obtain a three dimensional distribution. The MMA welding fume concentrations were significantly higher than...

Occupational asthma (OA) can be induced by fumes of manual metal-arc welding on stainless steel. In recent years, the use of special stainless steels (SSS) with high chromium content has increased. This study presents two cases of OA caused by manual metal-arc welding on SSS. In both cases, the diagnosis of OA was based on respiratory symptoms, occupational exposure and positive findings in the...

OBJECTIVES Ultraviolet radiation (UVR) emitted during arc welding frequently causes keratoconjunctivitis and erythema in the workplace. The degree of hazard from UVR exposure depends on the welding method and conditions. Therefore, it is important to identify the UVR levels present under various conditions. METHODS We experimentally evaluated the UVR levels emitted in gas metal arc welding (G...

Most previous welding simulations are based on a flat weld pool surface and become unmeaningful when the surface deformation is significant. In recent years, some researchers have developed numerical models capable of simulating free surface motion in welding processes, but they focus on the discussions of physical equations, boundary conditions, and solutions, rather than the numerical algorit...