An adaptive control based on fuzzy logic has been implemented for Gas Tungsten Arc Welding (GTAW). This adaptive controller eliminates the problems frequently experienced with traditional Automatic Voltage Control (AVC) systems, which do not adequately perform for all operational conditions because of the non-linear relationship between the arc voltage, current and arc length. This paper examin...

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...

Like all steel types, HSLA requires a definition and strict practical adherence to welding parameters in order to achieve the required weld quality. Different sources offer a varying array of welding parameters. Although their hierarchical importance can be disputed, their principal definition and practical adherence are prerequisites for the quality of welded joints 1,2 . The analysis of earli...

Observation of the weld pool provides an effective path to understand and control the welding process. Observation data also attribute to the validation of numerical models, which helps researchers to analyze and evaluate the welding process. Extensive research has been conducted to provide in situ monitoring of the weld pool. The arc sensor was one of the first few sensors that was adopted for...

Predicting and controlling residual stresses are critical issues in welding engineering. With advancements in computer technology, a numerical simulation technique can predict welding residual stress. To accurately simulate temperature and stress fields, the thermal cycle obtained from the finite element model must be in coincidence with an actual heat source. This study performed a Gaussian di...

Sensing plays a key role in automating and controlling welding processes. Although arc light sensing has advantages over through-the-arc sensing for arc length control and seam tracking, the current technology relies on experimental data and lacks theoretical foundation. To improve measurement accuracy, this work addresses the theoretical foundation for arc light sensing. A theoretical model ha...

This paper presents the results of a study aimed at establishing the temperature distribution during the welding of magnesium alloy sheets by Pulsed Current Gas Tungsten Arc Welding (PCGTAW) and Constant Current Gas Tungsten Arc Welding (CCGTAW) processes. Pulsing of the GTAW welding current influences the dimensions and solidification rate of the fused zone, it also reduces the weld pool volum...

Arc welding is a common unit operation in the construction industry, where frequent changes in location and welding position make it more difficult to control fume exposures than in industries where fixed locations are the norm. Welders may be exposed to a variety of toxic airborne contaminants including manganese (Mn) and hexavalent chromium (CrVI). Local exhaust ventilation (LEV) is a well-kn...

The various welding parameters such as welding speed, voltage and gas flow rate were varied on HSLA steel and the effects of these parameters on weld bead geometry such as penetration, width & height have been studied. Mathematical equations have been developed using factorial technique. And the result of various effects are shown in tables. (Numerical Values). INTRODUCTION Wide variety of stee...

The relationships between the acoustic signal and the modes of the welding pool such as no-keyhole (melt-in), keyhole and cutting in variable polarity plasma arc welding (VPPAW) are investigated. Welch power spectral density (PSD) estimate is used for preprocessing the sound data. A neural network (NN) is used to distinguish the keyhole mode from the cutting mode. The results show that the keyh...