The Gas Metal Arc Welding Process is characterized by many important process outputs, all of which should be controlled to ensure consistent high performance joints. However, application of multivariable control methods is confounded by the strong physical coupling of typical outputs of bead shape and thermal properties. This coupling arises form he three dimensional thermal diffusion processes...

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Modelling of the arc in electric arc welding is significant to achieve a better process understanding, thus gain better weld quality and a more efficient production process. It requires knowing the conditions at the surfaces of the anode and cathode. These conditions are very difficult to set from measurements and should be calculated. This requires modelling the complex physics of the electrod...

The use of time-frequency entropy to quantitatively assess the stability of submerged arc welding process considering the distribution features of arc energy is reported in this paper. Time-frequency entropy is employed to calculate and analyze the stationary current signals, non-stationary current and voltage signals in the submerged arc welding process. It is obtained that time-frequency entr...

The design process for a fuel-cell-based inverter system for domestic use is discussed. The peculiar characteristics of the fuel cell stack energy source require the use of a battery for buffering. The fuel cell characteristics and the battery requirements for this application are discussed. A large number of different possible solutions are examined. The proposed solution uses an active filter...

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...

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...

OBJECTIVES The objective was to quantify the blue-light hazard from CO(2) arc welding of mild steel. METHODS The spectral radiance of arcs in CO(2) arc welding of mild steel was measured for solid and flux-cored wires at welding currents of 120-480 A. Effective blue-light radiance and the maximum acceptable exposure duration were calculated from the spectral radiance using their definitions i...

Distributed generation (DG) will play an important role in future power generation systems, especially in stand-alone applications. Three phase four-leg inverter is a well-known topology which can be used as an interface power converter for DGs. Thanks to the fourth leg to provide the neutral path, the four-leg inverter is able to supply balanced loads as well as unbalanced loads. In this paper...