HUNDREDS OF THOUSANDS of people work in welding, cutting and brazing. It is estimated that welders compose 1 to 2% of the U.S. working population, including a significant segment of the aging workforce. According to OSHA’s Christine Petitti, the most commonly used welding processes are: 1) Flux-cored arc welding (FCAW). This process uses an arc between a continuous filler metal electrode and th...

Plasma arc cutting is used to cut any conductive material. It consists in blowing pressurized gas and feed current an arc, leading a thin plasma dart able melt down the material blow it away, creating kerf. Its quality depends on its shape. This paper shows, through experimental measurements, how inner geometry of torch can affect quality. appears that one side kerf much more oblique sensitive ...

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...

This paper deals with modeling of plasma cutting process using artificial neural network (ANN). The objective was to develop an ANN model in order to predict the ten-point height of irregularities (Rz) in terms of three input parameters, cutting current, plate thickness and cutting speed. To this aim, a feed-forward backpropagation ANN was developed and trained using the experimental data. Afte...

Arc ablation holds the promise of fast, low-cost metal removal at faster rates than laser, plasma and electron-beam methods and without the tooling and fixturing forces of conventional machining. Preliminary results show surface finishes in the tens of microns range at high material removal rates (MRRs) by adaptive control of arc voltage: up to 97 mm3/sec at 4 kW. These results far exceed the c...

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 are investigated. The Welch power spectral density (PSD) estimate and short-time Fourier transformation are implemented to analyse and identify the diVerent modes of the welding pool. The results show that the no-keyhole mode...