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Full-Text Articles in Engineering
New Approaches To Controlling Unstable Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
New Approaches To Controlling Unstable Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
Dominic Cuiuri
This paper describes recent developments at the University of Wollongong in the application of novel control strategies to improve the control of inherently unstable transfer in the GMAW process. The paper reviews the problems involved in maintaining arc stability with CO2 shielded arcs and proposes potential solutions based on the development of a new process control technique. Results of early investigations into the phenomena are reported.
Novel Control Techniques For Co2 Shielded Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
Novel Control Techniques For Co2 Shielded Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
Dominic Cuiuri
The control strategies that have been developed over the past four decades to control the inherently unstable metal transfer in the CO2-shielded GMAW process are described. The fundamental reasons for poor arc stability with CO2 as a shielding gas are discussed. From an understanding of the process behaviour, a new process control technique is proposed, and the future direction of research in this area is discussed.
Miab Welding Of Oil And Gas Pipelines, L. Fletcher, Gabriel Stecher, Cec Stubbs, John Norrish, Dominic Cuiuri, Jeffrey Moscrop
Miab Welding Of Oil And Gas Pipelines, L. Fletcher, Gabriel Stecher, Cec Stubbs, John Norrish, Dominic Cuiuri, Jeffrey Moscrop
Dominic Cuiuri
No abstract provided.
Influence Of Shielding Gas On Fume Formation Rate And Particle Size Distribution For Optimised Gmaw, Kristin Carpenter, Brian Monaghan, Alexander Nicholson, Dominic Cuiuri, John Norrish
Influence Of Shielding Gas On Fume Formation Rate And Particle Size Distribution For Optimised Gmaw, Kristin Carpenter, Brian Monaghan, Alexander Nicholson, Dominic Cuiuri, John Norrish
Dominic Cuiuri
The influence of shielding gas on fume formation rate (FFR) and particle size distribution has been investigated by using a technique developed for automatic control of the welding voltage in gas metal arc welding (GMAW). The results for automatic control are compared with the use of a fixed voltage. Significant reductions in FFR and a general decrease in average particle size were observed using the automatic control technique. This reduction in FFR was attributed to improved metal transfer stability, via a reduction in the occurrence of repelled globular transfer, by promoting the 'drop-spray' transfer condition, together with a reduction in …
Gas-Diffusion, Extractive, Biocatalytic And Electrochemical Membrane Biological Reactors, Oskar Modin, Faisal Hai, Long Nghiem, Angelo Basile, Kensuke Fukushi
Gas-Diffusion, Extractive, Biocatalytic And Electrochemical Membrane Biological Reactors, Oskar Modin, Faisal Hai, Long Nghiem, Angelo Basile, Kensuke Fukushi
Faisal I Hai
Several emerging technologies for treatment or resource recovery from wastewater are based on the combination of membranes and biochemical conversions. In this chapter, we review gas-diffusion, extractive, biocatalytic, and electrochemical membrane bioreactors (MBRs). Gas diffusion MBRs facilitate efficient delivery of a gaseous oxidant or reductant such as oxygen, hydrogen, or methane to microbial biofilms treating wastewater. Extractive MBRs completely separate the wastewater stream from the microbes and make toxic wastewaters amenable to biological treatment. Biocatalytic MBRs utilize enzymes or immobilized microbial cells for degradation of persistent xenobiotics or for synthesis of fine chemicals. Electrochemical MBRs make it possible to utilize …
Nonlinear Optical Spectrum Of Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction In Thz Frequency Regime, Yee Sin Ang, C Zhang, Qinjun Chen
Nonlinear Optical Spectrum Of Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction In Thz Frequency Regime, Yee Sin Ang, C Zhang, Qinjun Chen
Yee Sin Ang
We theoretically calculate the nonlinear optical spectrum of two-dimensional electron gas in the presence of Rashba spin-orbit interaction in terahertz frequency regime. For Rashba coupling parameter in the order of 0.4 eVÅ, the nonlinear optical response exceeds the linear response with the application of an external electric field strength in the order of 103 V/cm.
Tandem Gas Metal Arc Welding For Low Distortion Butt Welds, Nathan Larkin, Zengxi Pan, Stephen Van Duin, Mark Callaghan, Huijun Li, John Norrish
Tandem Gas Metal Arc Welding For Low Distortion Butt Welds, Nathan Larkin, Zengxi Pan, Stephen Van Duin, Mark Callaghan, Huijun Li, John Norrish
zengxi pan
The feasibility of using Tandem Gas Metal Arc Welding (T-GMAW) to produce full penetration butt welds in 5mm ship panel steel plates has been assessed and compared to the current Submerged Arc Welding (SAW) process. Experiments conducted show that the T-GMAW process is feasible and demonstrated a significant improvement over the SAW process in several areas including higher travel speed, a reduction in filler material, significantly lower post weld distortion, and a smaller Heat Affected Zone (HAZ), while maintaining similar microstructure and mechanical properties in the weld metal and HAZ.
Tandem Gas Metal Arc Welding For Low Distortion Butt Welds, Nathan Larkin, Zengxi Pan, Stephen Van Duin, Mark Callaghan, Huijun Li, John Norrish
Tandem Gas Metal Arc Welding For Low Distortion Butt Welds, Nathan Larkin, Zengxi Pan, Stephen Van Duin, Mark Callaghan, Huijun Li, John Norrish
Nathan Larkin
The feasibility of using Tandem Gas Metal Arc Welding (T-GMAW) to produce full penetration butt welds in 5mm ship panel steel plates has been assessed and compared to the current Submerged Arc Welding (SAW) process. Experiments conducted show that the T-GMAW process is feasible and demonstrated a significant improvement over the SAW process in several areas including higher travel speed, a reduction in filler material, significantly lower post weld distortion, and a smaller Heat Affected Zone (HAZ), while maintaining similar microstructure and mechanical properties in the weld metal and HAZ.
Treatment Of Coal Seam Gas Produced Water For Beneficial Use In Australia: A Review Of Best Practices, Long Nghiem, Ting Ren, Najdat Aziz, Ian Porter, Gyanendra Regmi
Treatment Of Coal Seam Gas Produced Water For Beneficial Use In Australia: A Review Of Best Practices, Long Nghiem, Ting Ren, Najdat Aziz, Ian Porter, Gyanendra Regmi
Long D Nghiem
There has been an exponential increase in both the production and exploration of coal seam gas (CSG) in Australia and many other regions in the world. A major issue associated with the production of CSG is the management of produced water. CSG is usually mixed with water in the coal seam, to recover the gas, the water must be first extracted from the coal seam to reduce pressure. This water — known as co-produced water or CSG water — is typically quite saline, large in volume and may contain heavy metals and other trace elements of concern. The management of …
Sorption Characteristic Of Coal, Particle Size, Gas Type And Time, Raul Maria Melgarejo Florentin, Najdat Aziz, Dennis Black, Long Nghiem
Sorption Characteristic Of Coal, Particle Size, Gas Type And Time, Raul Maria Melgarejo Florentin, Najdat Aziz, Dennis Black, Long Nghiem
Long D Nghiem
Sorption characteristics of Bulli seam coal samples were examined with respect to coal particle size, gas type and time. Sorption tests were carried out by the indirect gravimetric method for determining gas content in coal. Various coal particle sizes were tested in addition to 54 mm diameter coal core. The other coal sizes were ±15 mm (-5/8+0.530 mesh) cubical blocks and coal fragments of ±1.18 mm (-0.256+16 mesh), ±6.70 mm (-5/16+0.256 mesh), and ±8.00 mm (-5/8+5/16 mesh). The samples were maintained in specially designed pressure vessels, at constant temperature of 24 °C and subjected to gas pressures up to maximum …
Fusion Control In Dip Transfer Gas Metal Arc Welding, Gary Dean, John Norrish, Christopher Cook
Fusion Control In Dip Transfer Gas Metal Arc Welding, Gary Dean, John Norrish, Christopher Cook
Christopher Cook
No abstract provided.
Novel Control Techniques For Co2 Shielded Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
Novel Control Techniques For Co2 Shielded Gas Metal Arc Welding, Dominic Cuiuri, John Norrish, Christopher Cook
Christopher Cook
The control strategies that have been developed over the past four decades to control the inherently unstable metal transfer in the CO2-shielded GMAW process are described. The fundamental reasons for poor arc stability with CO2 as a shielding gas are discussed. From an understanding of the process behaviour, a new process control technique is proposed, and the future direction of research in this area is discussed.