Effect of alkaline additional agent in shielding gas on disperse composition of welding fume

Gas-shielded arc welding of stainless steels belongs to processes which are characterized by the highest concentration of chromium (VI) and nickel in welding fume. These substances are carcinogenic to humans. Material and technological conditions of gas-shielded arc welding of stainless steels influence fume emission rates and chemical composition of welding fume. This fact creates the possibility of process optimization in aspect of emission rates and chemical composition of welding fume including carcinogenic compounds. This paper presents the correlation between shielding gas compositions and fume emission rates and carcinogenic substances contents during gas-shielded arc welding of stainless steels using MIG/MAG, Cold Arc and CMT methods.

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Formation of Particles in Welding Fume Plasmas: Numerical Modeling and Experiment

Ukrainian Journal of Physics ◽

10.15407/ujpe64.5.392 ◽

2019 ◽

Vol 64 (5) ◽

pp. 392

Author(s):

V. I. Vishnyakov ◽

S. A. Kiro ◽

M. V. Oprya ◽

O. D. Chursina ◽

A. A. Ennan

Keyword(s):

Numerical Modeling ◽

Gas Metal Arc Welding ◽

Welding Fume ◽

Liquid Droplets ◽

Breathing Zone ◽

Shielding Gas ◽

Gas Temperature ◽

Gas Plasma ◽

Metal Arc Welding ◽

Primary Particles

Formation of particles in a fume plasma obtained from the gas metal arc welding is investigated by the numerical modeling of the plasma evolution. The model of welding fume plasma evolution includes the following processes: vapor emission from the arc zone and mixing with a shielding gas, plasma formation, nucleation, nucleus growth via the material condensation and coalescence, solidification of liquid droplets into primary particles, and coagulation of primary particles into inhalable particles in the breathing zone. The computed results are compared with experimental data on the specific surface area, chemical composition, and dependence of the particle sizes on the shielding gas temperature.

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Effect of shielding gas temperature on the welding fume particle formation: Theoretical model

Journal of Aerosol Science ◽

10.1016/j.jaerosci.2018.07.006 ◽

2018 ◽

Vol 124 ◽

pp. 112-121 ◽

Cited By ~ 4

Author(s):

V.I. Vishnyakov ◽

S.A. Kiro ◽

M.V. Oprya ◽

A.A. Ennan

Keyword(s):

Theoretical Model ◽

Particle Formation ◽

Welding Fume ◽

Shielding Gas ◽

Gas Temperature

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Alternatives for Joining Stainless Steel to Reduce Cr(VI) Emissions and Occupational Exposures

Journal of Ship Production and Design ◽

10.5957/jspd.2011.27.2.91 ◽

2011 ◽

Vol 27 (02) ◽

pp. 91-97

Author(s):

K. M. Paulson ◽

J. Wang ◽

N. Topham ◽

C. Y. Wu ◽

B. T. Alexandrov ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Stainless Steel ◽

Air Pollutants ◽

Occupational Exposures ◽

Welding Fume ◽

Oxygen Species ◽

Hazardous Air Pollutants ◽

Shielding Gas ◽

Welding Consumables ◽

Welding Stainless Steel

Welding stainless steel generates hazardous air pollutants (HAPs). Two technologies were developed to reduce these HAPs. The first, tetramethylsilane is added to the welding shielding gas, and welding proceeds as normal. Reactive oxygen species are consumed, and the resulting metal fume particles are encapsulated. In the second technique, new chromium-free welding consumables are introduced nearly eliminating Cr(VI) in the welding fume.

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