Gas blending is the process of mixing gases for a specific purpose where the composition of the resulting mixture is specified and controlled. A wide range of applications include scientific and industrial processes, food production and storage and breathing gases.
Gas mixtures are usually specified in terms of molar gas fraction (which is closely approximated by volumetric gas fraction for many permanent gases): by percentage, parts per thousand or parts per million.
Volumetric gas fraction converts trivially to partial pressure ratio, following Dalton’s law of partial pressures. Partial pressure blending at constant temperature is computationally simple, and pressure measurement is relatively inexpensive, but maintaining constant temperature during pressure changes requires significant delays for temperature equalization. Blending by mass fraction is unaffected by temperature variation during the process, but requires accurate measurement of mass or weight, and calculation of constituent masses from the specified molar ratio.
Gas mixing systems may be mechanical, using conventional rotameter banks, or electronic, using proportional solenoids or pulsed injectors, and control may be manual or automatic.
Refer section on application
Peacock Blue with Aluminium / White band.
Peacock Blue with Black band.
Peacock Blue with Red band.
Peacock Blue with Aluminium / White and Black band.
The cylinders are available in various capacities e.g. 7 m3 capacity at 150 kg/cm2 and 12m3 capacity at 250 kg/cm2.
This has lower spatter and good weld penetration, suitable for thicker plates and steel significantly covered with mill scale.
Suitable for short circuit, globular, pulse and spray transfer welding. Maximum productivity for thin metals in short-circuiting mode; has lower tendency to burn through than higher-CO2 mixes and has suitably high deposition rates.
It is commonly used by hobbyists and in small-scale production. Limited to short circuit and globular transfer welding. Common for short-circuit gas metal arc welding of low Carbon steel.
It is used for short-circuiting and spray-transfer of Carbon steel.
It is used for spray arc on stainless steel, Carbon steels, and low alloy steels. The addition of 2% Oxygen encourages spray transfer, which is critical for spray-arc and pulsed spray-arc GMAW.
It is added to Argon in amounts typically fewer than 10% to prevent Hydrogen embrittlement. It can be added to Argon-Carbon dioxide blends to counteract the oxidizing effects of Carbon dioxide. Its addition narrows the arc and increases the arc temperature, leading to better weld penetration.
Required in welding