Search results
Results from the WOW.Com Content Network
Shielding gases fall into two categories—inert or semi-inert. Only two of the noble gases, helium and argon, are cost effective enough to be used in welding.These inert gases are used in gas tungsten arc welding, and also in gas metal arc welding for the welding of non-ferrous metals.
Another shielding gas mixture, argon-hydrogen, is used in the mechanized welding of light gauge stainless steel, but because hydrogen can cause porosity, its uses are limited. [31] Similarly, nitrogen can sometimes be added to argon to help stabilize the austenite in austenitic stainless steels and increase penetration when welding copper.
Unwanted gas is generally removed by flushing with an inert gas. Argon is generally used for this purpose but helium is an alternative depending on gas cost and availability. Nitrogen has been used as a purge gas but is unsuitable for some stainless steels. The most common way to remove gas from the weld zone is to flush it away with an inert ...
Spray transfer GMAW was the first metal transfer method used in GMAW, and well-suited to welding aluminium and stainless steel while employing an inert shielding gas. In this GMAW process, the weld electrode metal is rapidly passed along the stable electric arc from the electrode to the workpiece, essentially eliminating spatter and resulting ...
This type of FCAW was developed primarily for welding structural steels. In fact, since it uses both a flux-cored electrode and an external shielding gas, one might say that it is a combination of gas metal and FCAW. The most often used shielding gases are either straight carbon dioxide or argon carbon dioxide blends.
SMAW is often used to weld carbon steel, low and high alloy steel, stainless steel, cast iron, and ductile iron. While less popular for non-ferrous materials, it can be used on nickel and copper and their alloys and, in rare cases, on aluminium. The thickness of the material being welded is bounded on the low end primarily by the skill of the ...
Gas metal arc welding (GMAW), commonly called MIG (for metal/inert-gas), is a semi-automatic or automatic welding process with a continuously fed consumable wire acting as both electrode and filler metal, along with an inert or semi-inert shielding gas flowed around the wire to protect the weld site from contamination.
Shielding gases: Two inert gases or gas mixtures are employed. The orifice gas at lower pressure and flow rate forms the plasma arc. The pressure of the orifice gas is intentionally kept low to avoid weld metal turbulence, but this low pressure is not able to provide proper shielding of the weld pool. To have suitable shielding protection same ...