Who does not yearn for that shiny custom made modular kitchen or that bar counter? The metal of choice is stainless steel as it does not rust or corrode (because of high chromium content). Importantly, it is easily cleanable and therefore, hygienic.
Being able to weld stainless steel not only looks great on your portfolio, but is a great skill, and is very difficult. It makes you valuable as some stainless steel welding jobs require competent welders. It is not the most straightforward metal to work. Stainless steel is of many compositions. Austenitic SS, Ferritic SS and so on but this is of academic interest here.
Methods Employed In Stainless Steel Welding
There are three basic methods of welding stainless steel.
Resistance Or Spot Welding
Spot welding is the most economical method of welding. The resistance welding equipment is extremely versatile and is suitable for both small and large projects. Resistance welding uses an electric current to heat frayed edges, and so fuse them. It is highly productive on metals with a low melting point, such as stainless steel. The process can be adapted to prevent the warping of the metal.
Metal Inert Gas Or Gas Metal AC Welding
This process is semi-automatic incidentally, that when performed accurately results in a robust cohesive bond between two plates of SS. An argon abundant shielding gas along with a solid wire electrode is in use for this method. It is sought after as it allows the welder to use a pulsed current supply which makes it trouble-free to reach out=of-the-way locations on complex steel projects. For arc stability and improved weld quality, helium, oxygen and carbon dioxide are mixed in.
Tungsten Inert Gas System Or Gas Tungsten Arc Welding
This method, above all, is the most commonly in use procedure for welding stainless steel and is high quality, flexible and durability. The heat input is low, and therefore it is excellent for low gauge, thin materials. The argon gas is mixed sometimes with helium, hydrogen, and nitrogen. However, this is dependant on the specific needs of the project. The omission of oxygen is a need to create increased resistance to corrosion
Stainless Steel Welding Preparations
In the first place, as in any other form of welding, the cleanliness of the stainless steel surface is paramount before starting to weld. Tools such as hammers and brushes are to be used on steel only as most of us do not understand how responsive stainless steel is to carbon steel. For example, using a stainless steel brush on carbon steel renders the brush useless for use on stainless steel again. The same holds for hammers and clamps. The reason is those trace elements of carbon embed generally in the stainless steel causing it to rust. Similarly, do not grind carbon steel close to SS. The dust will eventually settle to some extent on the SS causing rusting.
Down through the ages, in short, human beings have been hungry for improvements. From cars to homes to public utilities, usually, we desire everything to be aesthetic and efficient. This ever-ascending aspiration in all spheres of life is much welcome in the stainless steel industry. Stainless steel is non-corrosive and self-repairing by its inherent nature, in particular, thereby validating the growing demand. So for now, SS is here to stay till a more viable competitor throws the challenge.