Choosing the best method for welding stainless steel completely depends on what qualities you are looking for and the material you are using. Obviously, there is more than one stainless steel welding method, and it is important that you choose the right one for the job so that your finished product is of the best quality possible.
Resistance Spot Welding – best for joining sheets together
Resistance spot welding is the best method for welding stainless steel that involves two or more metal sheets. The process works by applying pressure and heat from the electric current to the weld area. An electric current is delivered to the sheets through electrodes. The force that is applied is converted to heat which allows for the welding process to happen.
Gas Tungsten Arc Welding – best for thin sheets
Gas Tungsten Arc Welding, both automatic and manual, is normally used for joining conventional and Precipitation Hardening (PH) stainless steel – particularly thicknesses of up to about 0.25 inches. However, all weldable stainless steel alloys can be welded readily using the Gas Tungsten Arc Welding method.
This stainless steel welding method utilises a shielding gas that is usually argon based, but helium or mixtures between the two is also used for heavier sections. Using argan gas means that the flow and voltage rates are lower, lessening the likelihood of burning through thin sheets of stainless steel.
Gas Metal Arc Welding – best for thick sheets
Gas Metal Arc Welding is the best method for welding stainless steel if the steel involves long joints in thick material and/or there are many components to be welded. Common techniques used with the Gas Metal Arc process are spray arc and short-circuiting.
A spray transfer is named as such because the technique is similar to that of a spray coming out of a restricted garden hose. Instead of water, however, the spray is tiny molten droplets. A spray transfer is typically smaller than the diameter of the wire and uses a higher voltage, better suited to thick sheets of stainless steel.
Whereas short-circuit transfers consist of a continuous consumable wire electrode, once the arc is established, the arc is always ‘on’. The advantage of the short-circuit transfer is its low energy, as such, it is usually used on thin material that is ¼ inch or less.
Deciding on the best method for welding stainless steel can sometimes be complicated – especially if you are new to the trade. The team at Rapid Fab are experts in the welding and fabrication industry and are happy to assist with welding methods and best practices. Contact the team at 07 5529 2622 for any questions you might have regarding stainless steel and welding methods.