A Quick Guide on Welding Stainless Steel:
Protect Yourself:
Welding stainless steel or any metal absolutely requires wearing the right safety gear. A welding helmet and gloves are essential and other protective clothing is also advisable. Make sure you keep away from the fumes while you are welding, and read all relevant manufacturers, employers and safety procedures before you start.
Fit Up:
When you’re welding stainless steel, selecting the right joint design and fitting it up properly is crucial. Your welding position and access to the joint, the thickness of your stainless steel, and the required strength of the weld are all things you should consider. Depending on what you’re welding you may need to clamp your steel in place while you weld.
Weld Process:
There are several welding processes. ‘Stick welding’ is Shielded Metal Arc Welding. While inexpensive, it can be inefficient with slag coating that has to be removed. ‘Tig welding’ is Gas Tungsten Arc Welding. It conveniently requires little finishing after welding. Finally there are two types of ‘mig welding’; Flux Cored Arc Welding and Gas Metal Arc Welding. Flux Cored Arc Welding provides a stable arc and deoxidisation. Gas Metal Arc Welding can be done quickly and easily on all thicknesses of metals. After choosing your weld process, you need to choose the right inert shielding gas and wire. Remember when you are welding stainless steel with the same alloy, selecting a welding wire that is similar is essential. It will help to prevent cracking and ensure the join is similar to the base metal. You then need to set the parameters on the welder depending on the steel and process you’re using.
Welding and Finishing:
Make sure the surface of the steel is clean. That means free of paint, dirt, oil or anything else foreign. Wearing gloves while welding stainless steel will prevent oil from your hands getting onto the area you’re welding. Preheating is important for welding some stainless steel and less important for others. Preheat according to the type of stainless steel you’re using. Once all that preparation is done, you’re ready to weld. Postheat will prevent cracking by slowing down the cooling process. It also relieves stresses in the steel. This is particularly important if the steel you’ve welded is thick. Depending on your welding process, if there’s slag, remove it by chipping or grinding it off.