aws a5.18 er70s-6 pdf_what does the 7018 on a welding rod mean

Submerged-Arc Welding Wire is a type of welding wire that has been specifically designed for use in SAW applications. It is a metal wire, typically made from copper or stainless steel, that is submerged in an electric arc to create the weld. This method of welding provides many advantages over traditional arc welding techniques, including higher strength and improved penetration depth. Additionally, it produces cleaner welds with fewer porosity defects than other methods.