Welding joints

Welding is joining of two pieces of similar metals by heating and adding of a filler material. The welded material may be shielded or unshielded. The shielding material is usually inert gas and it protects the welding process and materials being welded together. Welding processes are coated electrode welding, lo-hydrogen coated electrode welding, Tungsten inert gas welding, or the latest Plasma welding.

More about welding at http://www.1spotwelding.com/index_1.html