From the Latin, patella, which is a large round metal pot or vessel, boilermaking (pailería, in Spanish) or boilerworks is a technique used for cutting and joining pieces of metal or sheet metal in order to produce metallic deposits to store and/or transport materials, be they solids, liquids or gasses. They tend to be large pieces which are shaped and welded with other smaller ones. The process uses techniques such as mapping, straightening, cutting and welding for plates, tubes and profiles.