These often form the basis for choosing casting over other shaping processes such as machining, forging, welding, stamping, rolling, extruding, etc. As a result, many other operations, such as machining, forging, and welding, can be minimized or eliminated. Because of their physical properties, some metals can only be cast to shape since they cannot be hot-worked into bars, rods, plates, or other shapes from ingot form as a preliminary to other processing. Construction may be simplified. Objects may be cast in a single piece which would otherwise require assembly of several pieces if made by other methods.
Metal casting is a process highly adaptable to the requirements of mass production.
Large numbers of a given casting may be produced very rapidly. For example, in the automotive industry hundreds of thousands of cast engine blocks and transmission cases are produced each year. Extremely large, heavy metal objects may be cast when they would be difficult or economically impossible to produce otherwise. Large pump housing, valves, and hydroelectric plant parts weighing up to 200 tons illustrate this advantage of the casting process. Some engineering properties are obtained more favorably in cast metals.