Any power A machine that applies a sharp blow to the work area through the fall of a ram onto an anvil. The ram can be driven by gravity or power. See also Gravity Hammer and Power-Driven Hammer. where A cavity, or series of cavities (multiple), machined into a forging die to produce a desired configuration in the workpiece during forging. The metal blocks into which forging impressions are machined and from which forgings are produced. are not used for the reproduction of commercially exact forgings.