A straightening operation performed in either a 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. or a A machine tool with a stationary bed and a slide or ram that has reciprocating motion at right angles to the bed surface; the ram is guided in the frame of the machine. using flat or The machined recess in a die that gives the forging its shape. The metal blocks into which forging impressions are machined and from which forgings are produced. to remove undesired deformation and bring the The process of working metal to a desired shape by impact or pressure in hammers, forging machines (upsetters), presses, rolls, and related forming equipment. within straightness The permissible deviation from a specification for any design characteristic..