Pre-pierce

(1) In ring rolling, a vertically mounted piercing (punching) tool used for preparation of ring blanks on the ring blankRaw material or forging stock (also called a "slug" or "multiple") from which a forging is made. pressA 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.. (2) A tapered tool of various diameters and lengths.