GLOSSARY OF PRESS TOOL TERMS

GLOSSARY OF PRESS TOOL TERMS

ANNEALING:
A process involving the heating and cooling of a metal, commonly used to induce softening.
The term refers to treatments intended to alter mechanical or physical properties or to produce a definite microstructure.
BEAD:
A narrow ridge in a sheet-metal work piece or part, commonly formed for reinforcement draw:
(a) A bead used for controlling metal flow.
(b) Rib like projections on draw ring or hold-down surfaces for controlling metal flow.
BED, PRESS:

The stationary and usually horizontal part of a press that serves as a table to which a bolster plate or lower die assembly is mounted.

BEND ANGLE:
The angle through which a bending operation is performed.

BENDING:
The straining of material usually flat sheet or strip metal, by moving it around a straight axis which lies in the neutral plane.

BEND RADIUS:
(a) The inside radius at the bend in the work
(b) The corresponding radius on the punch or on the die.

BLANK:
A precut metal shape, ready for a subsequent press operation.

BLANK DEVELOPMENT:
(a) The technique of determining the size and shape of a blank.
(b) The resultant flat pattern.

BLANK HOLDER:
The part of a drawing or forming dies which holds the work piece against the draw ring to control metal flow.
BLANKING.
The operation of cutting or shearing a piece out of stock to a predetermined contour.


BOLSTER PLATE:
A plate secured to the press bed for locating and supporting the die assembly.

BUCKLING:
A bulge, bend, kink, or other wavy condition of the work piece caused by compressive stresses.


BULGING:
The process of expanding the walls of a cup, shell or tube with an internally expanding
segmental punch or a punch composed of air, liquids, or semi liquids, such as waxes or Rubber and other elastomers.
BURNISHING:
The process of smoothening or plastically smear¬ing a metal surface to improve its finish.
BURR SIDE:
The side of a punched blank that presents a rough edge around its periphery or around a hole or opening in it.

CAM ACTION:
A motion at an angle to the direction of an applied force, achieved by a wedge or cam.

DIE HEIGHT (SHUT HEIGHT):
The distance from the finished top face of the upper shoe to the finished bottom face of the lower shoe, immediately after the die operation and with the work in the die.

DIE HOLDER:
A plate or block upon which the die block is mounted.

DIE RADIUS:
The radius at the edge of a female die over which metal is formed or drawn into the die.

DRAWABILITY:
(a) A measure of the feasible deformation of a blank during a drawing process;
(b) Percentage of reduction in diameter of a blank when it is drawn to a shell of maximum practical depth.

DRAWING:
A process in which a punch causes flat metal to flow into a die cavity to assume the shape of a seamless hollow vessel.

EMBOSSING:
A process that produces relatively shallow indentations or raised designs with theoretically no change in metal thickness.
EXTRUSION:
The plastic flow of a metal through a die orifice.

IRONING:
An operation in which the thickness of the shell wall is reduced and its surface smoothened.

KNOCKOUT:.
A mechanism for ejecting blanks or other work from a die. Commonly located on the side, but may be located under the bolster.

NOTCHING:
The cutting out of various shapes from the edge of a strip, blank, or part.

PARTING:
An operation usually performed to produce two or more parts from one common stamping.

PIERCING:
The process of die-cutting holes in sheet or plate material. Pilot pin or projection provided for locating work in. subsequent operations from a previously punched or drilled hole.
PRESS:
A machine having a stationary bed or anvil, and a slide (ram or hammer) which has a controlled reciprocating motion toward and away from the bed surface and at right angles to it. The slide being guided in the frame of the machine to give a definite path of motion.

PUNCH:
(a) The male tool part, usually the upper member and mounted on the slide;
(b) To die-cut a hole in sheet or plate material;
(c) A general term for the press operation of producing holes of various sizes in sheets, plates, or rolled shapes.

PUNCH HOLDER:
The plate or part of the die which holds the punch.

SCRAP CUTTER:
A shear or cutter operated by the press 6r built into a die for cutting scrap into sizes for convenient removal from the die or disposal.

SHAVING:
A secondary shearing or cutting operation in which the surface of a previously cut edge is finished or smoothened.

SHEAR:
(a) A tool for cutting metal and other material by the closing motion of two sharp, closely adjoining edges;
(b) To cut by shearing dies or blades;
(c) An inclination between two cuttings.

SLITTING:
Cutting or shearing along single lines; used either to cut strips from a sheet or to cut along lines of a given length or contour in a sheet or part.

SLUG:
A small piece of material, usually scrap, produced in piercing or punching holes in sheet material.



SPOTTING:
The fitting of one part of a die to another, by applying an oil color to the surface of the finished part and bringing it against the surface of the intended mating part, the high spots being marked by the transferred color.

SPRING-BACK:
The extent to which metal tends to return to its original shape or position after undergoing a forming operation.

STAMP:
(a) The general term to denote all press working;
(b) To impress lettering or designs by pressure into the surface of a material.

STRIPPER:
A device for removing the work piece or part from the punch.

STRIPPER PLATE:
A plate (solid or movable) used to strip the work piece or part from the punch; it may also guide the stock.

STRIPPING:
The operation of removing the work piece or part from the punch.

TRIMMING:
Trimming is the term applied to the operation of cutting scrap off a partially or fully shaped part to an established trim line.