Table mill

In ring rolling, a type of ring forging equipment employing multiple mandrels with a common main roll. Usually used in high volume production of small-diameter rolled rings.

Target machining

Incorporating a “target” (benchmark or gage point) on a forging to facilitate machining; coined locating surfaces and drilled centers are commonly used.

Template (Templet)

A gage or pattern made in a die department, usually from sheet steel; used to check dimensions on forgings and as an aid in sinking die impressions in order to correct dimensions.

Thermal cracks

Ruptures in metal set up by stresses due to thermal differentials.

Thermomechanical working

A general term covering a variety of processes combining controlled thermal and deformation treatments to obtain synergistic effects, such as improvement in strength without loss of toughness.


The permissible deviation from a specification for any design characteristic.


Metal holder used to handle hot or cold forgings.

Tool steel

A superior grade of steel made primarily for use in tools and dies.

Tooling marks

Indications imparted to the surface of the forged part from dies containing surface imperfections or dies on which some repair work has been done. These marks are usually slight rises or depressions in the metal.


Removal of a core of metal by a hollow tool. May be performed by a hollow punch at forging temperatures or by a hollow cutting tool by machining at ambient temperatures.


The removal of the excess metal or flash produced during the forging process. The operation takes place in tools produced to the peripheral shape of the component, the component being pushed through the female impression by the identically-shaped male punch. The operation may be carried out hot or at room temperature.

Trim and punch

(1) A shearing operation to remove both an inner and an outer section of metal from a blocked or finished forging. (2) A combination of two operations whereby flash and punchout are removed simultaneously. The operation is generally performed on a trim press using a combination trim and punch die.

Trimmer die

The upper portion of the trimmer that comes in contact with the forging and pushes it through the trimmer blades; the lower end of the trimmer punch is generally shaped to fit the surface of the forging against which it pushes. Also termed Trimmer punch.


Preparatory run to check or test equipment, lubricant, stock, tools, or methods prior to a production run. Production tryout is run with tools previously approved; new die tryout is run with new tools not previously approved.


(1) The process for removing scale from forgings in a rotating container by means of impact with each other and abrasive particles and small bits of metal. (2) A process for removing scale and roughness from forgings by impact with each other, together with abrasive material in a rotating container.


Removing metal from the outside of a part by means of a tool in a lathe or similar machine tool.

Ultrasonic testing

A method of nondestructive testing of solid metal for internal flaws utilizing high-frequency sound waves.


The Unified Numbering System. A system that provides a means of correlating many nationally used numbering systems currently administered by societies, trade associations, and individual users and producers of metals and alloys, thereby avoiding confusion caused by use of more than one identification number for the same material. It also avoids having the same number assigned to two or more entirely different materials.

Upset forging

(1) A forging made by upsetting an appropriate length of bar, billet or bloom. (2) Working metal to increase the cross-sectional area of a portion or all of the stock. (3) A forging formed by heading or gathering the material by pressure upon hot or cold metal between dies operated in a horizontal plane.


A small hole in a punch or die for admitting air to avoid suction holding or for relieving pockets of trapped air that would prevent die closure or action.

Vent mark

A small protrusion resulting from the entrance of metal into die vent holes.


Term generally applied to distortion that results during quenching from heat-treating temperatures; hand straightening, press straightening, or cold restriking is employed, depending on the configuration of the part and the amount of warpage involved. The condition is governed by applicable straightness tolerances; beyond tolerances, warpage is defect and cause for rejection. The term is not to be confused with “bend” or “twist.”


A relatively flat, thin portion of a forging, generally parallel to the forging plane—that connects ribs and bosses. See also Rib.

Wrought steel

A descriptive term for any particle of steel that has been produced by hot mechanical working.