Blank

Where it comes up

• Metal stampingShort- to medium-run stampings: brackets, clips, shields, and plates cut and formed from sheet or coil in a press.
• Deep drawn stampingOne-piece cups, cans, shells, and housings drawn from flat blanks, with depth that can exceed the diameter.
• Sheet metal fabricationLaser-cut, punched, bent, and welded sheet metal enclosures, brackets, and chassis with no hard tooling.

Related terms

Progressive die

A progressive die is a stamping die with a series of stations that pierce, form, and cut a part in sequence as a metal strip feeds through the press. One finished part drops with each stroke. It is the lowest piece-price option for high-volume small and medium stampings.

Transfer die

A transfer die is a stamping setup where separate stations each perform one operation and mechanical fingers move the part between them after it is cut from the strip. It handles larger or deeper parts, such as deep drawn shells, that cannot stay attached to a carrier strip.

Draw ratio

Draw ratio is the ratio of blank diameter to punch diameter in a deep drawing operation. It sets how far one draw can reduce a blank before the metal tears. A first draw in steel is typically limited to about 1.8–2.2, so deeper parts need redraw stations.

Burr

A burr is the raised, sharp edge of material left on a part after shearing, punching, or machining. Stamping drawings often allow burr height up to 10% of material thickness and state which side the burr may fall on. Removing burrs adds a secondary operation and cost.