New Stamping Technology Reduces Die-Roll

This new stamping technology reduces and possibly eliminates the die-roll around holes that is caused from the piercing punch deforming the material.

Die-roll on stampings is a natural phenomenon of the metal stamping process that manufacturing has wrestled with for ages. It is the slightly curved contour on the edge of one side of a blanked part (opposite to the burr side) and is created by the amount of pull-down on the part material before the actual cutting of the material starts.  For a variety of reasons, designers, engineers, and end-users of stamped parts have often asked to eliminate or reduce the die-roll.

Metal stamper Ebway Corporation (Fort Lauderdale, FL) developed technology to reduce the amount of die-roll on pierced holes.  This quest started when a certain Request for Quote (RFQ) specified minimum die-roll on the holes. Upon further discussions with the customer, it was learned that the 0.409 in thick low carbon steel part was used within an automotive assembly and hex-headed bolts fastened the part to a mating surface.

The customer was concerned with the possibility of an irregular surface due to the die-roll on the holes which may cause the heads of the bolts (as they were tightened) to put uneven pressure (not seat properly) on the part and resulting in cocking the part so it would not be parallel to the mating surface.

The manufacturer designed and made a special stamping die that reduced the die-roll to the customer’s satisfaction. The customer was then able to use the parts as stamped, putting an end to any secondary machining or grinding operations.  The technology is available to be used on materials from 0.060 in to 0.500 in thick.

www.ebway.com