Dummy Blocks

Dummy Blocks

The most important factor in the effective operation of any dummy block is its’ efficient interaction with a round, straight, thermally, and therefore dimensionally, stable container


Allow gases to escape during the combined process of billet upset, and burp decompression, reducing blisters

Maintain a minimal uniform skin of aluminum on the liner inner diameter reducing profile inclusions


The function of the dummy block is the extension of the ram or stem, which pushes the softened alloy through the die. Key functions include:

To repeatedly transmit the force of the ram, at high temperature, to the alloy

To expand to pre-determined size under load and maintain a secure seal with the container wall

To cause no gas entrapment that can result in blistering, or damage the face of the container and/or dummy block


Reduce scrap, due to back end blisters and surface defects

Increase container liner life