A riser sleeve made of a highly exothermic material, the volume of which nearly corresponds to the material shrinkage during solidification, resulting in minimum circulation material.
In 1977, the mini riser was developed by the Rexroth foundry in Lohr/Main in cooperation with former company Lüngen (today ASK Chemicals Feeding Systems) and represented a quantum leap in riser technology. It enabled a considerable reduction in feeding volume (Fig. 1). ASK Chemicals Feeding Systems is the sole beneficiary of the patent DE-B-2010337 describing a method for reducing the riser volume of a riser made of an exothermic heating compound for castings.
The benefits of mini risers are obvious: