Casting-appropriate engineering involves optimized design and/or layout of the casting system (Gating system) and the mold, including sufficiently dimensioned wall thickness ratios.
Complete and thorough filling with regard to the aspect of direct solidification is ensured when every cross section at a casting issues into an equally sized or enlarging connection with a riser (see Heuvers circle method).
In this way, the solidifiying metal can flow into and fill up the solidifying and shrinking sections and prevent a volume deficiency at the inside of the cast part. If a part is insufficiently designed to suit casting requirements, a large number of risers (i.e. increased demand in molten metal = diminished casting yield), cooling ingots, special mold materials, etc. are required. Overall, the entire production process becomes more economically inefficient. Thick-walled sections always involve problems with redard to feeding, therefore, junctions must be eliminated if possible. General engineering principles are listed below and illustrated by the Figures 1 and 2