In Option B, the heavy section hub is positioned  high in the mold and the riser (which also acts as a pouring inlet) is positioned directly over the hub.

• The tapered riser  (6" tall and 3" diameter) has an exothermic sleeve to ensure that it remains molten.

This design ensures that the heavy hub section, which is the last section to solidify, will always be fed with molten metal by the attached riser and will solidify without shrinkage porosity.