A heavy gray iron counterweight has weight of 50 t, thickness of 600 mm. Four hot Connor feeders wereused so that the metal was entering the casting cavity through the feeders. In order to prevent surface sinks andinner shrinkage defects, a lot of internal denseners had been set in the mold cavity. To prepare denseners and fixthem in the mold cavity caused large amount of work, however the quality of castings was not very good. Therefore,considering that heavy castings with high carbon equivalent would have...