Investigation of Ductile Casting Iron Risers in the Simulation Method

Abstract

On one hand, risers are one of the most important means to avoid shrinkage defects in castings; on the other hand, they increase greatly metal consumption for castings. Due to weight of a casting, weight of a riser can make about 50 – 100 % of weight of the casting. However, volume shrinkage of metal and the size of a riser can be influenced, as well, by technological casting factors. Influence of technological casting factors to shrinkage of castings was investigated in the method of digital simulation, using an original computer program. Research results show that the mould pouring time, metal temperature, thermo-physical characteristics of a casting mould, and relevant wall thickness of a casting have a significant effect on the volume shrinkage of ductile iron castings and on the dimensions of risers. These results will help to predict volume shrinkage of ductile iron castings more precisely and to decrease metal consumption for a casting.