This paper presents on Casting as a manufacturing process which is used for making components of complex shapesof molten metal in mass production. Casting may experience many different defects such as porosity, incompletefilling, etc. Improving and maintaining the casting quality becomes an important task. Gating/riser system design iscritical to improve the casting quality. Different gating systems have different effects on the quality of castings. Twogating systems namely stepped and tapered runners were used to cast strip samples with different thicknesses byCO2/silicate process using sand grain sizes of AFS 151 and 171. Mould coating has effects on the properties of thinwall ductile iron. To access this, half of the moulds were coated while the rest were left uncoated. Molten metal withthe carbon equivalent of 4. 29% was prepared and poured at 1450º C. The results obtained by this experiment arestudied and thus, the effect of different gating systems is studied. Also, the mold filling affects the gating design.During light metal casting processes, the quality of a casting can be considerably affected by the pattern of moldfilling. In this study, the effect of gating design including gate geometry and size on the flow pattern was presented bypouring molten metal of aluminum alloy A413 into a sand mold. The experimental results indicate that the pattern ofmold filling is greatly influenced by the size and geometry of the gate and the ratio of the gating system.