Applicable methods for reducing melt velocity in gating systems: Simulation and comparative evaluation of usable techniques

Foundry is one of the most commonly used and least expensive methods for producing metallic parts. Many defects can occur during the casting of parts; however, most of these defects can be avoided by designing an effective running/gating system. In this regard, the velocity of the melt entering the mold is a critical parameter in forming a flawless and defect-free component. The gating system is responsible for controlling this velocity. If the entry rate is too high, causing the metal to fountain or splash inside the mold cavity, the quality of the casting is compromised. In this paper, methods developed to reduce melt velocity were investigated using simulation to avoid defects such as oxide cracks. These methods include an extended runner, filtering, a fan ingate, and a diffuser to reduce velocity by increasing the cross-sectional area. By applying these methods simultaneously in a single design, the velocity of the melt entering the mold was controlled and maintained at 0.5 m/s. The importance of the critical value of 0.5 m/s was demonstrated through simulation. The findings of this paper could help foundry engineers design gating systems that produce high-quality, defect-free steel castings, such as those used in marine and automotive applications.