Simulation study on integrated bottom car body formation by high pressure die casting with a dual injection system

• Dual injection system significantly reduces cold shuts and solidification time compared to single injection in large die-casting. • Scaled model at 1:3 ratio successfully replicated real casting conditions, validating the dual injection approach. • The study provides both theoretical insights and practical guidance for producing integrated bottom car bodies via die casting. • The dual injection system addresses challenges of extended filling time and metal flow distance in large integrated castings.