Due to the great difference between lost foam casting and traditional sand casting, the process design of lost foam casting should be based on the basic theory of traditional sand casting process, and its own process characteristics should be considered in order to design the process scheme reasonably. At the same time, the production cost and economic benefit of the enterprise should also be considered on the premise of ensuring the output and quality.
The gating system is the channel through which molten metal is injected into the mold cavity. It is usually composed of gate cup, sprue, runner and runner. Because EPC belongs to real mold casting, the filling characteristics of metal liquid are quite different from that of cavity casting. The filling process of molten metal is the process of metal liquid replacement foam pattern.
When molten molten metal is poured into the runner, the foam pattern softens, melted, vaporized and burned under high temperature. A physical and chemical reaction occurs between a liquid column and a liquid column.
Some researchers have observed the filling behavior of molten aluminum alloy by various methods, such as cold quenching, high-speed photography and electrode contact method. The research shows that when the molten metal enters the mold filling state, the gate is centered and radiated arc advancing in sequence. The foam pattern is replaced by layer by layer, and finally filled to the part far away from the gate. The filling state of the molten metal is directly influenced by the characteristics of the mould, coating performance, negative pressure and pouring system.