In tilt pour casting, the metal is poured into a holding cup while the mold is in its horizontal position. Then, with a preset cycle time, the casting machine raises to a vertical position, allowing the metal to enter the die cavity at a slow, continuous pour rate. The tilt-pour method is a good choice for general casting purposes because of its feed/gate flexibility which allows for a wide variety of casting shapes.
Temperature profile during a tilt pour filling cycle
In this example, a simulation of a tilt pour process was performed on an aluminum coupler cable run to cable tap to ensure part integrity and surface quality. The time it takes to complete the tilting rotation is important. The rotation rate can be easily modified in FLOW-3D Cast allowing the user to optimize this speed: too fast and air will be entrained into the flow, too slow and there will be more surface defects. The temperature profile is visualized by setting the maximum and minimum graph values as the liquidus and solidus temperatures, respectively. Here, the part is halfway filled and the metal temperature is not near its solidus temperature so there will be no early solidification.
Tilt pour casting animations
Surface oxide and entrained air defects
Lightweight aluminum parts used in water sports rafting equipment require high-quality finish and are cast to be ideally devoid of surface and entrained defects. This simulation of the tilt pour casting process shows potential regions of trapped surface oxides and entrained air through the filling process. Knowing the movement of these defects helps metal casters design better gating, runners and risers to eliminate defects within the casting. FLOW-3D Cast can be used to simulate complex tilting sequences and angular acceleration/decelerations of the die through its proprietary 6 DOF moving capability.
Velocity contours and thermal gradients
A precise control of alloy velocity through tilting process minimizes casting defects such as turbulent gas porosity. This animation shows velocity contours within the sprue and gating design through the automated tilting sequence. Analyzing the temperature gradients indicate early solidification and hot metal front to better design the die for shrinkage defects and solidifying volume compensation.