Castool Tooling Systems – Die Cast Toolings (Die Vacuum Control Systems)
Description
In cold chamber die casting, the alloy is forced into the mold cavity with such force and velocity that small quantities of air and gases are often trapped in the casting. If the casting is structural, heat treated, or porosity sensitive, air or gas inclusions usually result in rejection. This impacts directly on the die caster’s bottom line. In today’s competitive market, this preventable problem is no longer acceptable.
The solution is the Castool Vacuum System, which ensures a consistent high-quality casting, and a guaranteed reduction in scrap due to porosity.
Before the injection shot occurs, a vacuum is drawn in both the shot sleeve and the mold cavity. The vacuum is maintained until the injection cycle is completed. When the cast is filled up to the chill vent cavity, the chill vent solidifies the cast and closes immediately. Almost all of the air is positively evacuated from the mold. A good vacuum in the mold cavity enables the alloy to flow into blind recesses in complex shapes. It also allows the front of the molten metal to merge freely.
A properly designed chill vent with improved thermal conductivity can increase quality and reduce scrap due to porosity. No additional water cooling is required. Also up to 20-40, 000 shots can be expected before maintenance is required. A problem that is shared by most die casters – the unplanned downtime that occurs when casting must be discontinued before the scheduled production run – has been eliminated.
