Die casting is a high precision, rapid parts-production process involving the high pressure injection of molten metal into a die having a cavity of the desired part shape.
Part of the Fundamental Manufacturing Processes Video Series, this program explores the common die cast metals and their various properties, as well as die casting machines and die cast tooling. The die casting machines segment covers in detail both the hot-chamber and the cold-chamber machine types. Also discussed is the importance of die casting lubrication and application in die casting, clamping systems, the use of accumulators and pressure intensifiers, and machine controls and automation. The die cast tooling segment examines the various die production materials and techniques. In addition, terms such as cover die, ejector die, fixed cores, movable cores core pulls, venting, die cooling, and draft angles are clearly defined. For more information and to purchase, visit http://www.sme.org/fmp service@sme.org | 800.733.4763 | http://www.sme.org/store
"The die halves are attached to platens on the die casting machine. These platens are large, thick blocks of steel which will not deflect during injection. They include the stationary platen and the movable platen. The stationary platen holds the die half that is called the cover half. This platen has a hole directly in line with the metal injection cylinder.
The movable platen holds the other die half called the ejector half. This movable platen slides back and forth on weighs. When the metal has solidified and the die halves separate, mechanically or hydraulically actuated ejector pins release the casting from the ejector half of the die.
Before closing, the die halves are lubricated by external sprays to assist in cooling, casting release and to minimize die wear. Lubricants, usually water soluble, can be manually applied but are often sprayed automatically using central die spray systems.
The application of die spray is usually followed by an air blast to blow off residual water and to remove any loose metal left from the previous shot.
After release from the die, the casting can be removed manually with tongs or dropped on a conveyor or down a shoot for transfer from the machine or removed using automatic extractors. These extractors are commonly used and often provide automatic die spray lubrication."
