Unformatted text preview: through the die, while those used for injection molding are designed to accumulate a bunch of melted plastic, called the “shot”, and then suddenly push (inject) it into the mold. After the mold has been filled, it is held closed long enough for the plastic to cool into the shape of the mold. The plug is then pulled out and the finished object is pushed out of the outer mold. As it is pushed out, a small piece of plastic from the sprue is broken off, leaving a tiny rough point at the center of the bottom of the container. This rough point can be used to identify a container made by the injection molding process. In a commercial facility, an injection molding machine may make only one large object at a time or as many as 150 smaller items, such as closures. Cycle time can range from a few seconds to as long as half a minute. 8. 20...
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- Spring '08
- Injection molding, Cycle Time, Plastics industry, injection molding machine