Injection Molding

What is it?

1. A molten plastic (liquid) is injected into a steel mold.
2. Plastic cools down (using cold runners)
3. Steel tool opens
4. Parts fall out

What is needed?

1. A mold (usually made from steel)
2. Plastic granules

What is it typically used for?

1. Housing (the part of the product you normally see)
2. Transmissions
3. Joints

What are the advantages?

1. Low part cost
2. High volume production
3. Good surface finish
4. Simplies assembly

What are the disadvanteges?

1. High tooling cost
2. Dificult to make changes
3. Requires uniform wall thickness
4. Long lead times