Plastic Extrusion
Plastic extrusion is the process where plastic materials are converted from solid to liquid and then it is reconstituted into finished products. In other words, plastic is melted down and then reshaped into useful items. There are some advantages to plastic extrusion, but there are also a few disadvantages that must be considered.
Advantages of Plastic Extrusion
3 of the major advantages of plastic extrusion are as follows.
- Low Cost: Compared to other molding processes, plastic extrusion molding has a low cost and is more efficient. The extrusion molding process uses thermoplastics and they undergo repeatedly melting and hardening, this allows the waste to be reused rather than be discarded. Raw material and disposal costs are lowered. Plastic extrusion machines operate continually and this reduces the chances of inventory shortage. It also allows for 24-hour manufacturing.
- Better Flexibility: Extrusion molding will provide considerable flexibility in the products being manufactured with a consistent cross section. As long as the cross section stays the same, the extrusion molding can produce complex shapes. Minor alteration to the plastic extrusion process the manufacturers can use it for plastic sheets or produce products that mix plastic attributes.
- After Extrusion Alterations: Plastics remain hot when they are removed from the extruder and this allows for post-extrusion manipulations. Many manufacturers will take advantages of this and use a variety of roller, shoes and dies to change the shape of the plastic as needed.
Disadvantages of Plastic Extrusion
Plastic extrusion has also some disadvantages.
- Expansion: Once the hot plastic is removed from the extruder it will many times expand. This is called die swell. It is problematic to try and predict the exact degree of expansion. Because it is hard to predict the exact expansion, manufacturers often accept significant levels of deviation from the dimensions of the product.
- Product Limitations: Extrusion plastic molding does place limits of the types of products that can be manufactured. There are alternatives that require an investment in a different type of extrusion equipment.