Pre-drying (injection moulding)
From EverybodyWiki Bios & Wiki
A Pre drying is a process needed during Injection Moulding process to remove moisture from polymer material. Plastics materials are hygroscopic and pre-drying is important before Injection moulding. Plastics materials are packed into bags which contain 25 kg and each material grade has a recommended maximum moisture content for defect free processing.
[1]
Allowable moisture content for different polymers[edit]
| Polymer Family | Acceptable Moisture content (%) |
|---|---|
| Acrylonitrile butadiene styrene | 0.1 |
| Polycarbonate | 0.02 |
| Polyamide | > 0.2 |
| Polybutylene terephthalate | 0.03 |
| Polyethylene terephthalate | 0.02 |
| Styrene-acrylonitrile resin | 0.1 |
| Thermoplastic elastomers | 0.1 |
| Polycarbonate+ Acrylonitrile butadiene styrene | 0.04 |
| Description | Problems while moulding | Defects in moulded parts |
|---|---|---|
| Defects | Drooling | Silver streaks |
| Defects | Bubble in purge | Surface blemish |
 | This industry-related article is a stub. You can help EverybodyWiki by expanding it. |
This article "Pre-drying (injection moulding)" is from Wikipedia. The list of its authors can be seen in its historical and/or the page Edithistory:Pre-drying (injection moulding). Articles copied from Draft Namespace on Wikipedia could be seen on the Draft Namespace of Wikipedia and not main one.
