Plastic injection molding

|Plastic Injection Moulding – An Introduction |
|Topics Covered |
|Introduction|
|Historical Background |
|The Injection Moulding Cycle |
|Mould Close and Clamping|
|Injection |
|Holding Pressure and Cooling |
|Materials Dosing and Metering|
|Mould Open and Part Ejection |
|Mould Design |
|Injection Moulding Machine Selection Criteria|
|The Mould |
|The Clamping Unit |
|The Injection Unit|
|Moulding Quality |
|Weld lines |
|Shrinkage|
|Splash Marks |
|Distortion and Moulded in Stress |
|Introduction|
|One of the most common methods of converting plastics from the raw material form to an article of use is the process of injection |
|moulding. This process is most typically used for thermoplastic materials which may be successively melted, reshaped and cooled. |
|Injection mouldedcomponents are a feature of almost every functional manufactured article in the modern world, from automotive |
|products through to food packaging. This versatile process allows us to produce high quality, simple or complex components on a fully |
|automated basis at high speed with materials that have changed the face of manufacturing technology over the last 50 years or so. |
|HistoricalBackground |
|To understand the engineering and operation of modern day injection moulding machines, it is useful to first look at the not too |
|distant origins of the process. The first injection moulding machines were based around pressure die casting technology used for...