Plastic moulding methods
-Introduction : -Large number of method used for processing of plastic. This method is depend upon type of plastic, softening temperature, geometry, size of finished product. - Following are plastic moulding processes: 1. Compression moulding. 2. Injection moulding. 3. Blow moulding. 4. Vacuum forming. 5. Extrusion. 6. Calendaring. -Above plastic moulding processes are discuss in detail one by one. 1. Compression moulding: Compression molding is similar process of closed die forging process. It is mostly used for thermosetting plastic. In this process plastic is put on heated mould and compress under suitable pressure and temperature. -Process consist following step: 1. Use moulding material loose powder and granules into heated die cavity. Temperature varies between 150°C to 180°C. 2. Close the split mould between press plate. Pressure around plate is 30 N/mm2 to 60 N/mm2. 3. Open the split mould. Eject product from the mould manually or automatically. 4.blow out the ...