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Plastic moulding method 2 ( blow moulding and extrusion)

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-Plastic moulding methods: - Blow moulding. -Extrusion. -Blow moulding: - process consist following step . 1. In a blow molding hot soft plastic is squeezed into mould. 2. compressed hot air is used to blow a big  bubble  inside a Mould. 3. the plastic swells  out like a balloon until it fills up the whole mould. In this way many plastic bottles, toys are manufactured. 4. blow molding is like injection moulding except that hot liquid plastic pours out of a barrel vertically in a thermoplastic closed end tube. 5. the mould is closed and force how to outward direction to confirm inside shape of mould. 6. After sometime cooling remove the mould. Hollow part is formed. Fig.Stages in in blow molding. -Advantage: 1. Low tool and die cost. 2. complex Hollow shapes possible. 3.high production rate. - Disadvantage: 1. Hollow shape tolerances hard to control. - Application: Example of blow moulding bottle, tubes, containers a, heaters ducts etc. - Extrusion process: 1. it is continuous process.
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Plastic moulding methods

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-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 tool for remov
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Plastic Moulding

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Introduction: -A plastic can be defined as any non- metallic material can be moulded into any  desired shape. -The word plastic derived from Greek   plastikos, means "fit for molding". -Plastic are systematically produce non-   metallic compound. They can be moulded into various form and harden for commercial use.plastic molding product can be seen everywhere. -Following are example of plastic moulding jars, protective cap, plastic tube, grips, toys, kitchen utensils, bottle and lot of more.                     Product of plastic - The basic idea in plastic moulding is inserting molten liquid plastic into a ready  shape mould, for example the mould of a bottle. It will be  allowed  to cool, then it will be remove. Properties of plastic: - It is light in weight. -it is high strength to weight ratio. -it is relatively inexpensive  - most plastic are chemically stable. -it is easily transparent and colored. -They have good insulation and thermal     property. - good
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