Some include blow moulding injection blow moulding

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Unformatted text preview: usion Blow Moulding Stretch Blow Moulding Polymer Polymer processing There are a variety of different processing methods used to convert resins into finished products. Some include: Thermo forming Vacuum Forming Pressure forming Thermoforming Thermoforming Thermoforming is a method of manufacturing custom plastic enclosures by preheating a flat sheet of plastic and bringing it into contact with a mold whose shape it takes. This can be done by vacuum, pressure and or direct mechanical force. Pressure Pressure Forming Pressure forming involved forcing a hot plastic sheet against a mold by introducing compresses air to the sheet's outer side. Vacuum Vacuum Forming It involves the automatic draping of a heatsoftened plastic sheet over a female or male mold. Injection Injection Moulding Plunger type The main problem with a straightforward plunger arrangement was that no melt mixing or homogenisation could be readily imparted to the thermoplastic material Injection Moulding Reciprocating Reciprocating screw injection moulding unit Injection Injection Moulding • Injection Moulding Process • 1. Screw Plasticating • 2. Moulding Injection Injection Moulding • Material is introduced into the injection moulding machine via a Hopper. The injection moulding machine consists of a heated barrel equipped with a reciprocating screw (driven by a hydraulic or electric motor), which feeds the molten polymer into a temperature controlled split mould via a channel system of gates and runners. • The screw melts (plasticizes) the polymer, and also acts as a ram during the injection phase. The screw action also provides additional heating by virtue of the shearing action on the polymer. • The polymer is injected into a mould tool that defines the shape of the molded part. PLASTICATING PLASTICATING Plasticating refers to conversion of plastic granuals to flow-able melt. It happens inside the screw barrel assembly of the injection unit in the Injection Moulding Machine. PLASTICATING PLASTICATING- How? The plastic granules move insi...
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This document was uploaded on 03/14/2014.

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