Injection Molding Tooling and Molds Machining and Cost

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Injection Molding Process Types

Injection Molding Cycle: The sequence of events during the injection mold of a plastic part is called the injection molding cycle. The cycle begins when the mold closes, followed by the injection of the polymer into the mold cavity. Once the cavity is filled, a holding pressure is maintained to compensate for material shrinkage. In the next step, the screw turns, feeding the next shot to the front screw.This causes the screw to retract as the next shot is prepared. Once the part is sufficiently cool, the mold opens and the part is ejected.

Different types of injection molding processes: Although most injection molding processes are covered by the conventional process description above, there are several important molding variations including:

• Co-injection (sandwich) molding
• Fusible (lost, soluble) core injection molding
• Gas-assisted injection molding
• In-mold decoration and in mold lamination
• Injection-compression molding
• Insert and outsert molding
• Lamellar (microlayer) injection molding
• Low-pressure injection molding
• Metal injection molding
• Microinjection molding
• Microcellular molding
• Multicomponent injection molding (overmolding)
• Multiple live-feed injection molding
• Powder injection molding
• Push-Pull injection molding
• Reaction injection molding
• Resin transfer molding
• Rheomolding
• Structural foam injection molding
• Structural reaction injection molding
• Thin-wall molding
• Vibration gas injection molding
• Water assisted injection molding
• Rubber injection
• Injection molding of liquid silicone rubber

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