In this document Plastic and Polymer Composite - Fabrication Processes, there are many contents: injection molding (or compression or transfer), extrusion, thermo-forming, blow molding (injection blow molding with preforms or extrusion blow molding with parison), rotational molding (combination of 3 and 4). | Chapter 9 – Plastic and Polymer Composite Fabrication Processes Injection Molding (or compression or transfer) Extrusion Thermo-Forming Blow Molding (injection blow molding with preforms or extrusion blow molding with parison) Rotational Molding (combination of 3 and 4) Molding Processes for PE: Molding Processes for Nylon (30% GF): You Tube Videos: Blow Molding: Extrusion: Injection: Thermoforming: Injection Molding – most common (60-70%) Process Plastic pellets are heated in the injection unit and forced through a runner system/gate(s) into a cavity in a mold. Batch Process Injection Molding Equipment Clamping Unit (Ejection System) Injection (Plasticating) Unit Frame Injection Molding Main functions of Plasticating unit Convey solid material/melt Mix to produce homogeneous melt Melt material Range of 300º F (PVC) to 740º F (Polysulphone) Develop pressure for injection Injection Molding Materials Both amorphous and semi-crystalline are done easily Narrow molecular weight distribution With modifications to the equipment – thermoset materials and liquid Silicone can be used Injection Molding Parts Three dimensional Can be very complex Multiple cavitation is common (128 cavities) Injection Molding Tooling - Molds Generally steel, but some Aluminum tooling is used High pressure process – molds are ‘beefy’ Plastic pressures around 30,000 psi Weight – LXWXH/4 (in inches) Tooling is expensive and can take a long time to create Extrusion Process Plastic pellets or powders are heated in a plasticating unit and the melt is forced through a forming die. Continuous Process Extrusion Equipment Injection (Plasticating) Unit Frame Extrusion Materials Both amorphous and semi-crystalline are done easily Wide molecular | Chapter 9 – Plastic and Polymer Composite Fabrication Processes Injection Molding (or compression or transfer) Extrusion Thermo-Forming Blow Molding (injection blow molding with preforms or extrusion blow molding with parison) Rotational Molding (combination of 3 and 4) Molding Processes for PE: Molding Processes for Nylon (30% GF): You Tube Videos: Blow Molding: Extrusion: Injection: Thermoforming: Injection Molding – most common (60-70%) Process Plastic pellets are heated in the injection unit and forced through a runner system/gate(s) into a cavity in a mold. Batch Process Injection Molding Equipment Clamping Unit (Ejection System) Injection (Plasticating) Unit Frame Injection Molding Main functions of Plasticating unit Convey solid .
