Thin-wall injection molding

Other HDPE formulations include a high-flow HDPE that is suited to injection molding thin-wall products like food containers, drink cups,... 

Injection-molded polycarbonate sheet for car windows requires injection molding thin-wall large panes up to 11 ft with minimum molded-in stress. They can be injection-compression-molded, with overmolded frames, and removed by a press-mounted six-axis articulating robot [11]. 

Controlled rheology injection molding, thin-wall... 

Figure 4. Photograph of injection-molded thin-walled parts (rings). Molded in Italy by Cadauta, S. Sebastiano da Po, Torino (sample B). Total width 310 mm, total mass, including runner 25 g, mass of each part 2 g (cylindrical, diameter 25 mm, height 25 mm, wall thickness 1 nun). These rings are normally made of PP.

THERMAL PROPERTIES AND STRUCTURE OF INJECTION MOLDED THIN-WALL PRODUCTS OF POLYPROPYLENE/BORON-NITRIDE COMPOSITES... 

In creating a process window for the combination of material, machine and heater used in this study, the first consideration was the moldability, which was dictated by the maximum injection pressure and the maximum clamp force. No changes in melt and mold temperature, injection velocity, or gate size could remedy this situation. Thus, an injection molding machine with higher injection speeds, pressures and clamp force was required to mold thin-walled syndiotactic polystyrene. 

Processing methods extrusion, injection molding, blow molding, thin-wall injection molding, injection stretch blow molding, sheet extrusion, blown fihn, cast film, rotomolding, and thermo-forming... 

Thin wall plastics are used to hot fill (injection and blow molded bottles, thermoformed containers, etc.) without sagging during filling and maintaining mechanical properties such as impact strength and stiffness in temperatures from at least —40°F to 250°F (—40°C to 120°C). Plastic used includes special grades of PEN, PET, PP, PS, and PVC. 

Soluble core molding The soluble core technology (SCT) is called by different names such as soluble fusible metal core technology (FMCT), fusible core, lost-core, and lost-wax techniques (3). In this process, a core [usually molded of a low melting alloy (eutectic mixture) but can also use water soluble TPs, wax formulations, etc.] is inserted into a mold such as an injection molding mold. This core can be of thin wall or solid construction. 

Because PTFE melts at such a high temperature and the melt is very viscous, it is difficult to work by conventional plastics techniques such as injection molding or extrusion. It is usually formed into useful shapes by sintering at about 380 °C sometimes liquid alkanes are used as a carrier, but the product then tends to be porous (this emerges as a serious problem when thin-walled objects are machined out of PTFE stock). Accordingly, several fluorocarbon thermoplastics have been developed that have lower melt viscosities, at the expense of somewhat poorer thermal and mechanical properties than PTFE. For example, the thermoplastic FEP (fluori-nated ethylene propylene), made by copolymerization of F2C=CF2 and... 

PVC has a unique ability to be compounded with a wide variety of additives, making it possible to produce materials that range from flexible elastomers to rigid compounds, that are virtually unbreakable. Compounds arc also made that have stiff melts for profile extrusion or low viscosity melts fur thin-walled injection molding. 

Numerous housings, electrical enclosures, and cabinets are injection-molded from rigid PVC. These take advantage of PVC s outstanding UL flammability ratings and easy molding into thin-walled parts. 

Perform a dimensional analysis on the thin wall injection molding scaling problem of Example 4.8 and find the dimensionless groups used in the example. 

S. Garcia, A. Roldan, J.R Hernandez-Ortiz, and T.A. Osswald. Dimensional analysis and scaling approach for thin wall injection molding. In ANTEC 2004, pages 3428-3422. SPE-ANTEC, 2004. 

Injection-Molded Products. Numerous housings, electrical enclosures, and cabinets are injection-molded from rigid PVC. These take advantage of PVC s outstanding UL flammability ratings and easy molding into thin-walled parts. PVC has developed melt flow capabilities to the point where it competes with essentially any other flame-retarded engineering thermoplastic and molds easier than most. 

Pipe fittings require quite high tensile and creep resistance they are thus molded from compounds that have less melt flow than for thin-walled housings. Plasticized compounds are injection-molded into a variety of parts requiring elastomeric properties. 

Coxe, M., et al., The Establishment of a Processing Window for Thin-Wall Injection Molding of Syndiotactic Polystyrene, SPE ANTEC, 2000. 

Cha, S., etal., 3-D Simulation of Thin-Wall Injection molded Parts by CAE, SPE IMD News, May 2002. 

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