Gas-assist injection molding

Gas analysis, of water, 26 36-40, 41-42 Gas antisolvent (GAS) technique, 24 17 Gas-assisted injection molding (GAIM), 19 552... 

In principle, the gas-assisted injection molding process is similar to co-injection molding. Here, the second or core component is nitrogen, which is injected through a needle into the polymer melt, blowing the melt out of the way and depositing it against the mold surfaces. 

Fig. 13.31 Schematic representation of the stages of the gas-assisted injection molding process for a container handle.

Fig. 13.32 Schematic comparison of the skin thickness distributions in co- and gas-assisted injection molded parts due to the negligible gas viscosity.

Fig. 13.36 The fractional coverage during nonisothermal gas-penetration experiments in PB-300, where the gas was injected after different F0 = at/R, that is, dimensionless delay times, following the step bath temperature switchover from 60° to 0°C. [Reprinted by permission from K. W. Koelling, V. Gauri, M. Tendulkar, R. Kaminski, and O. Becker, Understanding the Controlling Mechanisms of Gas-assisted Injection Molding through Visualization, SPE ANTEC Tech Papers, 43, 3697 (1997).]...

AH/R = 8.525 K 1 for PB H-300, is known. Finally, we note that the nonisothermal temperature profiles here exist only in the absence of a phase transition, which occurs in the gas-assisted injection-molding process, at least with semicrystalline polymers. 

K. W. Koelling, V. Gauri, M. Tendulkar, R. Kaminski, and O. Becker, Understanding the Controlling Mechanisms of Gas-assisted Injection Molding through Visualization, SPE ANTEC Tech. Papers, 43, 3697-3701 (1997). 

Juntgen, T., et al., The Water Injection Molding Technique (WIT) as an Attractive Alternative and Supplement to Gas-Assisted Injection Molding (GAIM), SPE ANTEC, 2002. 

Gas-assisted injection molding is a technique used to hollow out thick sections, such as structural ribs, common in many injection molded parts. In a typical gas-assist application, a short shot of polymer is first injected into the cavity. Then a shot of gas immediately follows the polymer, pushing the melt into the unfilled regions of the... 

FIGURE 14-51 Examples of products made by gas-assisted injection molding. 

Turng, L.S. Development and application of CAE technology for the gas-assisted injection molding process. Adv. Polym. Technol. 1995, 14, 1-13. 

Important processing methods extrusion, calendering, blow molding, injection molding, gas-assisted injection molding, thermoforming, solution casting... 

GAIM gas-assisted injection molding GPEEK glass-reinforced polyetheretherketone... 

Injection Molding Alternatives. Hanser, Munich, 1998 Gas-Assist Injection Molding. Hanser, Munich, 2001 Successful Injection Molding. Hanser, Munich, 2001... 

Injection molding ABS, nylon (PA), PP, and PS Polycarbonate (PC) Power-tool housing, telephone handsets, TV cabinets, computer housing, DVDs, automotive bumpers, dashboards, syringes, kitchenware, cutlery, crates, bottle lids/closures Melt injection Variations include gas-assisted injection molding and stretch injection molding... 

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