The Effects of Processing Parameters on the Residual Wall Thickness Distribution at the Sharp Angle Corner of Water Assisted Injection Molded Parts
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T. Pudpong
Abstract
Water-assisted injection molding (WAIM) has been widely used for tubular plastic parts due to its advantages of relatively low cost and fast cycling time. However, the non-uniform distribution of the wall thickness, especially at the sharp corner, is still a basic problem in the WAIM process. This work presents the effects of sharp corner angles on wall thickness distribution in sections near corners for various processing conditions of the WAIM process, including melt temperature, mold temperature, water delay time, water holding time, and holding pressure. Three grades of polypropylene (PP) resins with different melt flow indices were studied using seven mold geometries that varied the angle of the sharp corner section. The wall thickness distribution at the corner sections were characterized in terms of inner and outer residual wall thicknesses, hollow core ratio, and the percentage of difference between the inner and outer wall thicknesses. In addition, computational fluid dynamic simulations with Moldflow Plastics Insight version 4.1 were performed for each sharp corner angle. It was found that the wall thickness distribution of the straight tube was more uniform than those of the curve tubes. Water injection delay time and water pressure were the major parameters that had a significant impact on the hollowed core ratios, while the percent difference between inner and outer wall thicknesses was mainly influenced by melt temperature.
References
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© 2013, Carl Hanser Verlag, Munich
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Use of the Taguchi Method for Optimization of Poly (Butylene Terephthalate) and Poly (Trimethylene Terephthalate) Blends through Injection Molding
- CFD Analysis of the Frame Invariance of the Melt Temperature Rise in a Single-screw Extruder
- Simulation Study of Thermotropic LCPs and Prediction of Normal Stress Difference at High Shear Rate
- Study on Mechanical, Thermal Properties and Morphology of Biodegradable Poly(butylene succinate)/Nano-TiO2 Composites
- Preparation and Characterization of Bamboo Fibers Coated with Titanium Urushiol and its Composite Materials with Polypropylene
- Effect of the Mandrel Rotation Speed and Inner Wall Cooling Rate on the Performance and Structure of Polypropylene Block-Copolymer Pipe
- Modification of Liquid Oxygen Compatibility of Bisphenol F Epoxy Resin
- Pressure Variation during Interfacial Instability in the Coextrusion of Low Density Polyethylene Melts
- The Effects of Processing Parameters on the Residual Wall Thickness Distribution at the Sharp Angle Corner of Water Assisted Injection Molded Parts
- The Influence of Extrusion Conditions on Mechanical and Thermal Properties of Virgin and Recycled PP, HIPS, ABS and Their Ternary Blends
- Influence of Mold Temperature on Mold Filling Behavior and Part Properties in Micro Injection Molding
- On the Pressure Dependency of the Bagley Correction
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei-Kakou Abstracts
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Use of the Taguchi Method for Optimization of Poly (Butylene Terephthalate) and Poly (Trimethylene Terephthalate) Blends through Injection Molding
- CFD Analysis of the Frame Invariance of the Melt Temperature Rise in a Single-screw Extruder
- Simulation Study of Thermotropic LCPs and Prediction of Normal Stress Difference at High Shear Rate
- Study on Mechanical, Thermal Properties and Morphology of Biodegradable Poly(butylene succinate)/Nano-TiO2 Composites
- Preparation and Characterization of Bamboo Fibers Coated with Titanium Urushiol and its Composite Materials with Polypropylene
- Effect of the Mandrel Rotation Speed and Inner Wall Cooling Rate on the Performance and Structure of Polypropylene Block-Copolymer Pipe
- Modification of Liquid Oxygen Compatibility of Bisphenol F Epoxy Resin
- Pressure Variation during Interfacial Instability in the Coextrusion of Low Density Polyethylene Melts
- The Effects of Processing Parameters on the Residual Wall Thickness Distribution at the Sharp Angle Corner of Water Assisted Injection Molded Parts
- The Influence of Extrusion Conditions on Mechanical and Thermal Properties of Virgin and Recycled PP, HIPS, ABS and Their Ternary Blends
- Influence of Mold Temperature on Mold Filling Behavior and Part Properties in Micro Injection Molding
- On the Pressure Dependency of the Bagley Correction
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei-Kakou Abstracts
