Water Penetration Stability in Water Assisted Injection Molded Symmetric Ribs
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S.-J. Liu
Abstract
Water assisted injection molding technology has received extensive attention in recent years, due to its light weight, relatively lower resin cost per part, faster cycle time, and its flexibility in the design and manufacture of plastic parts. However, there are still some unsolved problems that confound the overall success of this technology. Unstable water penetration in molded symmetric channels is one of them. This report was to study the water penetration behavior in the water assisted injection molded symmetric cavity. Experiments were carried out on an 80-ton injection-molding machine equipped with a water injection unit. A plate cavity with symmetric water channels was used. The materials used were amorphous polystyrene and semi-crystalline polypropylene. Various processing variables were studied in terms of their influence on the water penetration behavior inside the symmetric parts: melt temperature, mold temperature, melt fill speed and fill pressure, short-shot size, water temperature and water pressure, and water injection delay time and water hold time. The effect of channel layout was also investigated. Tapered channels were found to mold parts with better penetration stability than flat channels. In addition, the penetration behaviors of water and gas in molded symmetric parts were also compared. The experimental results suggested that water penetration stability is more stable than that of gas in molded symmetric parts.
Acknowledgements
The financial support of the National Science Council of Taiwan, R.O.C. (grant number NSC93-2216-E-182-004) for this research work is gratefully acknowledged.
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You will find the article and additional material by entering the document number IPP1899 on our website at www.polymer-process.com
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© 2005 Hanser Publishers, Munich
Articles in the same Issue
- Contents
- Regular Contributed Articles
- An Improvement on Design of Sheet Extrusion Dies
- Organic-Inorganic Hybrid Material Synthesis by on Line Coupling Twin Screw Extruder with a Microwave Oven
- Water Penetration Stability in Water Assisted Injection Molded Symmetric Ribs
- A New Plasticating Model for Amorphous and Semi-crystalline Polymers in Single Screw Extruders
- Simultaneous Biaxial Stretching of Polypropylene Resins of Varying Tacticity
- Optimization of a Flat Die Including Elongational Viscosity Effects
- Experimental Study on Factors Influencing Throughput Rate and Process of Polymer-Mineral Filler Mixing in a Twin Screw Extruder
- 3D Finite Element Simulation of Processing of Generalized Newtonian Fluids in Counter-rotating and Tangential TSE and Die Combination
- Simulation of Heat Transfer in Laser Transmission Welding
- Influence of Power Law and Isothermal Simplification on the Accuracy in Single Screw Extrusion
- Melt Intercalation in Montmorillonite/Polystyrene Nanocomposites
- Experimental Investigation of the Effect of the Bubble Cone on the Cooling Jets used in the Blown Film Manufacturing Process
- Molding of Thin Sheets Using Impact Micro-injection Molding
- Rapid communications
- Ultrasonic Vibration Hot Embossing
- PPS news
- PPS news
- Seikei-kakou abstracts
- Seikei-kakou abstracts
Articles in the same Issue
- Contents
- Regular Contributed Articles
- An Improvement on Design of Sheet Extrusion Dies
- Organic-Inorganic Hybrid Material Synthesis by on Line Coupling Twin Screw Extruder with a Microwave Oven
- Water Penetration Stability in Water Assisted Injection Molded Symmetric Ribs
- A New Plasticating Model for Amorphous and Semi-crystalline Polymers in Single Screw Extruders
- Simultaneous Biaxial Stretching of Polypropylene Resins of Varying Tacticity
- Optimization of a Flat Die Including Elongational Viscosity Effects
- Experimental Study on Factors Influencing Throughput Rate and Process of Polymer-Mineral Filler Mixing in a Twin Screw Extruder
- 3D Finite Element Simulation of Processing of Generalized Newtonian Fluids in Counter-rotating and Tangential TSE and Die Combination
- Simulation of Heat Transfer in Laser Transmission Welding
- Influence of Power Law and Isothermal Simplification on the Accuracy in Single Screw Extrusion
- Melt Intercalation in Montmorillonite/Polystyrene Nanocomposites
- Experimental Investigation of the Effect of the Bubble Cone on the Cooling Jets used in the Blown Film Manufacturing Process
- Molding of Thin Sheets Using Impact Micro-injection Molding
- Rapid communications
- Ultrasonic Vibration Hot Embossing
- PPS news
- PPS news
- Seikei-kakou abstracts
- Seikei-kakou abstracts
