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| Preface | |
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| Nomenclature | |
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| Introduction | |
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| Overview of the Injection Molding Process | |
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| Mold Functions | |
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| Mold Structures | |
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| External View of Mold | |
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| View of Mold during Part Ejection | |
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| Mold Section and Function | |
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| Other Common Mold Types | |
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| Three Plate, Multi-Cavity Family Mold | |
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| Hot Runner, Multi-Gated, Single Cavity Mold | |
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| Comparison | |
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| The Mold Development Process | |
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| Chapter Review | |
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| Plastic Part Design | |
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| The Product Development Process | |
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| Product Definition | |
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| Product Design | |
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| Business and Production Development | |
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| Scale-Up and Launch | |
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| Role of Mold Design | |
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| Design Requirements | |
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| Application Engineering Information | |
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| Production Data | |
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| End Use Requirements | |
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| Product Design Methodology | |
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| Plastic Material Properties | |
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| Design for Injection Molding | |
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| Uniform Wall Thickness | |
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| Rib Design | |
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| Boss Design | |
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| Corner Design | |
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| Surface Finish and Textures | |
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| Draft | |
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| Undercuts | |
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| Chapter Review | |
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| Mold Cost Estimation | |
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| The Mold Quoting Process | |
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| Cost Drivers for Molded Parts | |
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| Effect of Production Quantity | |
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| Break-Even Analysis | |
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| Mold Cost Estimation | |
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| Cavity Cost Estimation | |
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| Cavity Set Cost | |
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| Cavity Materials Cost | |
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| Cavity Machining Cost | |
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| Cavity Discount Factor | |
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| Cavity Finishing Cost | |
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| Mold Base Cost Estimation | |
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| Mold Customization | |
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| Part Cost Estimation | |
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| Mold Cost per Part | |
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| Material Cost per Part | |
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| Processing Cost per Part | |
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| Defect Cost per Part | |
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| Chapter Review | |
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| Mold Layout Design | |
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| Parting Plane Design | |
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| Determine Mold Opening Direction | |
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| Determine Parting Line | |
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| Parting Plane | |
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| Shut-Offs | |
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| Cavity and Core Insert Creation | |
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| Height Dimension | |
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| Length and Width Dimensions | |
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| Adjustments | |
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| Mold Base Selection | |
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| Cavity Layouts | |
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| Mold Base Sizing | |
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| Molding Machine Compatibility | |
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| Mold Base Suppliers | |
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| Mold Material Selection | |
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| Strength vs. Heat Transfer | |
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| Hardness vs. Machinability | |
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| Mold-Maker's Cost vs. Molder's Cost | |
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| Material Summary | |
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| Chapter Review | |
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| Cavity Filling Analysis and Design | |
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| Overview | |
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| Objectives in Cavity Filling | |
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| Complete Filling of Mold Cavities | |
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| Avoid Uneven Filling or Over-Packing | |
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| Control the Melt Flow | |
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| Viscous Flow | |
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| Shear Stress, Shear Rate, and Viscosity | |
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| Pressure Drop | |
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| Rheological Behavior | |
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| Newtonian Model | |
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| Power Law Model | |
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| Validation | |
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| Cavity Filling Analyses and Designs | |
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| Estimating the Processing Conditions | |
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| Estimating the Filling Pressure and Minimum Wall Thickness | |
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| Estimating Clamp Tonnage | |
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| Predicting Filling Patterns | |
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| Designing Flow Leaders | |
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| Chapter Review | |
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| Feed System Design | |
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| Overview | |
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| Objectives in Feed System Design | |
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| Conveying the Polymer Melt from Machine to Cavities | |
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| Impose Minimal Pressure Drop | |
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| Consume Minimal Material | |
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| Control Flow Rates | |
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| Feed System Types | |
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| Two-Plate Mold | |
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| Three-Plate Mold | |
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| Hot Runner Molds | |
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| Feed System Analysis | |
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| Determine Type of Feed System | |
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| Determine Feed System Layout | |
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| Estimate Pressure Drops | |
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| Calculate Runner Volume | |
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| Optimize Runner Diameters | |
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| Balance Flow Rates | |
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| Estimate Runner Cooling Times | |
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| Estimate Residence Time | |
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| Practical Issues | |
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| Runner Cross-Sections | |
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| Sucker Pins | |
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| Runner Shut-Offs | |
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| Standard Runner Sizes | |
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| Steel Safe Designs | |
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| Chapter Review | |
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| Gating Design | |
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| Objectives of Gating Design | |
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| Connecting the Runner to the Mold Cavity | |
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| Provide Automatic De-Gating | |
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| Provide Aesthetic De-Gating | |
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| Avoid Excessive Shear or Pressure Drop | |
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| Control Pack Times | |
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| Common Gate Designs | |
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| Sprue Gate | |
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| Pin-Point Gate | |
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| Edge Gate | |
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| Tab Gate | |
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| Fan Gate | |
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| Flash/Diaphragm Gate | |
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| Tunnel/Submarine Gate | |
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| Thermal Gate | |
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| Valve Gate | |
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| The Gating Design Process | |
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| Determine Type of Gate | |
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| Calculate Shear Rates | |
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| Calculate Pressure Drop | |
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| Calculate Gate Freeze Time | |
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| Adjust Dimensions | |
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| Chapter Review | |
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| Venting | |
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| Venting Design Objectives | |
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| Release Compressed Air | |
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| Contain Plastic Melt | |
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| Minimize Maintenance | |
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| Venting Analysis | |
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| Estimate Air Displacement and Rate | |
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| Identify Number and Location of Vents | |
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| Specify Vent Dimensions | |
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| Venting Designs | |
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| Vents on Parting Plane | |
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| Vents around Ejector Pins | |
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| Vents in Dead Pockets | |
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| Chapter Review | |
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| Cooling System Design | |
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| Objectives in Cooling System Design | |
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| Maximize Heat Transfer Rates | |
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| Maintain Uniform Wall Temperature | |
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| Minimize Mold Cost | |
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| Minimize Volume and Complexity | |
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| Minimize Stress and Corrosion | |
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| Facilitate Mold Usage | |
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| The Cooling System Design Process | |
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| Calculate the Required Cooling Time | |
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| Evaluate Required Heat Transfer Rate | |
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| Assess Coolant Flow Rate | |
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| Assess Cooling Line Diameter | |
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| Select Cooling Line Depth | |
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| Select Cooling Line Pitch | |
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| Cooling Line Routing | |
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| Cooling System Designs | |
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| Cooling Line Networks | |
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| Cooling Inserts | |
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| Conformal Cooling | |
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| Highly Conductive Inserts | |
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| Cooling of Slender Cores | |
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| Cooling Insert | |
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| Baffles | |
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| Bubblers | |
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| Heat Pipes | |
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| Conductive Pin | |
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| Interlocking Core with Air Channel | |
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| One-Sided Heat Flow | |
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| Chapter Review | |
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| Shrinkage and Warpage | |
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| The Shrinkage Analysis Process | |
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| Estimate Process Conditions | |
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| Model Compressibility Behavior | |
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| Assess Volumetric Shrinkage | |
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| Evaluate Isotropic Linear Shrinkage | |
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| Evaluate Anisotropic Shrinkage | |
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| Assess Shrinkage Range | |
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| Establishing Final Shrinkage Recommendations | |
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| Shrinkage Analysis and Validation | |
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| Numerical Simulation | |
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| "Steel Safe" Mold Design | |
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| Processing Dependence | |
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| Semi-Crystalline Plastics | |
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| Effect of Fillers | |
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| Warpage | |
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| Sources of Warpage | |
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| Warpage Avoidance Strategies | |
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| Chapter Review | |
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| Ejection System Design | |
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| Objectives in Ejection System Design | |
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| Allow Mold to Open | |
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| Transmit Ejection Forces to Moldings | |
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| Minimize Distortion of Moldings | |
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| Actuate Quickly and Reliably | |
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| Minimize Cooling Interference | |
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| Minimize Impact on Part Surfaces | |
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| Minimize Complexity and Cost | |
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| The Ejector System Design Process | |
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| Identify Mold Parting Surfaces | |
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| Estimate Ejection Forces | |
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| Determine Ejector Push Area and Perimeter | |
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| Specify Type, Number, and Size of Ejectors | |
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| Layout Ejectors | |
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| Detail Ejectors and Related Components | |
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| Ejector System Analyses and Designs | |
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| Ejector Pins | |
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| Ejector Blades | |
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| Ejector Sleeves | |
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| Stripper Plates | |
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| Elastic Deformation around Undercuts | |
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| Core Pulls | |
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| Slides | |
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| Early Ejector Return Systems | |
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| Advanced Ejection Systems | |
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| Chapter Review | |
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| Structural System Design | |
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| Objectives in Structural System Design | |
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| Minimize Stress | |
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| Minimize Mold Deflection | |
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| Minimize Mold Size | |
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| Analysis and Design of Plates | |
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| Plate Compression | |
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| Plate Bending | |
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| Support Pillars | |
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| Shear Stress in Side Walls | |
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| Interlocks | |
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| Stress Concentrations | |
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| Analysis and Design of Cores | |
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| Axial Compression | |
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| Compressive Hoop Stresses | |
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| Core Deflection | |
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| Fasteners | |
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| Fits | |
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| Socket Head Cap Screws | |
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| Dowels | |
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| Review | |
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| Mold Technologies | |
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| Introduction | |
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| Coinjection Molds | |
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| Coinjection Process | |
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| Coinjection Mold Design | |
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| Gas Assist/Water Assist Molding | |
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| Insert Molds | |
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| Low Pressure Compression Molding | |
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| Insert Mold with Wall Temperature Control | |
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| Lost Core Molding | |
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| Injection Blow Molds | |
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| Injection Blow Molding | |
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| Multilayer Injection Blow Molding | |
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| Multi-Shot Molds | |
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| Overmolding | |
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| Core-Back Molding | |
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| Multi-Station Mold | |
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| Feed Systems | |
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| Insulated Runner | |
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| Stack Molds | |
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| Branched Runners | |
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| Dynamic Melt Control | |
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| Mold Wall Temperature Control | |
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| Pulsed Cooling | |
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| Conduction Heating | |
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| Induction Heating | |
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| Managed Heat Transfer | |
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| In-Mold Labeling | |
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| Statically Charged Film | |
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| Indexed Film | |
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| Ejection | |
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| Split Cavity Molds | |
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| Collapsible Cores | |
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| Rotating Cores | |
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| Reverse Ejection | |
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| Review | |
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| Appendix | |
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| Plastic Material Properties | |
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| Mold Material Properties | |
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| Non-Ferrous Metals | |
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| Common Mold Steels | |
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| Other Mold Steels | |
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| Notes | |
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| Properties of Coolants | |
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| Statistical Labor Data | |
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| United States Labor Rates | |
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| International Labor Rates | |
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| Trends in International Manufacturing Costs | |
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| Unit Conversions | |
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| Length Conversions | |
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| Mass/Force Conversions | |
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| Pressure Conversions | |
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| Flow Rate Conversions | |
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| Viscosity Conversions | |
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| Energy Conversions | |
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| Advanced Derivations | |
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| Bibliography | |
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| Subject Index | |