Injection Molding for Practitioners.

Bibliographic Details
Main Author:	Jaroschek, Christoph
Corporate Author:	Knovel (Firm)
Format:	eBook
Language:	English
Published:	München : Carl Hanser Verlag, 2024.
Subjects:	Injection molding of plastics. Matières plastiques > Moulage par injection. injection molding. Electronic books.
Online Access:	Connect to the full text of this electronic book

Table of Contents:

Intro
The Author
Preface
Contents
1 The Injection Molding Process
1.1 Process Flow
1.2 The Machine and Plant Technology
1.2.1 Clamping Unit
1.2.2 Injection Unit
1.2.3 Drive
1.2.4 Controls
2 Technical Jargon
2.1 Injection Molding Machine
2.2 Mold
2.3 Injection Molding Process
2.4 Plastic Material
3 Setting the Process Variables
3.1 Basic Information for the Initial Settings
3.1.1 Shot Weight
3.1.2 Flow Path Length
3.1.3 Average Wall Thickness
3.1.4 Plastic to Be Processed
3.1.5 Class of Molded Part
3.1.6 Projected Area of the Molded Part
3.2 Initial Setting
3.2.1 Temperature
3.2.1.1 Melt Temperature, Processing Temperature
3.2.1.2 Mold Temperature
3.2.1.3 Nozzle Temperature/Hot Runner Temperature
3.2.2 Metering
3.2.3 Injection and Holding Pressure
3.2.3.1 Injection Process
3.2.3.2 Switchover to Holding Pressure
3.2.3.3 Holding Pressure Process
3.2.4 Cooling Time
3.3 Correcting the Initial Settings
3.3.1 First Correction Step (without Holding Pressure)
3.3.2 Second Correction Step (with Holding Pressure)
3.4 Optimization of the Initial Settings
3.4.1 Incomplete Cavity Filling
3.4.2 Sink Marks
3.4.3 Flash
3.4.4 Visible Weld Lines
3.4.5 Jetting
3.4.6 Grooves (Vinyl Record Effect)
3.4.7 Surface Streaks
3.4.8 Burn Marks (Diesel Effect)
3.4.9 Dull Spots Near the Gate
3.4.10 Differences in Surface Gloss
4 Plastic Properties Relevant to Injection Molding
4.1 Flow Properties of Plastics
4.1.1 Relationship between Pressure and Velocity (Hagen-Poiseuille)
4.1.2 Viscosity
4.1.2.1 Influence of the Shear Rate on the Viscosity
4.1.2.2 Influence of Temperature on Viscosity
4.1.3 Combined Influence of Speed and Temperature (Bathtub Curve)
4.1.4 Fountain Flow
4.1.5 Troubleshooting with Flow Trace Analysis
4.2 Process Sequence for Injection and Holding Pressure
4.2.1 Relationship between Specific Pressure, Volume and Temperature (pvT Diagram)
4.2.2 Pressure-Time Graph, Pressure Curves
4.2.3 Injection Speed
4.2.4 Holding Pressure Phase
4.2.4.1 Holding Pressure Time
4.2.4.2 Holding Pressure Level
4.3 Design of Molded Parts
4.3.1 Flow-Path/Wall-Thickness Ratio
4.3.2 Filling Pattern
4.3.2.1 Weld Lines and Flow Lines
4.3.2.2 Folds
4.3.2.3 Burners/Diesel Effect
4.3.2.4 Poorly Filled Areas
4.4 Inner Properties of Plastics
4.4.1 Orientations
4.4.2 Stresses
4.4.3 Crystallization
4.5 Temperatures and Heat Processes in Plastics
4.5.1 Cooling (Calculation)
4.5.2 Cooling Properties, Weld Line Strength
4.5.3 Influence of Mold Temperature on Molded Part Dimensions
4.5.4 Temperature Equilibrium
4.5.5 Melting Temperature, Processing Temperature
4.5.6 Influence of Temperature on Demolding and General Demolding Problems
4.5.7 Dwell Time and Material Degradation