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Designing plastic parts for assembly /

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"For over 27 years, "Designing Plastic Parts for Assembly" has been the definitive guide for both seasoned part designers and novices to the field, facilitating cost-effective design decisions and ensuring that the plastic parts and products will stand up under use.The detailed yet si...

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Bibliographic Details
Main Author: Tres, Paul A. (Author)
Corporate Author: ScienceDirect (Online service)
Format: eBook
Language:English
Published: Munich, Germany ; Cincinnati, OH : Hanser Publishers, [2021]
Edition:9th edition
Subjects:
Plastics > Molding.
Machine parts.
Machines > Pièces.
Machine parts
Plastics > Molding
Electronic books.
Online Access:Connect to the full text of this electronic book
Table of Contents:
  • Intro
  • Contents
  • Foreword to the Ninth Edition
  • Preface to the Ninth Edition
  • Foreword to the First Edition
  • Preface to the First Edition
  • Acknowledgments
  • 1 Understanding Plastic Materials
  • 1.1 Basic Resins
  • 1.1.1 Thermoplastics
  • 1.1.2 Thermosets
  • 1.2 Basic Structures
  • 1.2.1 Crystalline
  • 1.2.2 Amorphous
  • 1.2.3 Liquid Crystal Polymer (LCP)
  • 1.2.4 New Polymer Technologies
  • 1.2.4.1 Inherently Conductive Polymers (ICP)
  • 1.2.4.2 Electro-Optic Polymers (EOP)
  • 1.2.4.3 Biopolymers
  • 1.3 Homopolymer vs. Copolymer
  • 1.4 Reinforcements
  • 1.5 Fillers
  • 1.5.1 Glass Spheres
  • 1.5.1.1 Microsphere Properties
  • 1.5.1.2 Compounding
  • 1.5.1.3 Injection Molding
  • 1.5.1.4 Mechanical Properties in Injection-Molded Thermoplastic Applications
  • 1.6 Additives
  • 1.7 Physical Properties
  • 1.7.1 Density and Specific Gravity
  • 1.7.2 Elasticity
  • 1.7.2.1 Case History: Elasticity and Denier
  • 1.7.3 Plasticity
  • 1.7.4 Ductility
  • 1.7.5 Toughness
  • 1.7.6 Brittleness
  • 1.7.7 Notch Sensitivity
  • 1.7.8 Isotropy
  • 1.7.9 Anisotropy
  • 1.7.10 Water Absorption
  • 1.7.11 Mold Shrinkage
  • 1.8 Mechanical Properties
  • 1.8.1 Normal Stress
  • 1.8.2 Normal Strain
  • 1.8.3 Stress-Strain Curve
  • 1.9 Creep
  • 1.9.1 Introduction
  • 1.9.2 Creep Experiments
  • 1.9.3 Creep Curves
  • 1.9.4 Stress-Relaxation
  • 1.10 Impact Properties
  • 1.11 Thermal Properties
  • 1.11.1 Melting Point
  • 1.11.2 Glass Transition Temperature
  • 1.11.3 Heat Deflection Temperature
  • 1.11.4 Coefficient of Thermal Expansion
  • 1.11.5 Thermal Conductivity
  • 1.11.6 Thermal Influence on Mechanical Properties
  • 1.11.7 Case History: Planetary Gear Life Durability
  • 2 Understanding Safety Factors
  • 2.1 What Is a Safety Factor
  • 2.2 Using the Safety Factors
  • 2.2.1 Design Safety Factors
  • 2.2.1.1 Design Static Safety Factor
  • 2.2.1.2 Design Dynamic Safety Factor.
  • 2.2.1.3 Design Time-Related Safety Factor
  • 2.2.2 Material Properties Safety Factor
  • 2.2.3 Processing Safety Factors
  • 2.2.4 Operating Condition Safety Factor
  • 3 Strength of Material for Plastics
  • 3.1 Tensile Strength
  • 3.1.1 Proportional Limit
  • 3.1.2 Elastic Stress Limit
  • 3.1.3 Yield Stress
  • 3.1.4 Ultimate Stress
  • 3.2 Compressive Stress
  • 3.3 Shear Stress
  • 3.4 Torsion Stress
  • 3.5 Elongations
  • 3.5.1 Tensile Strain
  • 3.5.2 Compressive Strain
  • 3.5.3 Shear Strain
  • 3.6 True Stress and Strain vs. Engineering Stress and Strain
  • 3.7 Poisson's Ratio
  • 3.8 Modulus of Elasticity
  • 3.8.1 Young's Modulus
  • 3.8.2 Tangent Modulus
  • 3.8.3 Secant Modulus
  • 3.8.4 Creep (Apparent) Modulus
  • 3.8.5 Shear Modulus
  • 3.8.6 Flexural Modulus
  • 3.8.7 The Use of Various Moduli
  • 3.9 Stress Relations
  • 3.9.1 Introduction
  • 3.9.2 Experiment
  • 3.9.3 Equivalent Stress
  • 3.9.4 Maximum Normal Stress
  • 3.9.5 Maximum Normal Strain
  • 3.9.6 Maximum Shear Stress
  • 3.9.7 Maximum Deformation Energy
  • 3.10 ABCs of Plastic Part Design
  • 3.10.1 Constant Wall
  • 3.10.2 Fillets
  • 3.10.3 Boss Design
  • 3.10.4 Rib Design
  • 3.10.5 Case History: Ribs
  • 3.11 Automotive Case History: Airbag Module's Plastic Cover Assembly
  • 3.12 Conclusions
  • 4 Nonlinear Considerations
  • 4.1 Material Considerations
  • 4.1.1 Linear Material
  • 4.1.2 Nonlinear Materials
  • 4.2 Geometry
  • 4.2.1 Linear Geometry
  • 4.2.2 Nonlinear Geometry
  • 4.3 Finite Element Analysis (FEA)
  • 4.3.1 FEA Method Application
  • 4.3.2 Using FEA Method
  • 4.3.3 Most Common FEA Codes
  • 4.4 Conclusions
  • 5 Welding Techniques for Plastics
  • 5.1 Ultrasonic Welding
  • 5.1.1 Ultrasonic Equipment
  • 5.1.2 Horn Design
  • 5.1.3 Ultrasonic Welding Techniques
  • 5.1.4 Control Methods
  • 5.1.4.1 Common Issues with Welding
  • 5.1.4.2 Joint Design
  • 5.1.4.3 Butt Joint Design.
  • 5.1.4.4 Shear Joint Design
  • 5.1.4.5 Torsional Ultrasonic Welding
  • 5.1.4.6 Case History: Welding Dissimilar Polymers
  • 5.2 Ultrasonic (Heat) Staking
  • 5.2.1 Standard Stake Design
  • 5.2.2 Flush Stake Design
  • 5.2.3 Spherical Stake Design
  • 5.2.4 Hollow (Boss) Stake Design
  • 5.2.5 Knurled Stake Design
  • 5.3 Ultrasonic Spot Welding
  • 5.4 Ultrasonic Swaging
  • 5.5 Ultrasonic Stud Welding
  • 5.6 Spin Welding
  • 5.6.1 Process
  • 5.6.2 Equipment
  • 5.6.3 Welding Parameters
  • 5.6.4 Joint Design
  • 5.7 Hot Plate Welding
  • 5.7.1 Process
  • 5.7.2 Joint Design
  • 5.8 Vibration Welding
  • 5.8.1 Process
  • 5.8.2 Equipment
  • 5.8.3 Joint Design
  • 5.8.4 Common Issues with Vibration Welding
  • 5.9 Electromagnetic Welding
  • 5.9.1 Equipment
  • 5.9.2 Process
  • 5.9.3 Joint Design
  • 5.10 Radio Frequency (RF) Welding
  • 5.10.1 Equipment
  • 5.10.2 Process
  • 5.11 Laser Welding
  • 5.11.1 Equipment
  • 5.11.2 Process
  • 5.11.3 Noncontact Welding
  • 5.11.4 Transmission Welding
  • 5.11.5 Intermediate Film &amp
  • ClearWeld™ Welding
  • 5.11.6 Polymers
  • 5.11.7 Applications
  • 5.12 Conclusion
  • 6 Press Fitting
  • 6.1 Introduction
  • 6.2 Definitions and Notations
  • 6.3 Geometric Definitions
  • 6.4 Safety Factors
  • 6.5 Creep
  • 6.6 Loads
  • 6.7 Press Fit Theory
  • 6.8 Design Algorithm
  • 6.9 Case History: Plastic Shaft and Plastic Hub
  • 6.9.1 Shaft and Hub Made of Different Polymers
  • 6.9.2 Safety Factor Selection
  • 6.9.3 Material Properties
  • 6.9.4 Shaft Material Properties at 23°C
  • 6.9.4.1 Shaft Material Properties at 93°C
  • 6.9.4.2 Creep Curves at 23°C
  • 6.9.4.3 Creep at 93°C
  • 6.9.4.4 Pulley at 23°C
  • 6.9.4.5 Pulley at 93°C
  • 6.9.4.6 Creep, Pulley at 23°C
  • 6.9.4.7 Creep, Pulley at 93°C
  • 6.10 Solutions: Plastic Shaft, Plastic Hub
  • 6.10.1 Case A
  • 6.10.2 Case B
  • 6.10.3 Case C
  • 6.10.4 Case D.
  • 6.11 Case History: Metal Ball Bearing and Plastic Hub
  • 6.11.1 Fusible Core Injection Molding
  • 6.11.2 Upper Intake Manifold Background
  • 6.11.3 Design Algorithm
  • 6.11.4 Material Properties
  • 6.11.4.1 CAMPUS
  • 6.11.5 Solution
  • 6.11.5.1 Necessary IF at Ambient Temperature
  • 6.11.5.2 IF Available at 118°C
  • 6.11.5.3 IF Verification at -40°C
  • 6.11.5.4 Verification of Stress Level at -40°C, Time = 0
  • 6.11.5.5 Stress Level at -40°C, Time = 5,000 h
  • 6.11.5.6 Stress Level at 23°C, Time = 5,000 h
  • 6.11.5.7 Stress Level at 118°C, Time = 5,000 h
  • 6.12 Successful Press Fits
  • 6.13 Conclusion
  • 7 Living Hinges
  • 7.1 Introduction
  • 7.2 Classic Design for PP and PE
  • 7.3 Common Living Hinge Design
  • 7.4 Basic Design for Engineering Plastics
  • 7.5 Living Hinge Design Analysis
  • 7.5.1 Elastic Strain Due to Bending
  • 7.5.1.1 Assumptions
  • 7.5.1.2 Geometric Conditions
  • 7.5.1.3 Strain Due to Bending
  • 7.5.1.4 Stress Due to Bending
  • 7.5.1.5 Closing Angle of the Hinge
  • 7.5.1.6 Bending Radius of the Hinge
  • 7.5.2 Plastic Strain Due to Pure Bending
  • 7.5.2.1 Assumptions
  • 7.5.2.2 Strain Due to Bending
  • 7.5.3 Plastic Strain Due to a Mixture of Bending and Tension
  • 7.5.3.1 Tension Strain
  • 7.5.3.2 Bending Strain
  • 7.5.3.3 Neutral Axis Position
  • 7.5.3.4 Hinge Length
  • 7.5.3.5 Elastic Portion of the Hinge Thickness
  • 7.6 Computer Flow Chart
  • 7.6.1 Computer Notations
  • 7.7 Computer Flow Chart Equations
  • 7.8 Example: Case History
  • 7.8.1 World-Class Connector
  • 7.8.1.1 Calculations for the "Right Way" Assembly
  • 7.8.1.2 Calculations for the "Wrong Way" Assembly
  • 7.8.2 Comparison Material
  • 7.8.2.1 "Right Way" Assembly
  • 7.8.2.2 "Wrong Way" Assembly
  • 7.8.3 Ignition Cable Bracket
  • 7.8.3.1 Initial Design
  • 7.8.3.2 Improved Design
  • 7.9 Processing Errors for Living Hinges
  • 7.10 Coined Hinges.
  • 7.11 Oil-Can Designs
  • 7.12 Conclusion
  • 7.13 Exercise
  • 8 Snap Fitting
  • 8.1 Introduction
  • 8.2 Material Considerations
  • 8.3 Design Considerations
  • 8.3.1 Safety Factors
  • 8.4 Snap Fit Theory
  • 8.4.1 Notations
  • 8.4.2 Geometric Conditions
  • 8.4.3 Stress/Strain Curve and Formulae
  • 8.4.4 Instantaneous Moment of Inertia
  • 8.4.5 Angle of Deflection
  • 8.4.6 Integral Solution
  • 8.4.7 Equation of Deflection
  • 8.4.8 Integral Solution
  • 8.4.9 Maximum Deflection
  • 8.4.10 Self-Locking Angle
  • 8.5 Case History: One-Way Continuous Beam with Rectangular Cross Section
  • 8.5.1 Geometrical Model
  • 8.6 Annular Snap Fits
  • 8.6.1 Case History: Annular Snap Fit, Rigid Beam with Soft Mating Part
  • 8.6.2 Notations
  • 8.6.3 Geometric Definitions
  • 8.6.4 Material Selections and Properties
  • 8.6.5 Basic Formulas
  • 8.6.6 Angle of Assembly
  • 8.6.7 Case History: Digital Wristwatch
  • 8.7 Torsional Snap Fits
  • 8.7.1 Notations
  • 8.7.2 Basic Formulae
  • 8.7.3 Material Properties
  • 8.7.4 Solution
  • 8.8 Case History: Injection Blow Molded Bottle Assembly
  • 8.9 Tooling
  • 8.10 Case History: Snap Fits That Kill
  • 8.11 Assembly Procedures
  • 8.12 Issues with Snap Fitting
  • 8.13 Serviceability
  • 8.14 Exercise
  • 8.14.1 Solution
  • 8.15 Conclusions
  • 9 Bonding
  • 9.1 Failure Theories
  • 9.2 Surface Energy
  • 9.3 Surface Treatment
  • 9.4 Types of Adhesives
  • 9.5 Advantages and Limitations of Adhesives
  • 9.6 Stress Cracking in Bonded Joints of Adhesives
  • 9.7 Joint Design
  • 9.8 Conclusion
  • 10 In-Mold Assembly
  • 10.1 Overmolding
  • 10.2 In-Mold Assembly
  • 10.3 Joint Design
  • 10.4 Tool Design
  • 10.5 Case Histories: Automotive IMA
  • 10.6 Conclusion
  • 11 Fasteners
  • 11.1 Thread Forming
  • 11.2 Case History: Automotive Undercarriage Splash Shield
  • 11.3 Thread Cutting
  • 11.4 Case History: Thermal Management Module
  • 11.5 Conclusion.