MATL07019 2015 Plastic Part Design

General Details

Full Title
Plastic Part Design
Transcript Title
Plastic Part Design
N/A %
Subject Area
MATL - Materials
MENG - Mech. and Electronic Eng.
07 - NFQ Level 7
10 - 10 Credits
Start Term
2015 - Full Academic Year 2015-16
End Term
9999 - The End of Time
David Mulligan
Programme Membership
SG_EPOLY_S07 201500 Certificate in Polymer Processing SG_EPLYP_J07 201900 Bachelor of Engineering in Engineering in Polymer Processing

This module covers the principles and materials of plastic part design to ensure high quality parts for polymer and medical device sector.

Learning Outcomes

On completion of this module the learner will/should be able to;


Distinguish the properties of crystalline and amorphous materials to include appearance, flow, chemical resistatnce, shrinkage and deformation levels.


Explain structural design features such as wall thickness, ribs and bosses and their effects on weight and cooling requirements


Analyse injection mould design constraints to include part removal methods, draught angles, surface finish, and undercuts


Critically evaluate the injection moulding process with reference to wall thickness variation, shrinkage, deformation and gating points and their influence on the options at the part design stage


Design plastic parts giving due consideration to the characteristics of materials used, and production methods including injection, compression and blow moulding, extrustion and thermoforming


Design plastic parts taking advantage of the unique flow characteristics of the injection moulding process to include shear heating effects and melt viscosity changes throughout the injection moulding process.


Demonstrate an understanding of the documentation requiremnts for the validation for a plastic part design.

Teaching and Learning Strategies

Material will be delivered via an online teaching approach and will also include a number of practical sessions delivered by first polymer in Athlone

Module Assessment Strategies

Exam and Practical as well as project assignment

Repeat Assessments

Repeat Exams and resubmission of project

Indicative Syllabus

An Introduction to Plastic Materials

  • Historical Development
  • Fundamental Concepts
  • Molecular Weight
  • Repeat Unit Structure
  • Morphology
  • Effect of Additives
  • Mechanical Property Overview
  • Flow Property Overview
  • Advantages of Plastic Materials
  • Limitations of Plastic Materials

Review of Injection Molding Equipment

Review of the Injection Molding Process

Review of Injection Molds

  • Design Considerations for Injection Molded Parts
  • Mold Filling Considerations
  • Effect of Gate Location and Type
  • Molecular and Fiber Orientation
  • Mold Filling Pressure Drop
  • Flow Leaders and Flow Hesitation
  • Mold Filling Simulations
  • Runner Balancing and Family Molds
  • Weld or Knit Lines
  • Shrinkage and Warpage Considerations
  • Part Ejection Considerations

Mechanical Behavior of Plastic Materials

Approaching Plastic Product Development

  • Establishing End Use Requirements
  • Conceptual Design
  • Initial Candidate Material Selection Procedures
  • Design Based Upon the Materials Selected
  • Final Materials Selection
  • Manufacturing Related Design Modifications
  • Prototyping and Testing
  • Production Tooling and Manufacturing
  • Plastic Part Prototyping Techniques
  • Assembly Techniques for Injection Molded Parts

Coursework & Assessment Breakdown

Coursework & Continuous Assessment
40 %
End of Semester / Year Formal Exam
60 %

Coursework Assessment

Title Type Form Percent Week Learning Outcomes Assessed
1 Project Project Project 20 % Week 14 2,3,4,5,6
2 Practical Exam Practical Practical Evaluation 20 % Week 14 5,6,7

End of Semester / Year Assessment

Title Type Form Percent Week Learning Outcomes Assessed
1 Exam Paper Final Exam Assessment 60 % Week 14 1,2,3,4,5,6,7

Full Time Mode Workload

Type Location Description Hours Frequency Avg Workload
Laboratory Practical Not Specified Practicals 20 Twice Per Semester 2.67
Total Full Time Average Weekly Learner Contact Time 2.67 Hours

Online Learning Mode Workload

Type Location Description Hours Frequency Avg Workload
Online Lecture Not Specified Online Lecture 1 Weekly 1.00
Total Online Learning Average Weekly Learner Contact Time 1.00 Hours

Required & Recommended Book List

Recommended Reading
2010-03-01 Plastic Part Design for Injection Molding 2E: An Introduction Hanser
ISBN 1569904367 ISBN-13 9781569904367

The goal of the book is to assist the designer in the development of parts that are functional, reliable, manufacturable, and aesthetically pleasing. Because injection molding is the most widely used manufacturing process for the production of plastic parts, a full understanding of the integrated design process presented is essential to achieving economic and functional design goals. This book features over 425 drawings and photographs. Contents: Introduction to Materials. Manufacturing Considerations for Injection Molded Parts. The Design Process and Material Selection. Structural Design Considerations. Prototyping and Experimental Stress Analysis. Assembly of Injection Molded Plastic Parts. Conversion Constants.

Module Resources