25% developed

Plastics Molding & Manufacturing

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Portrait Images of John Wesley Hyatt, pioneer of injection moulding

Many of the modern products that are a part of everyday life have gone unnoticed because they are commonly used until little thoughts are given to their existence. Have a look around in your home , workplace and such and probably you will find many things are made from plastics from small toys to the automobiles. In short, plastic play a vital role in the modern world.

The first injection moulding was invented by John and Isaiah Hyatt in 1872. The earliest of injection moulding resembles a large hypodermic needles with heated cylinder on back which forces the heated gooey materials into the awaiting mould.

Nowadays, the technology have matured and allowed for different formulations and techniques for injection moulding. Injection moulding method are suitable if there is a large number of parts are to be produced. The only disadvantages are the initial start up costs especially the injection moulding machine as well as tooling for the mould.

Below are the advantages of using plastic injection moulding:

  • High volume of mass productions rate can be achieved
  • Repeatibility of the injection moulded parts with high tolerances
  • Minimal material loss as the runner can be regrind to be used as recycled materials
  • Wide range of materials can be available for specific applications
  • Labour costs can be saved as for most automated injection moulding with robotic pickup arms: 1 operator can operate 4 injection moulding

Therefore from this Handbook of Plasting Molding and Manufacturing, it is hope that you will gain an quick overview on the plastic moulding and manufacturings.

Chapter 1: A Brief History of Plastic Manufacturing

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US114945 - Patents for Injection Moulding by John Wesley Hyatt (Diagram 1)
In Chapter 1, we would learn some of the major contributions by those brilliant man that advance the plastic fields as the current stages today

The Brief History of the Plastics 75% developed  as of Dec 30,2016

Chapter 2: Type of Plastic Process

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In the chapter 2, we will learn types of plastic moulding . Every plastic components that are moulded needs different type of manufacturing process for specific applications

Type of Plastic Moulding Process 75% developed  as of Dec 30, 2016

Chapter 3:Plastic Material

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In the chapter 3, we will learn what are the plastics are.

What is plastic ?
Plastic Moulding Charactheristic
Plastic Additives

Chapter 4:Injection Moulding Machine

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Injection moulding
In the chapter 4, we will learn the few major parts which make the injection moulding machine

Clamping System
Moulding System
Injection System

Chapter 5: Moulds for plastics

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The moulds and the mould making operation are one of the most important parts of the injection moulding process

Moulds for plastic materials
Mouldmaking operations
Moulds costing
Mould design

Chapter 6:Injection Mold Cycles

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In each injection molding cycles, there are 4 phases namely:

Clamping Phase
Injection Phase
Cooling Phase
Ejection Phase

Chapter 7:Injection Mould Process Control

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Quality Control on the moulded parts typical graphs

In Chapter 6, we will learn the key parameters to ensure the moulded plastics is of consistent quality

Temperature Control
Pressure Control
Position Control
Time Control
Quiz : Plastic Moulding Process Control

Chapter 8:Defects Occurs In Plastic Moulding Process

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Co-injection (sandwich) molded part
In Chapter 7, the common defects for moulding process usually causes from machine, mold, material and man (operator). In this section, we will learn the causes of these defects as well as solutions to solve this problems.

Plastic Moulding Defects 100% developed  as of Feb 11 ,2017
Role of Operators 25% developed  as of Feb 18 ,2017
Quiz : Plastic Moulding Defects