INTRODUCTION DIE CASTING MACHINES - North American Die

319 Pages·2015·60.28 MB·English

BASIC
OPERATOR
TRAINING
PROGRAM
Item: 685
NORTH AMERICAN DIE CASTING ASSOCIATION
Although great care has been taken to provide accurate and current information, neither the author(s)
nor the publisher, nor anyone else associated with this publication, shall be liable for any loss, damage
or liability directly or indirectly caused or alleged to be caused by this book. The material contained
herein is not intended to provide specific advice or recommendations for any specific situation.
Any opinions expressed by the author(s) are not necessarily those of NADCA.
Trademark notice: Product or corporate names may be trademarks or registered trademarks and are used
only for identification and explanation without intent to infringe nor endorse the product or corporation.
© 2015 by North American Die Casting Association, Arlington Heights, Illinois. All Rights Reserved.
Neither this book nor any parts may be reproduced or transmitted in any form or by any means,
electronic or mechanical, including photocopying, microfilming, and recording, or by any information
storage and retrieval system, without permission in writing from the publisher.
BASIC OPERATOR
TRAINING PROGRAM
ITEM: 685
2015 Latest Revision
W. Butler
PREFACE
The training program that you are now beginning is designed to give you formal training in the
die casting process. This knowledge of the process will help you determine when the process is
operating correctly and when it is in trouble and may require corrective action. Along the way, you
will learn about the die cast die, the die cast machines, the various materials and alloys that are
used on a daily basis and how they must all work together to produce an acceptable casting.
4 OPERATOR TRAINING BOOK
This training program will consist of eleven lessons of varying length.
They are:
1. Introduction to Die Casting and Safety on the Shop Floor
2. Understanding Metal Melting/Handling for Operators
3. Die Casting Machine Components and the Die Casting Cycle
4. How It Works – The Shot End
5. Why Shot Monitors Are Important
6. Die Components and Their Functions
7. Everybody Is Involved In Die Setup
8. Proper Care and Treatment of Dies During Production
9. Recognizing and Controlling Flow Defects
10. Recognizing and Controlling Porosity
11. Eliminating Solder and Flash Defects
Each chapter of this book is designed to support the information presented during the
corresponding lesson of the training program. The first lesson will set the stage for the entire
program. It is designed to tell you about the program, your role in the die casting plant and
industry, and will concentrate on safety in the industrial die casting environment.
The second lesson on metal melting and handling will discuss the alloys that are used for
the production of die castings. The various alloy compositions will be presented and your
responsibilities as an operator will be stressed.
The third lesson on the die casting machine will familiarize you with all of the components of
the die casting machine and their function. In the future, this will help you to identify and locate
components on the machine that may be a source of trouble, and let you readily communicate
about them to your supervisor and a maintenance mechanic.
OPERATOR TRAINING BOOK 5
Lesson four will focus on the shot end of the die casting machine. This part of the machine
injects the molten metal into the die at a very high rate of speed. However, this speed is
controlled in such a way as to produce acceptable castings. There is some math involved in this
section and it will be explained in detail.
Lesson five presents an important control system of modern die casting equipment, the shot
monitor. This equipment measures and controls the die casting cycle to insure quality parts and is
a critical piece of equipment for each machine operator to understand.
Lesson six will discuss the die components that are used to produce die castings. All of the
features of this important piece of equipment will be presented so that you will be able to identify
components that may need attention during production.
Lesson seven discusses die setups. There are often frequent die changes in die casting plants and
they represent lost production time. It is important to understand the need for preparation and for
proper procedures to minimize the time lost during die setups.
Lesson eight presents the care of die casting dies during production. The many details involved
in producing good parts time after time are discussed. This will be a critical part of your job as an
operator.
The last three lessons present the most common die casting defects and how they can best
be controlled. Lesson nine discusses flow defects, lesson ten presents controlling porosity in die
castings, and lesson eleven discusses how to eliminate solder and flash defects. It is important that
you be able to quickly identify casting defects and take corrective action or notify your supervisor.
6 OPERATOR TRAINING BOOK
TABLE OF CONTENTS
LESSON 1 - INTRODUCTION TO DIE CASTING & SAFETY ON THE SHOP FLOOR 9
LESSON 2 - UNDERSTANDING METAL MELTING/HANDLING FOR OPERATORS 37
LESSON 3 - DIE CASTING MACHINES AND CELL AREA EQUIPMENT 89
LESSON 4 - HOW IT WORKS - THE SHOT END 147
LESSON 5 - WHY SHOT MONITORS ARE IMPORTANT 167
LESSON 6 - DIE COMPONENTS AND THEIR FUNCTIONS 195
LESSON 7 - EVERYBODY IS INVOLVED IN DIE SETUP 231
LESSON 8 - PROPER CARE AND TREATMENT OF DIES DURING PRODUCTION 259
LESSON 9 - RECOGNIZING AND CONTROLLING FLOW DEFECTS 289
LESSON 10 - RECOGNIZING AND CONTROLLING POROSITY 307
LESSON 11 - ELIMINATING SOLDER AND FLASH DEFECTS 313
OPERATOR TRAINING BOOK 7
8 OPERATOR TRAINING BOOK
1
INTRODUCTION TO DIE CASTING
& SAFETY ON THE SHOP FLOOR
OBJECTIVES
1. To learn about the die casting industry
● To learn the history of die casting
● To learn where die castings are used
● To learn the advantages of die castings
● To learn about the jobs in the die casting industry
● To learn about the operator training program
● To learn what each lesson will cover
2. To learn about safety in the die cast environment
● To learn about the types of safety hazards
● To learn about personal protection
● To learn about general machine safety
● To learn about general die safety
● To learn about work place safety
● To learn about plant air safety
PERSPECTIVE
Metalcasting is an ancient industry. Its modern roots include sand casting, investment casting,
lost foam casting, permanent mold casting, centrifugal casting, and die casting. The word
“metalcasting” refers to the entire industry of pouring liquid metal into a mold for the purpose of
achieving a desired shape. Die casting is a particular variation of metalcasting where liquid metal
is forced into a reusable steel mold, or die, very quickly with high pressures.
Sand casting, investment casting, and lost foam casting processes all use gravity to fill the mold.
After the mold is filled, it is destroyed to remove the casting. Mold making is as important part of
these processes as is making the casting. In all these processes, gravity must fill all the casting,
consequently metal flow is slow and walls are much thicker than compared to die casting. The
cycle time is also longer because of the inability of the mold material to remove heat.
OPERATOR TRAINING BOOK 9
INTRODUCTION TO DIE CASTING
& SAFETY ON THE SHOP FLOOR
Permanent mold casting could be considered a cousin to die casting. In this process the mold
is reused, not destroyed. The process uses gravity to fill the casting, so flow control is similar
to sand casting. Metal flow is slow. Since the mold is steel, and has comparatively good thermal
conductivity, the release agents used in this process are also insulators. This is necessary, to
keep the casting from freezing periodically, and preventing filling. Machines for this process are
relatively small compared to die cast for similar sized castings.
Figure 1-1 - Permanent mold casting
Centrifugal castings are frequently made by jewelers. This is the choice for low volume castings
with a small amount of pressure. The molds are placed around the circumference of a centrifuge.
As the centrifuge spins, metal is poured in at the center and centrifugal force distributes the
metal to the molds.
Die castings are among the highest volume, mass-produced items manufactured by the
metalworking industry. Die castings are important components in thousands of consumer,
commercial and industrial products, such as automobile equipment, electrical equipment and
ordnance, general hardware, power tools, computers, and other business equipment, instruments,
toys, novelties, and a great many others to numerous to mention. In fact, die castings have
greater utility and are used in more applications than components produced by almost any other
metal forming process.
Die casting is a process involving the injection of molten metal at high pressures (as opposed to
casting by gravity pressure). It is believed to have begun sometime during the middle of the 19th
century. According to records, in 1849, Sturges patented the first manually operated machine for
casting printing type.
Another 20 years passed before the process was extended to casting other shapes. The casting of
printer’s type led to patents, which eventually resulted in development of the linotype machine by
Ottmar Mergenthaller.
10 OPERATOR TRAINING BOOK