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Welding Technology Fundamentals is written for secondary and postsecondary students, apprentices,
journeymen, and individuals who wish to learn to weld.
This book covers the equipment and techniques used for the welding and cutting processes most often
employed in industry today. These processes are shielded metal arc welding, gas metal arc welding, flux
cored arc welding, gas tungsten arc welding, oxyfuel gas cutting and welding, and resistance welding.
Welding Technology Fundamentals contains information about welding careers and the physics of
welding. Technical information regarding weld inspection and testing, welder qualification, drawing
interpretation, and welding symbols is also included.
General welding safety is covered in Chapter 1. Safety information and cautions are also written into the
text wherever they apply. Safety information and cautions are printed in red, so that they will stand out.
The text is organized into nine sections. Each section is composed of one or more chapters that describe
processes, explain procedures, or present general information relating to the topic of that section. A section
can be studied independently or in sequence with other sections.
The first section provides general information about welding. The topics presented in these chapters
include welding safety, an overview of welding and cutting processes, a brief discussion of the physics
behind welding, and a close look at the different weld joints and welding positions.
Sections 2–8 present detailed information about welding and cutting processes. This study of processes
begins in Section 2 with a close look at shielded metal arc welding. The subsequent sections present
detailed information about gas metal arc welding, gas tungsten arc welding, plasma arc cutting, oxyfuel
gas processes, resistance welding, and special welding and cutting processes.
The final section discusses technical information that is of practical importance to welders. The topics
covered in these chapters includes interpreting welding symbols, inspecting and testing welds, and
welder certification. The end of the book contains several useful appendices and an extensive glossary of
technical terms.
You may begin your study of welding with any section and progress in any desired sequence from
section to section. However, when you use the Laboratory Manual for Welding Technology Fundamentals,
we recommend that Chapter 33, Welding Symbols, be studied early. Welding symbols are used in the
Laboratory Manual to describe the sample joints and welds for each job assignment. Before attempting any
welding process that uses a pressurized gas, Chapters 20 and 21 should be studied.
Welding Technology Fundamentals is written in an easy-to-read and understandable style. All welding terms
used are those approved by the American Welding Society (AWS). In cases where nonstandard terms are used
by some people in the trade, such terms are often given in parentheses after the correct AWS term. The book is
extensively illustrated with drawings and photographs to show the various processes or welding techniques.
Many tables and charts are provided to help you select the proper variable values required to make a
good weld. Photographs of industrial welding applications have been used, along with photographs of
practice welds in progress. Equivalent SI metric measurement units are shown in parentheses following US
conventional measurements.
You should read the caption accompanying each illustration, since the caption often gives information that
is not covered in the text. Review questions are provided at the end of each chapter to test your knowledge of
the information covered. In most chapters, practice exercises are provided to test your skills as a student
welder in completing various welding tasks.
It is our sincere hope that Welding Technology Fundamentals will help you progress in an organized
manner toward a mastery of the essential welding skills.
William A. Bowditch
Kevin E. Bowditch
Mark A. Bowditch
IntroductionnoitcudortnI Introduction