CHAPTER 7
INTRODUCTION TO WELDING AND CUTTING
LEARNING OBJECTIVES
Upon completion of this chapter, you will be able to do the following:
Identify the principle welding processes and define terms used in basic
welding.
Identify the various welding symbols.
Describe the types and techniques of edge preparation in welding.
Describe the purpose of temperature control during and after the welding
process has been performed.
Describe the pipe welding process, and identify the different classes of piping.
Identify the principle cutting processes.
Name the important publications concerning military standards and
qualification tests with which a welder should be familiar.
WELDING PROCESSES
INTRODUCTION
A master chart of welding processes is shown in
One of the primary requirements for Hull
figure 7-1. The term WELDING PROCESS means
Maintenance Technicians is to make various metal
that you heat metal parts to a temperature that is
objects and structures. Most of these will require
high enough to join the metal parts by coalescence.
welding and cutting metal. Study and practical
It is done with or without the use of pressure or by
experience are both necessary to become an expert
the pressure alone, and it can be done with or
welder. This chapter contains essential background
without the use of filler metal. Coalescence means
information that will help you to learn the welding
the growing together, or growth into one body, of
processes and to qualify for advancement. Most of
There are two basic
the base metal parts.
the terms, phrases, and processes discussed in this
requirements for coalescence: heat and intimacy of
chapter are standardized, and are used in the Navy
contact.
as well as by civilians in the welding trades. At
times, the information in this chapter may seem
HEAT
complex, but you need a thorough knowledge of it
to perform the duties of your job. Study this
The welding processes differ depending on the
chapter carefully so you can effectively assist skilled
source of heat, the manner in which heat is applied
welders and eventually become a good welder
or generated, and the intensity of the heat. The
yourself.
source of heat may be the combustion of a fuel gas
7-1