3.1 Introduction
Welding consists of joining two or more pieces of metal by the application of heat and sometimes
pressure. In electric arc welding, the heat comes from an electric arc and no pressure is employed to
fuse the metal parts. In most applications of arc welding, filler metal is added to the joint which is
specially prepared in certain shapes, like a mold, to receive the molten filler metal. In some
applications, the metal parts are fused together without additional filler metal.
Since welding is related to making joints, the student should first be familiar with the terminology of
welds and joints. Not only must the names of these joints and welds be familiarized, but also the
systems by which they are technically represented. It is through the correct usage of the terminology
that we can communicate with each other in this field in the most effective and exact manner.
This chapter is the abridged version of the following CWB Modules. Students are advised to study
them for more detailed information.
Module 2 Engineering Drawings, Basic Joints and Preparation for Welding
Module 3 Symbols for Welding