1.1 THE BACKGROUND
Welding is a way of heating pieces of metal using electricity or a flame so that they melt and stick together. It can simply be defined as the process of joining two or more pieces of metal to make the act as a single piece. This is often done by melting the work pieces and adding a filler material to form a pool of molten material that cools to become a strong joint. Because of its strength, welding is used to join beams when constructing buildings, bridges and other structures. Welding can also be used to join pipes in pipelines, power plants at the construction sites and in home appliance. Furthermore, welding is used in shipbuilding, automobile manufacturing and repair, aerospace applications. There are many kinds of welding which include arc welding, resistance welding, gas welding among others. Emphasis will be laid on arc welding because it is the most common type of welding as well as the main aim of this project.