Welding Processes:

Welding is a technique of joining metals. In the ideal weld ,there is complete continuity among the parts joined and every part of the joint is indistinguishable from the metal in which the joint is built. Although this ideal weld is never attained in practice. However welds that give satisfactory service may be made in many ways. Every welding procedure is not equally appropriate for each metal, type of joint or application. The skill of the welding engineer consists in the recognition of the necessary requirements which a specific weld must satisfy and the choice of the suitable welding process.

In this unit we are going to explain what are the fundamental requirements for joining two materials. We are going to explain the various welding processes such as :

A. Shielded Metal Arc Welding (SMAW); Also called as MMAW (Manual Metal Arc Welding),

B. Gas Tungsten Arc Welding (GTAW),

C. Submerged Arc Welding (SAW),

D. Gas Metal Arc Welding (GMAW),

E. Plasma Arc Welding (PAW).

We are also going to introduce Gas Welding.

Objectives

After studying this unit, you must be able to know

• the fundamental needs in welding,
• various arc welding procedure, and
• process capabilities , parameters and limitations.