Welding:
Welding is a process of joining two metal pieces by the application of heat. Welding is the least expensive process and widely used now a days in fabrication. Welding joints different metals with the help of a number of processes in which heat is supplied either electrically or by mean of a gas torch. Different welding processes are used in the manufacturing of Auto mobiles bodies, structural work, tanks, and general machine repair work. In the industries , welding is used in refineries and pipe line fabrication. It may be called a secondary manufacturing process.
Classification of welding processes:
There are about 35 different welding and brazing process and several soldering methods, in use by the industry today. There are various ways of classifying the welding for example, they may be classified on the basis of source of heat(flames ,arc etc.)
In general various welding processes are classified as follows.
1: Gas Welding
(a): Air Acetylene
(b): Oxy Acetylene
(c): Oxy Hydrogen Welding
2: Arc Welding
(a): Carbon Arc welding
(b); Plasma Arc welding
(c): Shield Metal Arc Welding
(d): T.I.G. ( Tungsten Inert Gas Welding)
(e): M.I.G. ( Metal Inert Gas Welding)
3: Resistance Welding:
(a): Spot welding
(b): Seam welding
(c): Projection welding
(d): Resistance Butt welding
(e): Flash Butt welding
4: Solid State
(a): Cold welding
(b): Diffusion welding
(c): Forge welding
(d): Fabrication welding
(e): Hot pressure welding
(f): Roll welding
5: Thermo Chemical Welding
(a): Thermit welding
(b): Atomic welding
6: Radiant Energy Welding
(a): Electric Beam Welding
(b): Laser Beam Welding
Welding Joints
Different types of welding joints are classified as Butt, Lap , Corner, Tee and edge joints which are shown in figure
