High temperature flame is used to melt the metal surfaces. This high temperature flame is obtained by the mixture of two gases. These gases are stored in two different cylinders i.e. Oxygen in black cylinder and Acetylene in maroon cylinder. The quantity of either gas can be regulated by regulators on the torch. The metals to be weld are placed together and melted by heat from the flame. A filler material is also used to complete the weld.
Types of flames:
The different forms of flames are
Neutral flame: It is obtained by mixing equal quantities of Acetylene and Oxygen. It is used for welding of ferrous metals.
Carburizing flame: It has more quantity of Acetylene and less quantity of Oxygen.
Oxidizing flame: It is obtained by excessive amount of Oxygen. It has very high temperature so it is used for cutting operations. It is used for welding of non-ferrous metals like Brass and Bronze.
Equipments used in Gas welding:
· Welding torch
· Safety screen (or goggles)
· Pressure regulator
· Oxygen and Acetylene cylinders
· Gloves
· Welding rod
· Flux
· Apron
· Spark lighter