Atomic Hydrogen Welding

  Atomic Hydrogen Welding 

Introduction:

                       👉 Atomic Hydrogen Welding (AHW) is a combination of electric arc and gas Welding technique. It is a thermo-chemical arc welding process in which the workpiece are joined by heat obtained on passing a stream of hydrogen through an electric arc stuck between two tungsten electrodes.

Diagram:

working:

              👉 The equipment consist of a Welding torch with two tungsten electrodes inclined and adjusted to maintain a stable arc. Annular nozzles around the tungsten electrodes carry the Hydrogen gas supplied from gas cylinders.

              👉 AC power source is suitable as compared to DC because equal amount of heat will be available at both electrodes. A transformer with an open circuit voltage 300 V is required to strike and maintain the arc

             👉  The workpieces are cleaned to remove dirt, oxides and other impurities to obtain a sound weld. Hydrogen gas supply and Welding current are switched ON. An arc is struck by bringing two tungsten electrodes in contact with each other and instantaneously separated by a small distance of 1.5 mm. Therefore, the arc still remains between two electrodes.

             👉 As the jet of hydrogen gas is passed through the electric arc, it disassociate into atomic Hydrogen by absorbing large amount of heat supplied by the electric arc