UNDERWATER WELDING


[41053]


INTRODUCTION


It is an important tool for underwater fabrication works.
Any repair method will require the use of under water welding.
Such as number of offshore structures including oil drilling rigs, pipe lines.



Wet welding:


It is directly expose to the wet environment.
It is open air welding.
Most effective efficient economical method.


Dry Welding:


This method produce high quality welded joints.
Gas tungsten arc welding use this process.
The area under the floor of the habitat is open to water.
The welding is done in the dry but at the hydrostatic pressure of the sea water surrounding the habitat.



ADVANTAGES


Speed of the operation is very high.
Equipments are very minimum.
The expenditure is very minimum.


DISADVANTAGES


Poor visibility
Weld is quenched is very fast in under water.
It decreases impact strength and ductility
Hydrogen Embrittlement
Amount of voltage very limited