THE PROCESS OF UNDERWATER / HYPERBARIC WELDING – MIXING ELECTRICITY WITH FLUID

Generally the combination of electricity and fluid are considered a really bad idea. There is an unpredictable reaction when electricity comes in contact with water since there is no specific path for the flow of electricity (unlike a copper wire). There is a definite science behind underwater welding. Underwater welding can be used in two forms dry and wet. Dry welding is also known as hyperbaric welding - applied through enclosures called habitats. This habitat is operated at a pressure set at about .007 pounds per sq. inch just above the outside atmospheric pressure. This causes a small bump in pressure up to the surface level providing a continuous volume of air for the welders in their working chambers. Air is pumped into the habitat from the either the ceilings or sidewalls by a team at the surface. The air fluctuation also avoids building up toxic fumes into the habitat. The underwater wet welding technique uses SMAW or shielded metal arc welding where the welder and the electrode are completely surrounded by water. For wet welding, the electrical cables are insulated twice and only current from the direct source is used instead of an alternating current. Gaseous bubbles are formed around the arc that protects all wet welds.