Underwater welding is a process that is primarily used to make repairs on ships, pipelines and offshore oil platforms. Welding techniques are hazardous when performed on dry land, adding water only increases the amount of risk the welder experiences every time they dive. There are two areas of underwater welding, wet and dry. Both are included in the hyperbaric welding category which includes welding that is done at increased pressure, such as welds that are performed underwater.
Dry underwater welding is performed by placing a structure around the area to be welded. The structure is then sealed around the weld area and gas is used to fill the area created. The welding is then performed inside this chamber. Dry underwater welding is considered to be a very accurate welding technique. Dry underwater welding exposes the welder to high levels of pressure like those that are experienced when diving in deep waters. Although dry underwater welding is performed in a gas filled chamber, there are still risks involved. All underwater welders, whether it is dry or wet, need to be skilled in the operation of the specialized equipment that is involved in this type of welding.
Wet underwater welding uses waterproof electrodes to supply power to the welding tools. Wet underwater welding is considered by many to be easier to initiate because there is not the need to construct a chamber in order to conduct the welding. Wet welding also allows the welder to move more freely than being enclosed in the chamber. Wet underwater welding presents more risks to the welder than dry underwater welding; one of the primary risks that a wet underwater welder is exposed to is electrocution. The equipment used in wet underwater welding needs to insulated and the electricity levels must be properly maintained at all times. Other risks of wet underwater welding include any problems that are associated with diving. Not only do underwater welders need to be experienced in welding techniques, they must also be certified divers as well. Wet underwater divers can experience a build-up of oxygen and hydrogen gases which can be explosive.
Welding presents many different risks to welders, underwater welding both wet and dry present even more. Underwater welding is not something that should be attempted by anyone without any diving experience. Because of the specialized equipment and techniques used, all underwater divers must be certified in both welding and diving.
