Underwater welding is done under water in the ocean and is used when there is a need to repair a ship, oil platforms that are offshore and pipelines. Usually these all need to be repaired using steel only. There are two basic types of underwater welding and these will depend on whether the situation needs a dry welding or a wet welding. These are called hyperbaric welding.
Both of these occur underwater but the dry aspect is done through a special pressure chamber that creates the dry environment. This dry mode can be better controlled underwater. This is used when there is a need for very deep water welds and where a high degree of strength is required. Research is being conducted to see whether dry welding can be done at depths of 1000 meters. When dry welding is used, the chamber is filled with a gas mixture has to be used to seal the structure that is being welded. Usually a gas tungsten arc welding is used to make sure that this is a strong weld. For those structures that receive wet underwater welding it is difficult to know whether the weld has worked because the risk that may be involved are difficult to see in the water.
One of the challenges with doing welds underwater is that integrity of these welds are difficult to determine because there can be defects that are underneath the surface that is being weld and these can be hard to find. There are several processes that can be used underwater and these include flex core arc welding, friction welding and shielded metal arc welding. All of these are good to use underwater with a waterproof electrode. Since hydrogen will cause cracks in metal, low carbon steel is usually used in performing the underwater welding.
The greatest challenge for underwater welding is that is may not be a very safe situation because the welder is in water. This means that there is a higher risk for electric shock and some equipment being used may not be adaptable to a marine setting. Any type of welding equipment that is going to be used underwater has to be adapted to this environment and it needs to be insulated and have a controlled welding current.
Another area where welders who work underwater will need to be careful about is that they are susceptible to decompression sickness if they have been underwater for a long period of time. They will be breathing an increased pressure of gases during this the time they are welding and this can create problems for them when they come out of the water. Both hydrogen and oxygen will also build pockets underwater because of their ability to explode. Some divers have found that they experience a metallic taste in their mouth, especially when they fillings that are made of amalgam. There may also be problems with cognitive processing or musculoskeletal issues when a diver has been exposed to underwater welding over time.
Both of these occur underwater but the dry aspect is done through a special pressure chamber that creates the dry environment. This dry mode can be better controlled underwater. This is used when there is a need for very deep water welds and where a high degree of strength is required. Research is being conducted to see whether dry welding can be done at depths of 1000 meters. When dry welding is used, the chamber is filled with a gas mixture has to be used to seal the structure that is being welded. Usually a gas tungsten arc welding is used to make sure that this is a strong weld. For those structures that receive wet underwater welding it is difficult to know whether the weld has worked because the risk that may be involved are difficult to see in the water.
One of the challenges with doing welds underwater is that integrity of these welds are difficult to determine because there can be defects that are underneath the surface that is being weld and these can be hard to find. There are several processes that can be used underwater and these include flex core arc welding, friction welding and shielded metal arc welding. All of these are good to use underwater with a waterproof electrode. Since hydrogen will cause cracks in metal, low carbon steel is usually used in performing the underwater welding.
The greatest challenge for underwater welding is that is may not be a very safe situation because the welder is in water. This means that there is a higher risk for electric shock and some equipment being used may not be adaptable to a marine setting. Any type of welding equipment that is going to be used underwater has to be adapted to this environment and it needs to be insulated and have a controlled welding current.
Another area where welders who work underwater will need to be careful about is that they are susceptible to decompression sickness if they have been underwater for a long period of time. They will be breathing an increased pressure of gases during this the time they are welding and this can create problems for them when they come out of the water. Both hydrogen and oxygen will also build pockets underwater because of their ability to explode. Some divers have found that they experience a metallic taste in their mouth, especially when they fillings that are made of amalgam. There may also be problems with cognitive processing or musculoskeletal issues when a diver has been exposed to underwater welding over time.
