In 1932, a Soviet engineer, Konstantin Konstantinovich Khrenov invented underwater welding technique, and it was widely applied by the Soviet Navy at the time of World War II.
Underwater welding is a technique that is employed in various marine engineering projects, wherein welding is carried out under the surface of the water. Underwater welding is generally performed on steel, and needs special diving skills on the part of the welder.
The functions of an underwater welder include repairing pipelines, offshore oil platforms, ships, and other structures, which are submerged under the water.
Considering that taking the entire structures out of water in order to repair them, is not only a herculean task, but also a very expensive one, it seems rather advisable to work on such structures, keeping them in situ.
Underwater welding reduces the cost of the company by directly mending the damages under the water, thus saving time and a lot of money. The repairing is done by specialized welders, trained for the job.
Underwater welding can be divided into two main types - dry welding and wet welding. Both these, come under the category of 'hyperbaric welding, a high pressure welding method.
In dry underwater welding, the area which is supposed to be mended is enclosed in a chamber and the water is completely pumped out from that area.
The underwater welder, then, performs his repairing work inside this specially prepared chamber, which is totally dry even though it is under the water. Wet welding, on the other hand, takes place in a setting which is completely wet.
Dangers of Underwater Welding
A whole lot of regulations have been framed, so as to ensure that the underwater welder can be as safe as possible in the aquatic environment.
Nevertheless, no set of regulations can be foolproof, especially when a person goes underneath the surface of the water, and works with electric equipment. Following are some of the risk factors involved in the process of underwater welding:
Danger of an Electric Shock
The underwater welders, as we know, dive into the water in order to do their job. In spite of all the safety precautions that they may take, they are still quite exposed to the risk of getting an electric shock inside the water.
This might happen, especially when the welding equipment that is used is not adapted to work under the water. It is therefore advisable to get the equipment tested properly, and also to confirm that it is well-insulated and that a waterproof electrode is connected to it.
This will minimize, if not completely nullify, the risk of underwater electrocution. It is also necessary to switch off the electric current immediately after the work is done.
Possibility of an Explosion
Underwater explosion is another major risk that the underwater welders may have to face. The chances of such explosions are more in processes, wherein both, hydrogen and oxygen are involved, and may lead to the formation of numerous gas pockets.
Especially, within the enclosed chamber, during dry hyperbaric welding, the formation and combination of hydrogen and oxygen pockets is dangerous because they are explosive, when ignited. This underwater explosion can be extremely lethal.
Decompression sickness, also known as 'diver's disease', is a condition, wherein a diver (underwater welder in this case) happens to inhale certain harmful gases such as nitrogen, when he dives quickly from a high pressure zone to a low pressure zone.
If the welder dives too fast to the surface of the water, the possibility of nitrogen bubbles entering his bloodstream is immense. These bubbles, then spread inside the diver's body, and start showing numerous adverse symptoms.
Decompression sickness may lead variably to rashes, joint pain, paralysis or even death of a person. Decompression chambers and extra divers are provided to the welders as precautions for this kind of danger.
Breakdown of Dental Amalgam
Underwater welders often complain regarding a sort of a metallic taste in their mouth, which seems to be the result of the breakdown of their dental amalgam.
Recent studies have shown that in the process of electric welding and cutting under the water, a magnetic field with alternating current gets created. This magnetic field, in turn, induces a secondary current in the oral tissues of the welders, due to which their dental amalgam breaks down.
Musculoskeletal Issues and Hearing Impairment
The underwater welders are prone to certain problems pertaining to their musculoskeletal system, in the long run. Complaints may range from joint pain and muscle stiffness to back or neck pain.
Added to this, it has been reported that many of the underwater welders suffer from various kinds of hearing impairments ranging from temporary hearing loss to a permanent one.
Several underwater welders also complain of an impairment of their cognitive functions. These include problems such as partial loss of memory, lack of the ability of verbal reasoning, etc.
In some cases, sudden occurrence of clinical personality change has also been witnessed. Some of the cognitive problems in underwater welders occur also due to the decompression sickness that they might be suffering from.
- Underwater welders may sometimes, face hazards of drowning due to equipment failure.
- They may also suffer from lung, ear or nose damage, because of the high pressure that is exerted underneath the water.
- Dangers that are posed by the marine animals, cannot be ignored.
The underwater welders are, however, constantly in contact with their team members who are on the surface, in case they need any help. Immediate assistance is provided, in cases of risks. The underwater welders are also provided with sufficient air supply from the standard scuba breathing apparatus.
Underwater welding can be a promising career for people, who love adventure and going to virtually inaccessible places. However, proper and adequate training is required in order to ensure the safety of the welder, and also to make sure that nothing goes wrong while the work is in progress and even after it is done.