Underwater welding—a complex and dangerous endeavor that brings with it a great sense of accomplishment upon completion— is a relatively unknown and often misunderstood form of welding. As its name suggests, underwater welding involves welding while submerged beneath the surface of water.
This form of welding is regularly employed in the repair and maintenance of offshore structures and vessels. According to the United States Bureau of Labor Statistics, there were around 5,670 employed underwater welders in 2019, who earned a median hourly wage of $22
In addition to having a good knowledge of different welding techniques, an underwater welder should possess a unique skillset to be able to adapt to the ever-changing conditions of underwater welding. With this article, we will take an in-depth look at underwater welding—its unique history, the many risks involved, and how to choose the right equipment to get the job done. Read on to learn all about underwater welding!
What is Underwater Welding?Underwater welding is a specialized form of welding which is performed in a body of water. It is used in a wide range of applications such as offshore oil rigs, construction of ships, joining and repairing pipelines, and on many kinds of marine vessels.
It is a challenging and dangerous form of welding, as the welders are submerged in water and have to protect themselves and the equipment from the pressure of the ocean.
How is Underwater Welding Done?
Underwater welding is mainly done using wet welding techniques. Wet welding techniques involve the use of a water-cooled electrode, which is connected to a high current-voltage source.
The electrode conducts the current through the water to the metal which is being welded. This creates an electric arc, which produces the heat and pressure needed to join the metals. All of the welding is done either inside a chamber which is sealed from water and pressure or on the outside with a water filled jacket.
What is the History of Underwater Welding?Underwater welding gained traction in the 1940s, when it was used to repair damaged warships and submarines.
Initially, welding was done with electrodes filled with combustible material which could stay lit for a few minutes, enabling the welding process to be carried out. Later, the use of inert gas filled electrodes was developed. These enabled welders to work for longer periods of time and make stronger and more durable welds.
What are the Different Types of Underwater Welding?There are three main types of underwater welding: dry welding, wet welding and hot water welding.
- Dry welding: Dry welding is the type most commonly used when welding underwater. It involves the use of an inert gas to form an oxygen-free environment around the weld area, allowing welders to carry out the welding process without any water present.
- Wet welding: Wet welding involves a body of water, or a water-filled chamber, to fill the welding area and provide cooling for the weld. This type of welding is mainly used for deep sea welding.
- Hot water welding: Hot water welding uses hot water as the cooling medium for the weld. It can be used for welding in shallow waters, up to about 20-30 feet in depth.
What are the Advantages and Disadvantages of Underwater Welding?Underwater welding has its advantages and disadvantages, like any other type of welding. Here are some of the pros and cons:
- Advantages: Underwater welding can produce a strong and durable weld due to the pressure of the water, it can be carried out at depths which are not possible with dry welding, and it is often faster and more cost-effective than other welding methods.
- Disadvantages: Underwater welding is a very challenging and dangerous job, as welders are exposed to the pressure, cold and darkness of the ocean. It also requires very specialized and expensive, expert-operated equipment, and it can be difficult to create a bead that is uniform and aesthetically pleasing.