In this Article, We Explain How does underwater welding works, and What is Underwater welding with History, and the Salary of Hyperbaric welding.
Underwater welding sounds like some extraordinary things, but at the same time, it is extremely important. Being a layman, who has never dived into the deep seas and rivers, would only consider the underwater welding as a dream able thing.
Why will somebody have to perform underwater welding? You must have seen or heard in the news that there are some wires near the seabed, and the companies are trying to fix those infrastructures, these are the points where we need underwater welding.
What is underwater welding?
The name of the term underwater welding says it all; it is the welding process exclusively done under the waters; it can be oceans, seas, or rivers.
Underwater welding is generally referred to as hyperbaric welding. It started in 1930 when the world was changing in the wake of globalization. Unlike the on land, underwater welding is a different task, and only expert welders who are some amazing divers can do this.
Underwater welding is not a cheap process; usually, big companies and industries hire people for underwater welding. It is a tricky affair with a high risk of safety. Underwater welders charge a lot of money for these tasks.
The riskiest thing in underwater welding is the mixing of electricity and water, which is indeed a dangerous thing. But with the help of technology and new inventions, scientists and engineers have now made some special equipment and suits for safe underwater welding.
History of underwater welding
The underwater welding was an invention by a Soviet engineer Konstantin Khrenov in 1932; US engineers and scientists took up this concept of welding metal underwater.
During the world war, two underwater weldings made its way to the US navy. Cyril Jensen started an underwater welding program to teach your navy officers and technicians for the checking and better conditioning of the navy submarines and ships.
Types of underwater welding
Two types of underwater welding are commonly exploited throughout the world; with the passage of time, engineers are trying to figure out new ways for underwater welding, here we will only discuss these two types of underwater welding
This type of underwater welding is a bit expensive as it requires a dry chamber, filled with the hyperbaric gas, instead of water. The welders are supposed to sit in that chamber for doing this welding job.
These gasses are a mixture of helium and oxygen; it means that the chamber’s environment is not suitable for open breathing. The welders are supposed to wear masks and carry oxygen tanks with them.
Before welding, the chamber is prepared with great care, and the conditioning of the chamber is a very interesting task. First, they flush out all the water from the chamber and the infrastructure; then, to maintain the chamber’s pressure, the technicians will balance the air pressure in the chamber.
The dry chamber welding is further divided into four types. The welders pick up the most suitable type of dry welding, and this selection depends upon the size of the chamber and the infrastructure to be welded.
- Pressure welding is for the welding of a pressure vessel at a maintained atmospheric pressure of sea level.
- Habitat welding is also like the pressure welding, but here, the chamber’s pressure is similar and equal to the pressure outside the chamber.
- Dry chamber welding is also an interesting type of dry welding, where the welders are supposed to stand beneath the chamber, and they will only be partially submerged in the chamber while wearing the diving gear.
- Dry spot welding, in this technique, the chamber is only as small as the person’s head, and the divers use a simple electrode for his type of dry welding.
The wet welding is also known as shielding metal arc welding; here, the welders are supposed to go down in the water and then repair or weld the infrastructure. They go down with some reliable signaling devices.
Upon reaching the target infrastructure, they ask their team to turn on the electricity. You must be wondering about the range of electricity; it is no more than 400Amp for a regular weld.
Unlike the regular welding, we do not use the AC for the underwater wet welding, but DC is considered the most suitable type of current for this purpose.
The electrode used for the wet underwater welding is already coated, which cuts down the risk of electrocution, and keeps the diver welders safe.
Like dry welding, wet welding is further classified into other types; the two common types of wet welding are the following.
- The Flux-cored Arc welding is the welding with material flux, and the metal to be fed in is already present in the electrodes.
- The friction welding, it is a unique type of wet underwater welding, where the frictional technique is used to melt the metal.
- Gas tungsten arc welding, in this type of welding, we use a non-consumable welding electrode. This electrode is made up of tungsten; that is why the metal’s name refers to this technique.
- Gas metal arc welding, here the welders need to be very conscious about the metal to be fed. The welder is supposed to use the shielding gas through the welding gun to weld the metals together.
- Plasma arc welding: this method is suitable for welding stainless steel, aluminum, and a few other metals. The welders use the electric arc in such a manner that the regular arc will produce a high arc and intensified heat, which will ultimately weld the metal.
Procedure for underwater welding
Underwater welding is a long procedure, and expecting a simple welding task here would not be fair.
1. Preparing a chamber
This step will vary when you are doing underwater welding for some companies; you can ask the company to build a chamber depending upon the metal and its designs.
2. Hold a meeting
Before you and your team members must start the work, it is essential to hold a meeting; in this particular meeting, you will discuss the pros and cons of the type of welding you must opt for the specific project.
3. Get the DC welding generators.
You cannot use the AC generators here because they will increase the risk of electric shocks in the wet welding process; even for the dry welding, the DC welding generators are preferable. If in case you do not have a DC generator, then you must borrow one. Otherwise, you cannot conduct an underwater welding process at all.
4. Get the gloves
You need insulated gloves, and they are not made up of the regular material but hard plastic, which can never let the current pass through it. In the case of wet welding, you must try to wear long and thick gloves.
5. The ground lead arrangement
For a safe process, you must keep the ground lead close to the worksite. This way, the diver will be aware of the electrode and the ground. It is merely for the safety of the divers.
6. The disconnect switches
In regular welding generators and machines, the positive disconnect switch is usually at the main generator and not at the welding torch side. In wet welding, it should be present at the divers’ end so that they may be able to disconnect and break the circuit immediately in case of any inconvenience.
7. The positioning of the articles
To keep the article in the position, you can only use the C-type clamps should be used for the sake of grounding the article. Moreover, the belts and holders used for keeping the article in place must have the required elasticity and slack.
The divers must check the slack of the rods or whatever which will hold the article before diving in. this is to check the strength and the pull-off chance of the article. The buoyant forces can be disturbing during the wet underwater welding, so holding the article in place is essential.
8. The testing
The test weld is important to check the welding heat in water; this way, the team can understand the required range of current and metal feeding speed.
9. Switch of the electrodes
While welding, you must turn off the electrodes once it is consumed by three inches. It is to ensure the weld quality will make the process a bit longer, but in the end, it is the safest way to weld. Whenever the electrode is three inches consumed, the welders must signal the team to switch off the torch.
Advantages of underwater welding
You must be wondering why we must learn underwater welding when we can easily take out the article and weld it. I had the same opinion until I researched and found out some advantages of underwater welding.
- The underwater welding, especially the dry welding, is relatively safe, and the welders are not supposed to stay in the water while welding two metals together.
- Wet welding is an affordable procedure.
- It is not a long process, especially when the team has decided to do wet welding because the welders are not supposed to stay longer.
- In dry welding, the H2 levels are quite low, and the water level is equal to zero. Thus the welding results are quite great.
- A better understanding of the surface because the team members would study the surfaces through underwater equipment such as cameras.
- The tools and equipment used for both dry and wet underwater welding are robust and reliable.
Disadvantages of underwater welding
- The arrangement of the equipment and the making of the dry chamber can be tough.
- The cost of the habitat building varies, and it depends upon the depth of the sea.
- In wet welding, welders confront poor visibility, which can be a risky affair.
Frequently asked questions about underwater welding.
This section deals with the most common and frequently asked questions regarding underwater welding.
a) Is underwater welding dangerous?
The combination of water and electricity is not a desirable thing. It is one of the scariest things one can ever imagine. However, if you are a skilled person and the team comprises sensible people, it is a safe experience with a lot of adventure.
The only thing one must be worried about the reliability of the equipment and some backups. In many cases, the welders came out safe only because they had some alternative to keep them safe.
The most common threats of underwater welding are hyperthermia, decompression sickness, and drowning. You need to be a great swimmer to become an underwater welder. Without proper training, one must not opt for underwater welding at all.
b) What is the salary of an underwater welder?
The salary of an underwater welder is $55000 annually. It is because the job is very risky, and the divers are extremely talented. It is the average salary, some welders are earning more than this, as they are apt in working in deep oceans, and of course, because of their experience.
Underwater welding is one of the strangest things we can imagine, but welders seeking a career in the welding world must have thought of it. It is not s impel affair, and only hard work and determination can take a regular layman to this level.
The underwater welding is worth it if you are an adventure-loving person who is not afraid of unusual circumstances. Even though science and technology have paved the path, there are still many underwater welding risks.
Your luck is the only thing that can save you in underwater welding; as a matter of fact, one can never understand what is happing under the water.