Underwater Welding Types & Projects
There are two forms of underwater welding. The one that is the most intriguing to everyone is underwater wet welding. This process is performed using a “stick” electrode that is especially prepared for welding in the water with no protection from the water.
The process is wet SMAW and is covered in the AWS D3.6 code book.
The second type of underwater welding is hyperbaric welding. It is performed in the dry in an underwater habitat or welding chamber.
It is a lot more involved and requires more fabrication as well as additional divers’ support equipment. Dry hyperbaric welds offer the same quality and mechanical properties as welds performed in a fab shop on land. Dry hyperbaric welds are also covered in the D3.6 code book and can be qualified as AWS D1.1, API 1104, B31-3 or any other topside welding code with the additional requirements of D3.6.
In a dry hyperbaric chamber, the diver-welder removes his dive equipment and dresses out in a breathing mask and welding hood. Then he or she performs all welding in a dry environment using any welding process like SMAW, TIG, GTAW or wire feed equipment. For safety reasons all underwater welding processes should be direct current.
Underwater Welders: Training & Skill
Throughout the world – including the military – there are probably less than 1,000 welder-divers who are qualified to perform all aspects of underwater welding.
The training and experience required to be a competent underwater welder takes years to develop and perfect. From a training aspect, it is easier to take a qualified topside welder and train him to dive than to take a diver with no welding experience and teach him how to weld.
The best welder-divers in the world come into the underwater welding field with 3-10 years of topside welding experience. Because dive crews are normally very small, it is also important to have experience in pipe fitting, plate fitting and fabrication.
Q&A: Oxylance’s Products & Company History
As someone who’s highly trained in underwater welding, have you personally tested some of Oxylance’s electrodes? What types of tanks/facilities does Oxylance have on hand to do so?
I worked in research and development at Chicago Bridge and Iron (CB&I) in their underwater welding department.
The electrodes that we sell today are electrodes that I personally developed after I left CB&I. I set the world’s record for the deepest wet weld ever qualified to D3.6 at 326 feet with the same electrodes we sell today. So yes – I have extensive experience with the rods we manufacture and sell.
We do not have a test facility here. We use facilities at various diving companies to test the electrodes now, so we have third party verification of the electrodes’ capability.
Since its start in 1974, Oxylance has been known for its production of quality burning bars. How has the manufacturing process for these changed over the years?
The manufacturing process hasn’t changed for burning bars and lance pipe in 40 years. We have just refined the manufacturing equipment to give us the ability to manufacture products faster and more efficiently.
Safety training is highly valued at Oxylance. What’s an example of a training exercise that employees undergo to ensure they’re following correct procedures?
We do not have safety training for our employees in the manufacturing side. We do train them in the manufacturing process. Our safety training is designed for the people in the field who are using our products. For that, we have various training scenarios depending on the product and the job being performed.
For example, we have training for people doing demolition, and then we have different training for people using our lance pipe in steel mills.
Can you explain the basic differences between tubular steel and exothermic cutting rods? What’s the difference in application?
Tubular Steel cutting rods (Aqualance): Burn hotter and can cut thicker material underwater. Depending on the amperage used (minimum 300, maximum 400) the arc temperature can be as low as 12,000 °F at 300 amps, and up to 18,000 °F at 400 amps.
Exothermic means that the rod will burn without power. You start the rod burning with an arc and a flow of oxygen. When you turn the power off and leave the oxygen flowing, the rod will continue to burn until it is burned up or you turn the oxygen off. The tip temperature of the exothermic reaction is about 7,400 °F.
Two big differences: Tubular steel has much higher tip temperature and the exothermic rod is consuming whether the diver is cutting steel or just sitting there watching it burn. The tubular steel rod only consumes when it is actually arcing and burning.
What’s one of the major highlights of working in the industry?
Constantly meeting new people and coming up with ways to help people accomplish difficult jobs.
– Greg Cain, Vice President of Technical Services at Oxylance Inc.
Manufacturing since the mid-seventies, Oxylance Inc. specializes in cutting and welding equipment (including underwater) for fabrication industries across the world. Their products are continuously tested and refined for quality and safety assurance.