Underwater welding is a type of commercial diving, which actually uses welding for underwater repair works and construction. Its uses include shipbuilding, offshore oil and gas, and while composing underwater infrastructure maintenance, underwater welding requires special training techniques and safety measures. In this blog, we will examine underwater welding, the methods used during underwater welding, and the roles of underwater welders in different industries.
What is Underwater Welding?
Underwater welding is the act of welding metal parts completely submerged in water, which is mainly oxygenated by oceans, lakes, or rivers. Special welding techniques and equipment are needed for welding underwater. Compared to normal welding, underwater welding is usually quite hard and demands more precision. Underwater welders should also understand underwater physics, wherein pressure, temperature, and visibility in the water influence welding.
What Do Underwater Welders Do?
The underwater welders include those working under the seas, oceans, or rivers, starting from ship and submarine repairs. These cover hulls, propellers, and all major parts of vessel repairs while needing to be done underwater rather than dry docked.
Oil Rig and Pipeline Maintenance
Underwater welders would include the ones who traveled offshore drilling platforms, as they do inspection, repairs, and reinforcement on underwater pipelines and structural components.
Bridge and Dam Maintenance
Repair corroded steel reinforcing bars in submerged portions of bridges and dams.
Salvage and Demolition
Underwater welders cut and remove metal sections to salvage sunken ships and to demolish old structures.
Underwater Construction
They weld together metal parts underwater to build underwater structures like docks, tunnels, and artificial reefs.
Underwater Welding Techniques
There are two basic underwater welding techniques: Wet welding and dry welding (also termed hyperbaric welding). Both have their uses.
1. Wet Welding
It is carried out directly underwater without an encapsulated area. Wet welding can be used for emergency repairs and temporary work. Major pros:
- Rapid deployment: for emergency work when there is no dry area
- Cost-effectiveness: No usage of costly hyperbaric chambers.
- Versatility: Can be done at different depths.
However, wet welding produces welds prone to hydrogen embrittlement and lower weld quality than dry welding.
2. Dry Welding (Hyperbaric Welding)
Welders in this process work under a pressurized dry weld chamber to join in a dry environment. The process applies to high-grade permanent welds. Advantages:
- More vigorous, long-lasting welds: With controlled atmosphere.
- Less risk of defects: No direct water exposure.
- Better visibility and accuracy: Easier to weld.
However, dry welding is labor-intensive and costly to install and can only be accomplished in unique environments.
Underwater Welding Challenges
Underwater welding is a dangerous profession and comes with many challenges:
Harsh Environment:
Welders swim in cold, dirty water with poor visibility and powerful currents.
Decompression Sickness:
It is also referred to as ‘the bends,’ when divers ascend too quickly, and there are nitrogen bubbles in the blood
Electrical Hazards:
Since water is an electrical conductor, there is a much greater risk of electrocution.
Structural Integrity Risks:
Wet welding typically results in weaker welds because of the rapid cooling and contamination from the water surrounding it.
Physical and Mental Stress:
Welders need to be physically fit and able to handle stress when working underwater.
The Future of Underwater Welding
Robotic welding and 3D scanning technology have made underwater welding safe and efficient. These technologies allow companies to employ 3D reverse engineering to create extremely accurate models of submerged structures so that welders can plan repairs much more accurately than they could otherwise have done. The lower risks raised via manual underwater welding are being raised to levels that lead to increased productivity.
Do you want to know more about underwater welding? Advanced 3D scanning & 3D reverse engineering technologies increase underwater welding efficiency. Contact Technosoft Engineering today to revolutionize the future of underwater welding!