Underwater welding is increasingly used as a temporary or permanent repair technique in, for example, ship’s hull repair, welding anodes, welding cracks in steel, applying reinforcements, etc.
Underwater welding is more complicated than dry welding. Sufficient underwater visibility is a requirement. The diver must be able to secure himself well. Because the weld cools down faster, a different technique than above water is used. Nevertheless, very good welds can be laid down.
What is needed and what are the conditions to carry out a welding job properly:
First of all, a diving company that:
- Has sufficient experience to prepare the work;
- Has experienced welders;
- The work yields with a good inspection and reporting.
The following variables play a role:
- Water flow;
- Underwater view;
- Water depth;
- Salt or fresh water;
- Experience of the welder;
- Steel grade;
- Welding position.
Good preparation is important. The action plan contains at least the following:
- What will the welding connection look like;
- Not every welded joint is suitable for underwater use;
- How is the access for the diver;
- Avoid overhead welding as much as possible;
- What type of electrode to use;
- What welding procedures;
- The selected welders for the work.
Wet welding is used for both temporary and permanent welding joints. Temporary welds are used as emergency repairs, for example in case of ship damage (collision, grounding). Examples of both temporary and permanent welding:
- Reinforcement plates;
- Dense welding of cracks in steel;
- Repairing damage to sheet piling;
- Ship repairs to rudder, rope quard or shell plating;
- Conductor frames;
- And much more.