Underwater welding combines the skill of welding with the challenge of commercial diving, requiring specialised tools to get the job done safely and effectively. Whether repairing pipelines, fixing ship hulls, or maintaining oil rigs, underwater welders rely on equipment that withstands high pressure, low visibility, and water exposure.

So, what equipment do you need for underwater welding? This guide covers everything from diving gear to welding tools, ensuring every welder is prepared for the job.

Essential Equipment for Underwater Welding

Underwater welders don’t just need standard welding gear—they require equipment designed to work in extreme underwater conditions. This includes diving suits, helmets, waterproof welding tools, and safety gear to keep them protected.

Diving Gear: Staying Safe Underwater

Before picking up a welding torch, underwater welders must have the right diving equipment to stay safe and comfortable while working beneath the surface.

1. Diving Helmets

A diving helmet provides breathing air, communication, and head protection. It shields the welder from debris, radiation, and pressure changes while allowing them to communicate with the surface team.

Types of diving helmets:

Open Circuit Helmets: Best for shallow dives, with direct airflow from the surface
Reclaim Helmets: Used for deep-sea welding, designed to recycle breathing gas for efficiency
Free-Flow Helmets: Ideal for high-contamination areas, providing a constant flow of fresh air

2. Diving Suits

A diving suit protects the welder from cold temperatures, sharp debris, and high water pressure. Most underwater welders wear dry suits made from neoprene, rubber, or shell materials, which provide thermal insulation and a watertight seal.

3. Gloves and Boots

Heavy-duty gloves: Flame-resistant and insulated to prevent burns and electric shock hazards
Waterproof boots: Protect against underwater sharp objects, heat, and electrical risks

Underwater Welding Tools

Underwater welders use specialised welding machines, waterproof electrodes, and protective gear to create strong and reliable welds underwater.

1. Underwater Welding Machine

How do you weld underwater? With a welding machine, the heart of the operation.

Underwater welders only use DC (direct current) machines, as AC (alternating current) is too dangerous underwater. These machines must be water-resistant, durable, and portable for different job sites.

2. Waterproof Electrodes

Underwater welders use waterproof-coated electrodes to maintain a strong arc and create a reliable weld. These electrodes are designed to:

Resist water damage
Provide a stable arc
Work in low visibility conditions

Choosing the right electrode type depends on the metal being welded and how deep the underwater welders are going.

3. Stinger (Electrode Holder)

A stinger is an electrode holder—designed to be lightweight, insulated, and easy to grip. Since underwater welding requires precision, a well-designed stinger reduces fatigue and allows for better control.

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Types of Underwater Welding and Their Equipment Needs

Different underwater welding types require specific tools and setups.

Wet Welding

In wet welding, the welder works fully submerged, using a DC-powered electrode that creates a protective gas bubble around the weld.

Key equipment for wet welding:
Waterproof stick welding (SMAW) electrodes
DC welding machine
Diving helmet with a welding visor

Since wet welding is performed in open water, it’s typically used for quick repairs or emergency fixes.

Dry Welding

Dry welding, or hyperbaric welding, is done inside a pressurised chamber that keeps the welding area dry.

Key equipment for dry welding:
Hyperbaric chamber (to create a dry welding space)
Gas-powered welding equipment
Sealed protective gear

Dry welding produces stronger, higher-quality welds but requires more setup and specific equipment.

Safety & Communication Equipment for Underwater Welding

Commercial diving and welding are some of the most dangerous jobs, so safety gear is essential. Welders need equipment to communicate with their team, prevent electric shock, and handle emergencies.

1. Umbilical Cable

An umbilical cable supplies oxygen, power, and communication between the diver and the surface. This lifeline keeps the welder connected at all times.

2. Bailout Gas Supply

A bailout gas tank is a backup air supply that keeps the welder breathing in case of an emergency.

3. Knife Switch

A knife switch is a safety device that instantly cuts power to the welding circuit if needed. This prevents electric shock hazards while welding in water.

4. Underwater Communication System

Since welders can’t talk underwater, they use audio communication devices to stay in contact with the surface team. In case of equipment failure, divers also rely on pre-set hand signals.

Do You Have the Right Equipment for Underwater Welding?

Having the right diving gear, welding tools, and safety equipment is essential for underwater welders to work efficiently and safely.

What equipment do you need for underwater welding? From diving helmets and dry suits to DC welding machines and safety cables, every piece of equipment plays a role in keeping welders safe and productive underwater.

Looking for professional underwater welding services? Work with experienced teams equipped with top-tier marine welding gear for safe and efficient repairs.

What Equipment Do You Need For Underwater Welding?