Safety measures for underwater welding square tube

Underwater welding square tube, the equipment and power supply used should have good insulation and waterproof performance, its insulation resistance value shall not be less than 1MΩ, and should have anti-salt spray corrosion, atmospheric corrosion and seawater corrosion resistance.

Underwater wet welding and cutting, the circuit should be installed in the welding special automatic switch box. Underwater dry or local dry welding, the circuit control system should be installed in the accident alarm system and power-off system.

Electrodes shall be thoroughly insulated and waterproofed to ensure that electrical contact occurs only at the point where the arc is formed.

When diving for square tube welding operation, special protective clothing and special gloves must be worn.

Underwater arc just formed, the surrounding water will evaporate to produce a cavity or bubble. Due to the cooling and pressure of the water, the voltage required to induce the arc underwater is higher than on land. From the point of view of operational safety, underwater welding power supply must use direct current, prohibit the use of alternating current. Its no-load voltage is generally between 50-80V.

Diving welders who directly contact with the control of electrical appliances must use isolation transformer, and overload protection, welding machine must be grounded, grounding wire head should be polished to prevent corrosion.

In the process of welding or cutting square tube, often need to replace the welding rod. In the underwater replacement of welding rod, must first issue a pull signal, confirm that the circuit has been cut off, before removing the head of the welding rod, and then replace the welding rod. Otherwise, it is easy to cause electric shock and danger.

In the underwater welding of square tube, diving welders should not back to the grounding point, that is, they are placed between the work point and the grounding point. Otherwise, it is not only easy to produce electric shock accident, but also easy to make the metal parts of diving equipment by electrolytic corrosion. Care should be taken not to place the hand on the workpiece to be welded and cut, and at the same time touch the welding rod or welding handle to the helmet and receive electric shock.