Safety and protection technology of arc welding

Safety and protection technology of arc welding

I. Safety and protection technologyWhen arc welding is performed, attention must be paid to safety and protection. Safety and protection technology mainly includes preventing electric shock, arc radiation, fire, explosion, and poisoning by toxic gas and smoke.

II. Preventing electric shockWhen arc welding, the voltage of the power grid, the output voltage of the welding machine, and the voltage of the portable lighting lamp will cause electric shock. Therefore, measures should be taken to prevent electric shock. Or zero connection. The insulation of the welding cable and welding clamp should be good. If damaged, they should be repaired in time. When arc welding, insulated shoes and welding gloves should be worn. When welding in boilers, pressure vessels, pipelines, and narrow and humid trenches, insulating pads should be used, and someone should be on guard outside. When using a portable lighting lamp, the voltage should not exceed the safe voltage of 36V, and should not exceed 12V when working at high altitude. When working at high altitude, if you are working within 5m of the high-voltage line or within 2.5m of the low-voltage line, the power must be turned off, and a warning sign should be hung on the switch, and someone should be on guard. In case of electric shock, the power supply should be cut off immediately and rescue should be carried out in time.

Ⅲ. Prevent arc radiation
The strong arc and ultraviolet rays of the welding arc are harmful to the eyes and skin. When welding with welding rods, you must use a mask with arc welding goggles, wear work clothes and welding gloves. When multiple people are welding, they should pay attention to avoid mutual influence. It is advisable to set up arc protection screens or take other measures to avoid cross-influence of arc radiation.
Isolate sparks. When the wind speed is above level 6, open-air welding and high-altitude operations cannot be carried out without taking effective safety measures. There should be fire-fighting facilities near the welding site. After the welding operation is completed, the switch should be turned off, and the site should be cleaned up in time to completely eliminate the fire.

Ⅳ. Prevent fire
Organic dust, wood, sawdust, cotton yarn, straw mat hay, oil, gasoline, paint and other flammable items should be thoroughly removed within 10m of the ignition source of the welding operation, below the high-altitude operation and within the range of the welding sparks. If there are flammable items that cannot be evacuated, such as wood, unremoved thermal insulation combustible materials, etc., reliable safety measures should be taken, such as spraying with water, covering with wet sacks, asbestos cloth, etc.

Ⅴ. Preventing explosions
There must be no explosive items within 10m of the welding operation point. Welding operations are strictly prohibited in oil depots, oil product rooms, acetylene stations, paint spray rooms and other rooms with explosive mixed gases. Without special measures, welding is not allowed on pressure vessels and pipelines with pressure inside. Before welding containers that have been filled with flammable and explosive items, the items contained must be completely drained, replaced with water, water vapor or nitrogen, and cleaned: the concentration of the gas medium must be tested and analyzed with instruments such as explosion meters; during welding operations, the cover must be opened and the operator must stay away from the container opening.

Ⅵ. Prevent poisoning from toxic gases and smoke
When welding with welding rods, toxic gases and dust such as soluble fluorine, hydrogen fluoride, manganese, and ammonia oxides are produced, which can cause fluorine poisoning, manganese poisoning, and welding pneumoconiosis, especially when welding with alkaline welding rods inside containers and pipes. Therefore, ventilation and smoke exhaust measures such as comprehensive ventilation, local ventilation, and small welding fume exhaust units should be adopted according to specific circumstances.