Safety Recommendations for Arc Welding

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The operator beginning his career in operating arc welding machines must go through and become familiar with these general safety recommendations to avoid accidents and injuries. Safety recommendations while working with arc welding process such as flux-cored arc-welding, shielded metal arc welding, submerged arc welding, gas tungsten arc welding, plasma arc welding, gas metal arc welding are given as under.

The body or the frame of the welding machine should be efficiently earthed. Pipe lines containing gases or inflammable liquids shall not be used for a ground return circuit. All the earth connections shall be mechanically strong and electrically adequate for the required current.
Arc welding machines should be properly grounded (earthed) as a safety measure to prevent people from accidentally coming in contact with electrical hazard.
Arc welding technician must use either helmet or a hand-shield fitted with a special filter glass to protect his/her eyes from infra-red and ultra-violet light which is emitted during arc welding process.
Excess ultra-violet light emitted during arc welding can cause an effect similar to sunburn on the skin of the welding operator(welder).
The welder’s body and clothing should be protected from radiation and burns caused by sparks and flying globules of molten metal with the help of gloves and apron. Gloves protect the hands of a welder. Apron made of leather or asbestos is very useful to protect welder’s clothes and his trunk and thighs while seated he is doing welding.
For overhead welding, protection for the head of welder is required. Leather skull-cap or peaked cap will protect head from sparks.
Leather jackets and lather leggings need to be used for body protection.
Welding equipment shall be inspected periodically and maintained in safe working order at all times.
Ensure that arc welding machines are of standard quality.
All parts of arc welding set shall be suitably enclosed and protected to meet the usual service conditions.
Operators need to protect themselves from welding rays, flying sparks, metal spatter, hot slag particles, hot stubs, fumes and gases when welding in confined spaces.
In alternating current (AC) arc welding machines, in transformers; the secondary circuit shall be thoroughly insulated from the primary circuit. Input terminal shall be completely enclosed and accessible only by the means of tools.
The primary side of the transformer shall be provided with suitable wire terminals inside the machine case.
Welding (secondary) terminals shall be so arranged that current carrying parts are not exposed to accidental contact.
In a transformer, the welding circuit should be made separate from power circuit, so that there is no risk of the operator suffering serious current shock or burns through power voltage appearing across the electric holder.
At or near each welding machine, a disconnecting switch shall be provided to turn off welding process in case of emergency.
Control apparatus provided with the welding machine shall enclose except for the operating wheels, levers, etc.
Winding’s of a transformer suctioned or compressed-air need to be cleaned periodically.
Before undertaking any maintenance work on welding machines disconnect them from the main electric power supply.
Other arc welding equipment’s, electrode holders should be soundly connected to the welding lead.
There should be of adequate rating for the maximum welding current to prevent them from heating up and be coming too hot to handle.
Operators holding electrodes need to hold shields to protect hands from heat of the arc. Installation of all metallic of current carrying parts, including the jaws which grip the electrodes, is recommended.
Hot electrode holders should not be dipped in water because the retained moisture may cause an electric shock.
Welding cables need to be completely insulated, flexible type. They should be capable of handling the maximum current required for the work to be in progress. If the cable insulation is damaged, do not operate the equipment. The welding cable should be free from repair or splices up to a minimum distance of three meters from the electrode holder.
Fully insulated cable connectors of capacity at-least equivalent to that of the cable shall be used to connect two cables together.
Welding cables need to be kept dry and free from the grease and oil to avoid premature breakdown of insulation.
Construction of arc welding machines should be such that they can operate satisfactorily even under conditions of saltish or moist air as in coastal areas, dust, smoke, excessive vibrations, fumes, steam, corrosive atmosphere, etc.
One should not work on the wiring of an arc welding machine unless qualified to do so.
Welding equipment operated in the open place shall be protected from the weather condition. If it is wetted; it need to be thoroughly dried before starting operation.
Ensure that proper terminals are used on the arc welding machines for the power line voltage connection.
Both the terminals of the welding generator should not be bonded to the frame of the welding machine.
Periodically clear out the accumulated dust on the welding machine with suction cleaner as this will not blow dust into other parts of the welding machine.
Don’t over grease; over greasing may foul the commutators of direct current (DC) generator.
Periodically clean commutators of DC generator using fine sand paper.
Excessive sparking may result in a worn commutator of DC generator which need to repaired by skimming in a lathe machine.
Brushes should move freely and have adequate spring tension. This can be tested by lifting and releasing them. Brushes should snap be firmly against the commutator of DC generator.
Periodically attention need to be taken for cleaning switch contacts.
Greasing points needs attention periodically.