Safety Recommendations for ARC Welding
The newcomer in the field of arc welding should read through and get familiar with the following general safety precautions.
1. The welding machine’s body or frame must be effectively earthed. Ground return circuits must not be used in pipe lines carrying gases or dangerous liquids, or conduits carrying electrical conductors.
All earth connections must be sturdy mechanically and electrically to handle the appropriate current.
2. Because the welding arc emits both infrared and ultraviolet light, the operator must wear either a helmet or a hand-shield with a particular filter glass to protect his or her eyes.
3. Excess ultra-violet light might induce a sunburn-like effect on the welder’s skin.
4. With the help of the following, the welder’s body and clothing are protected from radiation and burns caused by sparks and flying globules of molten metal:
5. A welder’s hands are protected by gloves.
6. A leather or asbestos apron is highly important for protecting the welder’s clothes, as well as his trunk and thighs, while seated.
7. When welding overhead, some type of head protection is essential.
8. A leather skull cap or a peaked cap will suffice.
9. Body protection is also available in the form of leather jackets and leather leggings.
10. Welding equipment must be inspected on a regular basis and kept in good operating order at all times.
11. High-quality arc welding machines are required.
12. To meet the standard service requirements, all parts of the welding set must be properly encased and protected.
13. While welding in confined areas, such as a rail tank waggon, welders and workers must be protected from welding rays, f1ying sparks, metal globules and metal spatter, hot slag particles, hot stubs, fumes and gases, and falling when welding at a height from the ground.
14. The secondary circuit in AC arc welding machines and transformers must be completely isolated from the primary circuit. The input terminal must be entirely enclosed and only accessible with tools.
15. Inside the machine casing, the primary side of the transformer must be equipped with adequate wire connectors.
16. Welding (secondary) terminals must be set in such a way that current-carrying portions are not accidentally contacted.
17. In a transformer, the welding circuit should be kept separate from the power circuit to avoid major shock or burns to the welder if power voltage appears across the electric holder.
18. A disconnecting switch must be provided at or near each welding equipment.
Except for the operating wheels, levers, and other controls, the welding machine’s control apparatus must be enclosed.
20. Transformer windings should be vacuumed or compressed-air cleaned on a regular basis.
21. Disconnect the welding machine from the main supply before performing any repair.
Electrode holders should be securely linked to the welding lead in other arc welding equipment.
23. They should be rated for the maximum welding current to avoid overheating and becoming dangerously hot to handle.
24. Discs or shields should be provided with the electrode holder to protect the welder’s hands from the arc’s heat. It is advised that all metallic current carrying elements, including the jaws that grab the electrodes, be installed.
25. It is not permissible to dip hot electrode holders in water because the remaining moisture may create an electric shock.
26. Welding cables must be completely insulated and flexible. If the cable insulation is damaged, do not operate the equipment. They should be capable of managing the maximum current needs of the job in progress, taking into consideration the duty cycle under which the welder is working.
27. Up to a distance of three metres from the electrode holder, the welding cable should be free of repairs or splices.
28. To connect two cables together, fully insulated cable connectors with a capacity at least equal to that of the cable must be used.
29. To minimise premature insulation breakdown, welding cables must be kept dry and free of grease and oil.
30. Welding devices that use arcs should be properly grounded (earthed).
31. Arc welding machines should be built in such a way that they can function well even in the presence of salty or wet air, such as that found in coastal areas, dust, smoke, fumes, and gases, extreme shock or vibrations, steam, and corrosive atmosphere, among other things.
32. Working on the wiring of an arc welding equipment should only be done by those who are qualified to do so.
33. Welding equipment that is operated outside and exposed to the elements must be weatherproofed. If it has been wetted, it must be completely dried before usage.
For the power line voltage connection, proper terminals should be used on arc welding machines.
35. Neither terminal of the welding generator shall be bonded to the frame of the welding machine.
36. Periodically clear out the accumulated dust from the welding machine with suction cleaner as this will not blow dust into other parts of the machine.
37. Excessive grease might clog the commutators in a DC generator.
38. Using fine sand paper, check and clean the commutators of the DC generator on a regular basis.
Excessive sparking can cause a worn commutator in a DC generator, which can be repaired by skimming in a lathe.
Brushes should be able to move freely and have sufficient spring tension. Lifting and releasing them can be used to test this. Brushes should be snapped securely against the DC generator’s commutator.
41. Greasing spots require treatment on a regular basis.
Switch contacts should be cleaned on a regular basis.
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