Welding, Soldering, Brazing

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Welding, Soldering, Brazing

• Max Akhterov
• Zettl Group Safety Talk
• 11/07/06

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Welding

• Welding is a materials joining process
  which produces coalescence of materials by
  heating them to suitable temperatures with or
  without the application of pressure or by the
  application of pressure alone, and with or
  without the use of filler material.
• 
  
  The American Welding Society

• AWS distinguishes the welding processes according
  to
• Mode of energy transfer
• Influence of capillary attraction in effecting
  distribution of filler metal in the joint

• Groups of welding processes
• Arc welding
• Brazing
• Oxyfuel Gas Welding
• Resistance Welding
• Solid State Welding
• Soldering
• Other

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Hazards
1. Fumes and Gases
2. Electric Shock
3. Radiation
4. Noise
5. Fire and Burns
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Fumes and Gases

• Fumes are solid particles which originate
  from welding consumables, the base
• metal, and any coatings present on the base
  metal.

• Possible effects of over-exposure (magnesium,
  copper, zinc, lead, chromium, etc.)
• Irritation of eyes, skin, respiratory system
• Symptoms nausea, headaches, dizziness, metal
  fume fever
• manganese overexposure can affect the central
  nervous system
• resulting in impaired speech and movement
• In confined spaces the gases might displace
  breathing air and cause asphyxiation
• How to avoid
• Do not breathe the fumes
• Use respiratory protection
• Use enough ventilation or exhaust
• Be sure the breathing air is safe

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Electric Shock

• The voltage used in welding 120 575 V
• The current used in welding 150 500 A

• Possible effects of electric shock
• Spasms
• Burns
• Muscle paralysis
• Death

• How to avoid
• Properly install and ground the equipment
• Wear dry, hole-free, insulating gloves and
• protective clothing
• Insulate yourself from the work piece
• and ground

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Radiation

• Radiation is electromagnetic energy given off
  by the arc or flame that can injure eyes
• and burn skin. Operator does not see
  ultraviolet and infrared radiation. Radiation is
  often
• silent and undetected, yet injury occurs.
  Two type of radiation Ionizing, Nonionizing.

• Possible effects of radiation
• Skin burns
• Eye damage
• Skin cancer
• Symptoms sand in the eyes, feeling of pressure
  in the eyes, tearing, photophobia
• How to avoid
• Use welding helmet with correct shade of
  filter plate
• Protect skin with adequate gloves and
  clothing
• Be aware of reflections from welding arcs

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Noise

• In welding noise may result from the process,
  the power source, or other equipment.
• Excessive noise is a known health hazard.

• Possible effects of noise
• Loss of hearing that may be either full or
  partial and either
  temporary or permanent
• Hearing loss may be a temporary threshold shift
  from which
  the ears may recover if removed from
  the noise source
• How to avoid
• Shield the source where practical
• Reduce the intensity of the source
• Use earmuffs

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Fire and Burns

• Welding processes produce molten metal, sparks,
  slag, and hot work surfaces. These can cause fire
  or burns.

• How to avoid fire
• Remove combustible materials for a minimum radius
  of 10.7 meters around the work area
• Cover or block all openings, such as doorways,
  windows, cracks, or other openings with
• fire resistant material
• Do not weld on or cut material having a
  combustible coating or internal structure

• How to avoid burns
• Wear dry, hole-free insulating gloves
• Wear oil-free protective garments such as leather
  gloves, heavy shirt, cuffless pants,
• high shoes, and a cap
• Use approved helmets and safety goggles

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Personal Protective Equipment
Respiratory protection
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Personal Protective Equipment
Eye safety
Safety eyewear should always be worn under the
welding helmet to protect against flying debris
when the helmet is raised to inspect work and
when engaged in other welding activities, e.g.
grinding, hammering.
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274 Le Conte Hall

• Oxy-fuel welding and cutting safety
• (flame temperature 2000 C)
• Before using an oxyhydrogen setup, ensure that
  
• flammable materials such as grease, oil,
  paint,
• sawdust, etc are cleared from the area
• Use enough ventilation or exhaust
• Shaded goggles with enclosed sides to protect
• your eyes from glare sparks and splatter
• Wear leather gloves to protect your hands from
  
• burns. Clothes and shoes/boots appropriate
  for
• welding.

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Soldering

• Soldering safety (about 400C)
• Work only in well-ventilate areas
• Use soldering support
• Avoid touching the mains flex
  with the tip of the iron
• Always return the soldering iron to its stand
  when not in use
• Wash your hands after using solder

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Resources

• EHS 0243 - Soldering Awareness Training
• The American Welding Society
• http//aws.org/w/s/technical/facts/inde
  x.html
• Welding Guideline
• www.gov.mb.ca/labour/safety/pdf/weldin
  g_guide.pdf

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