Presentation on theme: "Welding, Soldering, Brazing"— Presentation transcript:
1 Welding, Soldering, Brazing Max AkhterovZettl Group Safety Talk11/07/06
2 WeldingWelding 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 SocietyAWS distinguishes the welding processes according to:Mode of energy transferInfluence of capillary attraction in effecting distribution of filler metal in the jointGroups of welding processes:Arc weldingBrazingOxyfuel Gas WeldingResistance WeldingSolid State WeldingSolderingOther
3 Hazards 1. Fumes and Gases 2. Electric Shock 3. Radiation 4. Noise 5. Fire and Burns
4 Fumes and GasesFumes are solid particles which originate from welding consumables, the basemetal, and any coatings present on the base metal.Possible effects of over-exposure (magnesium, copper, zinc, lead, chromium, etc.):Irritation of eyes, skin, respiratory systemSymptoms: nausea, headaches, dizziness, metal fume fevermanganese overexposure can affect the central nervous systemresulting in impaired speech and movementIn confined spaces the gases might displace breathing air and cause asphyxiationHow to avoid:Do not breathe the fumesUse respiratory protectionUse enough ventilation or exhaustBe sure the breathing air is safe
5 Electric Shock The voltage used in welding: 120 – 575 V The current used in welding: 150 – 500 APossible effects of electric shock:SpasmsBurnsMuscle paralysisDeathHow to avoid:Properly install and ground the equipmentWear dry, hole-free, insulating gloves andprotective clothingInsulate yourself from the work pieceand ground
6 RadiationRadiation is electromagnetic energy given off by the arc or flame that can injure eyesand burn skin. Operator does not see ultraviolet and infrared radiation. Radiation is oftensilent and undetected, yet injury occurs. Two type of radiation: Ionizing, Nonionizing.Possible effects of radiation:Skin burnsEye damageSkin cancerSymptoms: “sand in the eyes”, feeling of pressure in the eyes, tearing, photophobiaHow to avoid:Use welding helmet with correct shade of filter plateProtect skin with adequate gloves and clothingBe aware of reflections from welding arcs
7 NoiseIn 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 permanentHearing loss may be a temporary threshold shift from which the ears may recover if removed from the noise sourceHow to avoid:Shield the source where practicalReduce the intensity of the sourceUse earmuffs
8 Fire and BurnsWelding 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 areaCover or block all openings, such as doorways, windows, cracks, or other openings withfire resistant materialDo not weld on or cut material having a combustible coating or internal structureHow to avoid burns:Wear dry, hole-free insulating glovesWear oil-free protective garments such as leather gloves, heavy shirt, cuffless pants,high shoes, and a capUse approved helmets and safety goggles
9 Personal Protective Equipment Respiratory protection
10 Personal Protective Equipment Eye safetySafety 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.
11 274 Le Conte Hall Oxy-fuel welding and cutting safety (flame temperature 2000 C):Before using an oxyhydrogen setup, ensure thatflammable materials such as grease, oil, paint,sawdust, etc are cleared from the areaUse enough ventilation or exhaustShaded goggles with enclosed sides to protectyour eyes from glare sparks and splatterWear leather gloves to protect your hands fromburns. Clothes and shoes/boots appropriate forwelding.
12 Soldering Soldering safety (about 400°C): Work only in well-ventilate areasUse soldering supportAvoid touching the mains flex with the tip of the ironAlways return the soldering iron to its stand when not in useWash your hands after using solder
13 Resources EHS 0243 - Soldering Awareness Training The American Welding Society:Welding Guideline: