Robotic Welding
Facts on Welding Smoke and Fumes:
- Robotic, and Automated Weld processes create smoke and fumes.
- Similar to Manual Welding, many of the same core principles apply
- The following factors affect how hazardous the smoke and fumes are;
- Weld Process (MIG / TIG / Laser Welding, etc.)
- Material being welded (Mild or Carbon Steel / Stainless Steel / Aluminum, etc.)
- Material thickness.
- Consumables (wire / electrodes / shielding gas etc.) being used.
- Weld parameters (amperage, weld speed, heat etc.)
- Location of workers in relation to the weld process
- Coatings on the material
- Amount of oil on material
- Exposure to welding fumes can cause numerous health problems. When inhaled, welding fumes can enter the lungs, bloodstream, brain nerve cells, spinal cord and other organs and can cause both short- and long-term health effects – read more at ASSE / Welding Fume Risks
THE FOLLOWING SUBSTANCES MAY BE FOUND IN WELDING FUMES:
| FUME TYPE | SOURCE | HEALTH EFFECT |
|---|---|---|
| Aluminum | Aluminum component of some alloys, e.g., Inconels, copper, zinc, steel, magnesium, brass and filler materials. | Respiratory irritant. |
| Beryllium | Hardening agent found in copper, magnesium, aluminum alloys and electrical contacts. | “Metal Fume Fever.” A carcinogen. Other chronic effects include damage to the respiratory tract. |
| Cadmium Oxides | Stainless steel containing cadmium or plated materials, zinc alloy. | Irritation of respiratory system, sore and dry throat, chest pain and breathing difficulty. Chronic effects include kidney damage and emphysema. Suspected carcinogen. |
| Chromium | Most stainless-steel and high-alloy materials, welding rods. Also used as plating material. | Increased risk of lung cancer. Some individuals may develop skin irritation. Some forms are carcinogens (hexavalent chromium). |
| Copper | Alloys such as Monel, brass, bronze. Also some welding rods. | Acute effects include irritation of the eyes, nose and throat, nausea and “Metal Fume Fever.” |
| Fluorides | Common electrode coating and flux material for both low- and high-alloy steels. | Acute effect is irritation of the eyes, nose and throat. Long-term exposures may result in bone and joint problems. Chronic effects also include excess fluid in the lungs. |
| Iron Oxides | The major contaminant in all iron or steel welding processes. | Siderosis – a benign form of lung disease caused by particles deposited in the lungs. Acute symptoms include irritation of the nose and lungs. Tends to clear up when exposure stops. |
| Lead | Solder, brass and bronze alloys, primer/coating on steels. | Chronic effects to nervous system, kidneys, digestive system and mental capacity. Can cause lead poisoning. |
| Manganese | Most welding processes, especially high-tensile steels. | “Metal Fume Fever.” Chronic effects may include central nervous system problems. |
| Molybdenum | Steel alloys, iron, stainless steel, nickel alloys. | Acute effects are eye, nose and throat irritation, and shortness of breath. |
| Nickel | Stainless steel, Inconel, Monel, Hastelloy and other high-alloy materials, welding rods and plated steel. | Acute effect is irritation of the eyes, nose and throat. Increased cancer risk has been noted in occupations other than welding. Also associated with dermatitis and lung problems. |
| Vanadium | Some steel alloys, iron, stainless steel, nickel alloys. | Acute effect is irritation of the eyes, skin and respiratory tract. Chronic effects include bronchitis, retinitis, fluid in the lungs and pneumonia. |
| Zinc | Galvanized and painted metal. | Metal Fume Fever. |
“Welder’s Guide to the Hazards of Welding Gases and Fumes”
View Additional Resource Links & Downloads
The following links provide further information on OSHA’s regulations
The American Welding Society also makes available important information regarding safety in welding, they have available for free download the standard Z49.1:2012 – Safety in Welding, Cutting, and Allied Processes; http://www.aws.org/safety/
In additional, recommendations are made by the ACGIH (American Conference of Governmental Industrial Hygienists);
Tables of Regulatory and Recommended exposure limits for substances are available here:
The American Welding Society also makes available important information regarding safety in welding, they have available for free download the standard Z49.1:2012 – Safety in Welding, Cutting, and Allied Processes; http://www.aws.org/safety/
How to Control Welding Smoke and Fumes:
The type of equipment that is appropriate for your process depends on how hazardous the fume is, and how large the weldments are, as well as other factors. Some factors to note:
- Stainless steel, especially in MIG welding processes, generally requires source capture methods to control the fume very closely to keep low exposure to Hexavalent Chromium that is present in the fumes.
- Mild Steel can be controlled with Source Capture or Ambient and General Ventilation
Equipment to Control Robotic Welding Smoke and Fumes:
Source Capture Equipment:
- Fume arms are generally not appropriate to capturing fumes from automated processes, as they need to be positioned by a worker to keep near enough to the weld location to have effective capture.
- Overhead hoods are a very effective method in controlling smoke from welding robots as the smoke is kept in a contained environment, to be captured by an intake device in to the air filtration unit. Note that if workers are located within the enclosure, higher rates of ventilation may be required, to keep fume from exceeding Permissible Exposure Limits.