7.14 Smoke Extracting Systems
The GMAW process can generate some smoke. Flux cored arc welding (FCAW) often produces quite a bit of smoke. When welding with carbon dioxide (CO2), there is some carbon monoxide (CO) created. Some ozone is also created. Both of these gases are toxic. It is especially important to prevent breathing these gases or any metal or metal oxide fumes.
Removal of these gases from the weld area can be done by means of a GMAW gun equipped with a fume extractor. Fume extractors may be built into the gun, as shown in Figure 7-61. Gas fumes, contaminated air, and air near the weld are drawn away by the torch, filtered, and released to the atmosphere. Figure 7-62 shows a fume extractor in use.
Another method to remove fumes is to use a large fume extractor system, as shown in Figure 7-63. The pickup hood can be located near the welding area to remove the contaminated air. This type of exhaust system can be used with any welding process or other process in the welding shop, such as grinding.
An inexpensive option to move fumes away from the welder is to use a portable fan. This does not eliminate the fumes, only moves them. The fan cannot blow too much air or it will blow the shielding gas away from the weld and cause contamination of the weld.
Sometimes, welding must be done in a closed or confined area, or on metals that are hazardous. In such cases, it is necessary for the welder to wear an air-supplied breathing apparatus to supply fresh, clean air. Chapter 1 contains information on breathing apparatus.
Whenever it is necessary to use an air-supplied respirator, always make sure the system is operating properly before entering a closed, confined, or contaminated area and before doing any welding. Caution: Remember that an air-purifying respirator does not remove toxic fumes and should not be used for protection in a closed, confined, or contaminated area.
The GMAW process can generate some smoke. Flux cored arc welding (FCAW) often produces quite a bit of smoke. When welding with carbon dioxide (CO2), there is some carbon monoxide (CO) created. Some ozone is also created. Both of these gases are toxic. It is especially important to prevent breathing these gases or any metal or metal oxide fumes.
Removal of these gases from the weld area can be done by means of a GMAW gun equipped with a fume extractor. Fume extractors may be built into the gun, as shown in Figure 7-61. Gas fumes, contaminated air, and air near the weld are drawn away by the torch, filtered, and released to the atmosphere. Figure 7-62 shows a fume extractor in use.
Another method to remove fumes is to use a large fume extractor system, as shown in Figure 7-63. The pickup hood can be located near the welding area to remove the contaminated air. This type of exhaust system can be used with any welding process or other process in the welding shop, such as grinding.
An inexpensive option to move fumes away from the welder is to use a portable fan. This does not eliminate the fumes, only moves them. The fan cannot blow too much air or it will blow the shielding gas away from the weld and cause contamination of the weld.
Sometimes, welding must be done in a closed or confined area, or on metals that are hazardous. In such cases, it is necessary for the welder to wear an air-supplied breathing apparatus to supply fresh, clean air. Chapter 1 contains information on breathing apparatus.
Whenever it is necessary to use an air-supplied respirator, always make sure the system is operating properly before entering a closed, confined, or contaminated area and before doing any welding. Caution: Remember that an air-purifying respirator does not remove toxic fumes and should not be used for protection in a closed, confined, or contaminated area.