How to remove welding fumes?
One can use local exhaust ventilation systems to get rid of fumes and gases from a welder’s breathing area. Fume extractor guns, vacuum nozzles, and fume hoods should be kept near the plume source to reduce the amount of fumes and gases. Usually, welding zones contain jib cranes, forklifts, overhead cranes and other handling equipment. With all these machines around, it becomes incredibly difficult for welding fume extractors to remove the harmful fumes and welding smoke.
Welding fumes are made up of fine condensed metallic particulate and other solid particles. Note that welding fumes are not gases, but gases such as NOx, carbon monoxide, and ozone are created during the welding process. Basically, a welder vaporizes part of the weld metal. In light of this, it is important that you understand and adhere to OSHA exposure guidelines for the above metals. And this is mainly because the employees risk suffering long-term health problems.
Keep in mind that it’s not all about keeping health issues at bay. During welding, the welding “smoke” or fumes contain hot dust particles that rise up and stick to the ceiling. After some time they cool and fall on floors, office furniture, paperwork or anything else that’s in the room.
A few years back, excessive weld fumes would be removed by opening the door and letting the fumes out in the open. Today, it’s quite different. Stricter EPA regulations have now been put in place to ensure that people don’t resort to such a solution. When fumes are exhausted outdoors, the area is closely monitored under the EPA National Emission Standard for Hazardous Air Pollutants (NESHAP) Rule 6x.
A common solution to get rid of welding fumes is the use of a fume extraction system.
They are great for applications that involve small parts and fixture welding. A flexible source capture arm or a complete enclosure around the setup will be utilized. For a robotic weld cell, for instance, you can use a glass enclosure. This might not be the best method because it is only suitable for smaller envelopes of approximately 5-ft cube at most.
For medium-sized footprint areas (say 12 ft. by 20 ft. or less), overhead hoods are perfect. If you want to create an enclosure or a booth, you can add hard walls or curtains to the sides. In most cases, adding such barriers is impossible as the workspace will be too small or the existence of equipment in the zone will be a hindrance.
Ambient Vacuum System
Some systems use a central system or multiple smaller collectors to filter all the air in the shop. Such systems equip facilities involved in multiple operations to capture all the fumes, so they usually selected to serve larger areas. Ambient collection is great for operations involving large parts, stitch welding and varied welding processes. During the winter, heat typically rises to the ceiling resulting in a cold factory floor. Ambient systems help distribute heat in all directions and this creates a great working environment.
Localized Air Amplifiers
The best approach for fume and smoke removal and dust collection is the use of an air amplifier. Here, the compact pneumatic device sucks in and exhausts large volumes of air using compressed air as its power source. A localized Air amplifier does not require much maintenance and will take you only a couple of minutes to install. With the aid of the coanda effect, they are able to hit a 25:1 amplification ration making them suitable for the job. In addition to that, electricity isn’t used so there is no shock hazard.
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