MIG is a very versatile process that enables welding a wide range of thick or thin metals at high speeds. Therefore, it is the most used welding process in the industry nowadays. However, like any type of welding, it generates hazardous fumes that need to be controlled as recommended by health and safety organizations such as OSHA and ACGIH in the US or CCOHS and CNESST in Canada.
Fume extraction guns are the best solution to extract MIG welding fumes. Welders can keep working without worrying about positioning a fume extraction device, which means no loss in productivity. Not only does this technology protects welders against toxic fumes, but it also protects their coworkers.
Welding fumes are extracted directly after the gas nozzle, through the handle and a flexible hose covering the power cable. The vacuum should be provided either by a portable unit or a central vacuum system. Other than that, it works like a conventional MIG gun.
In this article, I will also cover the downsides of this technology and how to make sure that you can make the best of fume extraction guns to protect your welders, their coworkers, and work in a cleaner and safer environment.
Pros of Fume Extraction Mig Guns
Protects the welder and people around
The most obvious benefit of using a fume extraction MIG gun is that it protects workers from inhaling hazardous fumes. According to a publication from the Centers for Disease Control and Prevention (CDC), welding fumes are classified as carcinogenic.
In the past, companies have primarily used general ventilation to evacuate these fumes. It is better than nothing but doesn’t remove the fume from the welder’s face as he works and does not prevent it from traveling in the plant either.
A fume extraction MIG gun does solve the issue by removing the pollutant at the source before anyone can breathe it. In addition, working in a fume-free environment is much easier and more pleasant. It can even be an argument to hire and retain employees.
Fume extraction is always efficient
Unlike external fume extraction technologies such as flexible arms, or nozzles, with a fume extraction MIG gun, the extractor is always well positioned and efficient. On-tool extraction works for every weld length and position. Learn more about arms and nozzles in our article introducing the best solutions for MIG welding fume extraction.
No external extractor to move
Like I just said, flexible arms and nozzles require to be well positioned to be efficient. Not only does it add a step for the welder who must move the fume extractor before every weld. But if forgotten, fume extraction will be inefficient. With a fume extraction MIG gun, welders can keep working as they used to. It’s business as usual (except that fumes are dealt with)!
Compared to other extractors and, to an extent, to general ventilation, fume extraction MIG guns require a lot less airflow. As a rule of thumbs each gun would require 100 cfm versus hundreds for each arm or nozzle and thousands for general ventilation. This might seem like a detail, but it dramatically impacts your cost.
When using filtration, less airflow means a smaller dust collector, which is cheaper to buy and operate. Sending less air outside also means less air to bring back in and, therefore, a significant reduction in heating or cooling costs.
The air passing through the gun also acts as a coolant. It is excellent for lowering the overall heat in the tool, which tends to increase the durability of consumables and the gun’s duty cycle. It is one of the strategies we recommend to prevent MIG gun overheating.
If you have any questions about welding fume, do not hesitate to contact us. We will be happy to give you some insight, and we can even visit you for free in the US and Canada.
Cons of Fume Extraction Mig Guns
Investment and New Welding Guns
A downside of fume extraction MIG guns, which sometimes stops companies from using them, is that it requires changing the welding guns in a manufacturing plant. In addition, it is impossible to adapt standard MIG torches to add fume extraction.
Although it is worth it for all the reasons mentioned above, it can require a significant initial investment in welding guns, parts, and a vacuum system.
Some welders can also resist change and do not always welcome a new tool, even if it is meant to protect them. Education and proper training will go a long way to mitigate this.
Beware of Porosity
When extracting welding fumes, there is a risk that shielding gas could be extracted too. Removing this protection could create porosity which is a major issue. Therefore, selecting the right fume extraction MIG gun and the vacuum unit that will give you the proper performance is crucial.
I recommend choosing a model where the vacuum nozzle is at least 2 to 3 inches away from the weld pool (or the end of the contact tip). Doing so reduces the risk of extracting shielding gas with the fumes. Most models also come with a bypass system, usually on the top of the handle, to reduce the airflow when welding in an enclosed spot where less extraction is needed.
Compared to a conventional MIG gun, a fume extraction one requires a few extra parts. As a result, it can be a bit heavier, although good brands such as AIRGOMIG have proven this to be wrong. Especially since the power cable (the heaviest part of a torch) is cooled by the extracted air and, therefore, can be smaller on a fume extraction MIG gun compared to a conventional one for the same parameters and performance.
The flexible hose also adds rigidity and should be fixed to the handle with a rotating joint to reduce the stress on the worker’s wrist.
Tips to Choose your Fume Extraction MIG gun
To sum up, here are six tips to take advantage of all the pros of using fume extraction guns while avoiding the downsides.
- You want to pick a fume extraction welding gun that will work for your welding parameters (power, gas, duty cycle).
- As mentioned earlier, choose a model where the vacuum nozzle is at least 2 or 3 inches from the end of the contact tip to avoid porosity.
- Ensure that you have at least 100 cubic feet per minute (cfm) in operation at the welding gun. The vacuum unit must provide that amount of airflow when the welding gun and flexible hose are installed (be careful, the operating airflow is not the same as the maximum airflow). You can also check our resource helping you choosing between a portable or stationary vacuum unit.
- Pick a fume extraction gun that is light and ergonomic, ideally with a ball or rotating joint for the flexible hose to reduce the stress on the worker’s wrist. When comparing weights, only consider the section that the welder is carrying (usually the handle and a few feet of power cable between his hand and the ground, not the whole MIG gun).
- Choose a model that is tough and easy to maintain. The number of parts and quantity of tools needed for maintenance operation are usually good indicators. When it comes to resistance, just let your welders try the brands you are considering for a few days, you will know very quickly if they pass the test.
- Finally, if you use a portable vacuum unit, pick one with an efficient filter (MERV-12 or above) that has at least 100 sq. ft. of surface per gun (ideally more).
Feel free to contact us. We will help you protect your workers and comply with welding fumes standards anywhere in the US and Canada.