MIG welding is a highly flexible process, suitable for a broad range of metals, both thick and thin, and can be performed at high speeds. As such, it has become the most prevalent welding process in the industry. However, like all welding methods, it generates hazardous fumes that must be managed according to the guidelines set by health and safety organizations such as OSHA and ACGIH in the US, or CCOHS and CNESST in Canada.
Fume extraction guns present the most effective solution for MIG welding fume control. They allow welders to operate without the concern of adjusting a fume extraction device, thus ensuring consistent productivity. This technology not only shields welders from harmful fumes but also safeguards their colleagues.
The welding fumes are extracted immediately at the gas nozzle, through the handle, and a flexible hose encasing the power cable. The vacuum can be provided by either a portable or a central vacuum system. Apart from this, it operates similarly to a standard MIG gun.
In this article, I will also discuss the potential drawbacks of this technology and provide guidance on optimizing the use of fume extraction guns to ensure the safety of your welders, their colleagues, and maintain a cleaner, safer working environment.
Advantages of Fume Extraction Mig Guns
Safety for Welders and Surrounding Personnel
The primary advantage of using a fume extraction MIG gun is the protection it offers workers from the inhalation of dangerous fumes. As per a report by the Centers for Disease Control and Prevention (CDC), welding fumes are classified as carcinogenic.
Previously, companies largely relied on general ventilation to dissipate these fumes. While better than nothing, it doesn’t effectively remove the fume from the welder’s immediate environment or prevent it from spreading throughout the facility.
A fume extraction MIG gun addresses this problem by eliminating the pollutant at the source before it can be inhaled. Moreover, working in a fume-free environment is more comfortable and appealing, which can be an incentive to attract and retain employees.
Consistent Fume Extraction Efficiency
Unlike other external fume extraction methods such as flexible arms or nozzles, a fume extraction MIG gun ensures the extractor is always properly positioned and effective. On-tool extraction is suitable for any weld length or welding position. To learn more about arms and nozzles, refer to our article discussing the top solutions for MIG welding fume extraction.
No Need for External Extractor Adjustment
As mentioned earlier, flexible arms and nozzles need to be correctly positioned to work effectively. This adds an extra step for the welder who must reposition the fume extractor before each weld. If overlooked, fume extraction will be inefficient. With a fume extraction MIG gun, welders can continue their work as usual. Their regular operations remain unaffected, except that fumes are now managed effectively!
Reduced Airflow Requirement
Compared to other extractors and, to some extent, to general ventilation, fume extraction MIG guns require considerably less airflow. A rough guide would be 100 cfm for each gun compared to hundreds for each arm or nozzle and thousands for general ventilation. This may seem insignificant, but it has a substantial impact on your cost.
With filtration, less airflow equates to a smaller dust collector, which is less expensive to purchase and operate. Sending less air outside also means less air to reintroduce, resulting in significant heating or cooling cost reductions.
Disadvantages of Fume Extraction Mig Guns
Initial Investment and Need for New Welding Guns
One drawback of fume extraction MIG guns, which can deter companies from implementing them, is the need to replace the welding guns in a manufacturing plant. Moreover, it’s not possible to modify standard MIG torches for fume extraction.
Although the benefits outlined earlier justify the investment, it can require a considerable initial outlay for new welding guns, parts, and a vacuum system.
Some welders may be reluctant to adopt a new tool, even if it’s for their own safety. Effective education and training can help alleviate this concern.
Risk of Porosity
When extracting welding fumes, there’s a chance that the shielding gas may also be removed. If this protective layer is disrupted, it could lead to porosity, a significant problem. Therefore, choosing the correct fume extraction MIG gun and vacuum unit to deliver the right performance is vital.
I recommend selecting 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). This precaution minimizes the risk of the shielding gas being extracted along with the fumes. Most models also feature a bypass system, typically at the top of the handle, to decrease the airflow when welding in a confined area where less extraction is needed.
Compared to a standard MIG gun, a fume extraction one requires additional components. Consequently, it may be slightly heavier, although reputable brands like AIRGOMIG have successfully countered this. Notably, the power cable (the heaviest part of a torch) is cooled by the extracted air and can thus be smaller on a fume extraction MIG gun than on a conventional one, given the same parameters and performance.
The flexible hose adds some rigidity and should be attached to the handle with a ball or at least rotating joint to reduce strain on the welder’s wrist.
Recommendations for Choosing Your Fume Extraction MIG Gun
In conclusion, here are six tips to maximize the benefits of using fume extraction guns while mitigating the potential drawbacks.
- Select a fume extraction welding gun compatible with your welding parameters (power, gas, duty cycle).
- As stated before, choose a model where the vacuum nozzle is at least 2 or 3 inches from the end of the contact tip to prevent porosity.
- Ensure that you have at least 100 cubic feet per minute (cfm) in operation at the welding gun. The vacuum unit must provide this amount of airflow when the welding gun and flexible hose are installed (note, the operating airflow is not the same as the maximum airflow).
- Opt for a fume extraction gun that is lightweight and ergonomic, ideally with a ball or rotating joint for the flexible hose to minimize strain on the welder’s wrist. When comparing weights, consider only the section that the welder will be carrying (typically the handle and a few feet of power cable between the welder’s hand and the ground, not the entire MIG gun).
- Choose a model that is durable and easy to maintain. The number of parts and the amount of tools needed for maintenance are typically good indicators. For durability, allow your welders to test the brands you’re considering for a few days – you’ll quickly determine if they meet the criteria.
- Finally, if you’re using a portable vacuum unit, select one with an effective 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.