MIG welding stands out as the most prevalent welding method in the industrial sector. This versatile technique enables the welding of diverse metals, suits materials of various thicknesses, and ensures impressive metal deposition and welding speed.
Despite its advantages, MIG welding can produce significant amounts of harmful fumes. Thus, the adoption of fume extraction measures is either obligatory or strongly suggested by health and safety bodies across all US states and Canadian provinces.
The most effective strategiy for MIG welding fume extraction is utilizing a fume extraction MIG gun. This on-tool extraction approach guarantees optimal results as the extractor is consistently well-positioned, regardless of weld length or position. An High Vacuum Low Volume (HVLV) system is needed to supply the required vacuum.
This article also introduces other proficient fume extraction strategies for MIG welding and offers guidance on choosing the appropriate extractor and vacuum unit for the best performance.
Top Three Fume Extraction Approaches for MIG Welding
Fume Extraction MIG Guns
Fume extraction MIG guns stand out as the best solution for extracting welding fumes for this process. They allow welders to continue working without worrying about positioning a fume extraction device, maintaining productivity. The absence of fumes even enhances efficiency by providing a clearer view of the process and a more comfortable working environment.
These fume extraction guns draw out welding fumes right after the gas nozzle, through the handle, and a flexible hose that covers the power cable. The vacuum can be supplied by either a portable unit or a centralized vacuum system.
Selecting the Right Fume Extraction Gun
Here are some tips to help you select the best fume extraction MIG gun. First, it’s crucial that the gun doesn’t cause porosity. To prevent this, we recommend choosing a model where the vacuum nozzle is a minimum of 2 to 3 inches from the weld pool, reducing the risk of extracting shielding gas along with the fumes.
For the best results, ensure your fume extraction MIG gun has sufficient airflow. Ideally, you want at least 100 cubic feet per minute (cfm) in operation (when the nozzle is 2 to 3 inches away from the weld pool). This means your vacuum unit must deliver 100 cfm when the welding gun and flexible hose are installed (the unit’s maximum airflow should be significantly higher considering the substantial pressure drop of the system). The exact airflow required depends on multiple factors, such as welding power (higher parameters demand more airflow) and the welding position (horizontal welding in a corner is easiest to control, whereas vertical welding is more challenging).
Since a fume extraction gun requires some additional parts not found on a traditional MIG gun, you’ll want to ensure that the new torch isn’t excessively heavy. The flexible hose, which adds rigidity, should be attached to the handle with a rotating joint to ease stress on the worker’s wrist.
Finally, pick a fume extraction welding gun that suits your welding parameters, withstands tough manufacturing environments, and is easy to maintain. If you use portable units, choose one with an efficient filter (MERV-12 or higher) and at least 100 sq. ft. of surface (ideally more).
The Top Two Brands
The AIRGOMIG fume extraction MIG gun is likely the best on the market. It is ergonomically designed, highly efficient, and ensures unmatched fume extraction results without causing porosity. It can be used with either one of Henlex’s powerful portable units or a central vacuum unit, both capable of providing the necessary performance even with high welding parameters.
A good alternative is the Abicor Binzel xFUME MIG guns. While they may not be as efficient or ergonomic as AIRGOMIG, they come close in terms of results. They could be a viable option, particularly for manufacturers already using Abicor Binzel guns and parts. Note, however, that at the time of writing this article, air-cooled fume extraction guns were only available for up to 300 Amp (compared to 500 Amp for AIRGOMIG).
Pros & Cons
- Maximum efficiency with minimal airflow
- Suitable for any weld length, parameters, and position
- No need to reposition an extractor
- Requires changing your welding guns
- The extraction gun must be selected carefully to avoid porosity
Learn more about pros and cons of fume extraction MIG guns here.
Fume Extraction Arms for MIG Welding Fumes
Flexible arms, while not as efficient as fume extraction MIG guns, are the most commonly used method to extract MIG welding fumes. They can perform effectively but must always be correctly positioned to function optimally, often causing their efficiency and usability to fall short.
Unlike fume extraction guns that require high vacuum and low air volume, flexible arms demand less pressure but a much larger airflow. As a result, they are typically used with more traditional vacuum blowers.
Choosing the Right Fume Extraction Arm
Three main factors should be considered when choosing a fume extraction arm. First, consider the diameter – the smaller, the better, for three reasons: it occupies less space, requires less airflow, and is more cost-effective to purchase and operate. A general rule is to take your longest usual horizontal weld, divide it by three, and use that as your diameter. For example, if each weld is never or rarely over 9 inches long, a 3-inch arm would be perfect. This way, you reap all the benefits without having to adjust the arm during welding.
The second factor is ensuring sufficient airflow for the flexible arm’s efficiency. While it depends on multiple factors, we suggest ensuring you get at least the arm diameter minus one, multiplied by 100 cfm in operation (meaning the blower should be able to provide it while the arm is in use, which implies the maximum airflow must be higher). So, for a 3” arm, (3-1) x 100 = 200 cfm minimum. For a 6” arm, (6-1) x 100 = 500 cfm minimum.
Lastly, we recommend avoiding arms made of plastic or flexible hose as they aren’t suitable for use in a manufacturing environment and would require extensive upkeep and maintenance.
The Top Four Brands
Henlex Capture Arms and blowers are designed to excel in any welding environment. The exterior components are exclusively made of metal for unmatched durability. Henlex also provides a range of blowers designed to offer the required extraction performance for MIG welding fumes.
Miller, Plymovent, and Nederman’s arms might not be as durable (as they are made with hose and plastics) as Henlex’s, but they could be viable alternatives when used with the correct blower. These brands all offer different configurations and some beneficial options. However, some of these brands tend to advocate for larger arms, which comes with its own set of downsides, as explained earlier.
Pros & Cons
- Highly efficient if correctly positioned
- No need to change your welding guns
- Suitable for other welding processes
- More costly to purchase and operate (due to the high airflow needed for efficiency)
- Occupies more space and may obstruct the welder’s view
- Not suitable for enclosed or cluttered spaces
Fume Extraction Nozzles for MIG Welding Fumes
If you opt against using a fume extraction MIG gun and work in a confined or cluttered space that makes using a flexible arm unfeasible, a fume extraction nozzle could be the solution. Connected to a portable vacuum unit with a flexible hose, it’s likely the most economical alternative. However, it’s crucial to note its main limitation: it’s only efficient if the nozzle is positioned close to the weld pool and will only work for a weld length of a few inches. It also necessitates frequent repositioning, which can significantly reduce efficiency as welders often forget to do so.
Choosing the Correct Fume Extraction Nozzle
The guidelines mentioned for flexible arms also apply to fume extraction nozzles in terms of materials (except for the flexible hose, which is required in this case), diameter, and airflow.
Several companies, including Henlex, provide fume extraction nozzles and portable extractors. Choose a system with the proper operating airflow (distinct from the maximum airflow) and largest surface filtration for maximum efficiency.
Pros & Cons
- Economical and versatile solution
- No need to change your welding guns
- Suitable for other welding processes
- Limited efficiency
- Only works for small weld lengths (maximum of a few inches)
- Requires frequent repositioning
Downdraft Tables and Hoods are NOT suitable for MIG Welding Fumes
There is a common misconception that downdraft tables are suitable for welding fume extraction. However, it’s impractical to extract fumes that naturally rise at a high speed due to the generated heat from below. Therefore, either downdraft tables are ineffective for welding fumes, or the airflow required to make them efficient is prohibitively expensive. Downdraft tables could be used for plasma cutting or a grinding workstation, but they aren’t recommended for welding.
Generally, fume extraction hoods cannot protect a welder as their head would be between the welding area and the hood. However, they are ideal for robotic welding, offering unmatched fume extraction efficiency in such cases.
Do You Need a Dust Collector for MIG Welding Fumes?
While there is no definitive answer to this question, here are a few guidelines that can help you decide.
You may want to recirculate the extracted air inside your building rather than sending it outdoors. Usually, companies opt for this for two reasons. The first is to save on heating or cooling costs as extracted air needs to be replaced with outdoor air. The second is environmental concerns. To recirculate the extracted air, you’ll need a dust collector to filter the MIG welding fumes before reintroducing the air.
When the extracted air is sent outside, you should ensure it’s in accordance with company standards, such as ISO 14001, and local environmental laws. In the United States, you should follow the regulations of the United States Environmental Protection Agency. Air sampling might be necessary to determine the quantity and concentration of welding fumes your process expels outdoors.
Feel free to contact us. We will help you protect your workers and comply with welding fumes standards anywhere in the US and Canada.