Welding fume extraction – challenges and opportunities
The Complete Guide to Fume Extraction
When it comes to controlling air quality, welding fume extraction is becoming increasingly important in industrial production. Welders and other employees in the production hall are exposed to these dangerous fumes, which can even cause permanent damage to health, such as cancer. Everyone must be protected from welding fumes. The regulations for this have become even stricter. But where do you start when dealing with this topic for the first time? What can be done to ideally collect welding fumes at the source of their origin and prevent them from spreading? And what options are available?
Download the free eBook that covers the various options available. Get information on the key performance metrics and the most effective method of fume extraction at the source, called spot extraction. This eBook is aimed at Management, Production Managers, Safety Officers, Health and Safety Representatives and welders alike. It is a very helpful resource for everyone - whether you are new to welding fume extraction or would like to find out more about the innovative fume extraction technology. This eBook will give you a comprehensive overview of the challenges and opportunities of welding fume extraction - and you will be ahead in the topic of active health protection.
... or scroll down to read the complete guide.
- About the authors
- From standard welding to fume extraction welding
- Solutions for welding fume extraction
- High vacuum systems vs. low vacuum systems
- Central fume extraction systems
- Mobile fume extraction systems
- LEV systems/fume extraction arms
- Extraction at the source vs. local extraction
- Welding fume extraction with manual welding torches
- Fume extraction for welding robots
- Welding fume extraction for “hard automation”
- Welding fume extraction for TIG welding
- Legal requirements
- Fume extraction – FAQs
- Editorial team
Head of Extraction Technology, Alexander Binzel Schweisstechnik GmbH & Co. KG, Alten-Buseck
André Faber is the Head of Extraction Technology at ABICOR BINZEL. He has worked in the welding industry for more than 15 years, initially as a development engineer and then as a Product Manager for manual products at ABICOR BINZEL. He graduated from the TH Mittelhessen University of Applied Sciences (THM) with a degree in mechanical engineering.
Product Manager Extraction Technology, Alexander Binzel Schweisstechnik GmbH & Co. KG, Alten-Buseck
Florian George started his professional career seven years ago in the automotive industry. Initially in design and development, later in technical sales. During this time, he successfully completed his studies as a “State-examined industrial engineer – in the field general mechanical engineering”. Since the beginning of 2021, Florian George has been Product Manager in the Extraction Technology department at ABICOR BINZEL and is responsible for the extension, strategic expansion and maintenance of the product portfolio.
Over the past few years, health and safety issues have become more and more important. Scientific studies and findings about the effect of welding fumes on health have led to legal regulations and limit values being adapted. In the meantime, companies are obliged to implement health-conscious welding fume extraction in their production process.
The development of technical solutions to reduce welding fume emissions is in full swing – as is the development of extraction solutions. There is a large range of extraction technology solutions on the market, and advanced developments are coming along in leaps and bounds. In this eBook we would like to give you an idea of the current status quo so that you can find the extraction technology solution best suited to your needs.
We expect the health and safety requirements to be made even more stringent in the near future – worldwide. Now is the time to adapt welding production to the individual guidelines applicable for countries and regions, and to protect welders and all those working in their direct vicinity from harmful fumes.
Fume extraction is the term used for the elimination of fumes – caused either by welding, cutting or grinding – from the work area to keep them from being inhaled by workers even at workstations further away in the production hall. During welding, components form an inseparable joint through the application of heat with or without filler materials. During this process, fumes are released mainly from the filler material used, but sometimes also due to chemical reactions.
Some fumes are clearly visible, others cannot be seen by the human eye. The fact that they cannot be seen doesn’t make them less hazardous however. This distinction becomes very clear during MIG/MAG welding and TIG welding: whereas a relatively large amount of fumes is produced during MIG/MAG welding, the less visible to invisible fumes produced during the TIG welding of stainless steels, for example, are extremely carcinogenic. Welding parameters, wire, gas, base material and filler materials all impact the quantity and exposure of fumes during welding.
At the end of the day, it doesn’t matter whether the fumes are visible or not. It is essential to protect workers from inhaling these harmful welding fumes.
In principle, fume extraction is required wherever welding work of any kind is being done. This can be during college training to become a welding expert, minor welding work in a repair workshop or in a large manufacturing company with lots of welding workstations. There are large and small, simple and complex fume extraction solutions for every application, to remove hazardous welding fumes from the working environment.
Fume extraction isn’t just a workplace benefit, it also protects your workers from serious health risks. A 2019 cohort analysis study in the Occupational and Environmental Medicine journal looked at over 17 million welders worldwide from Germany to France to the United States and found that welders and people exposed to welding fumes were 43 percent more likely to develop lung cancer than the average population.
Workers are exposed to more hazards in addition to welding fumes. The International Agency for Research on Cancer (IARC) – an expert department of the World Health Organisation (WHO) – classified the UV radiation released during welding as the highest risk level for cancer back in 2012. At this time, welding fumes were only considered “possibly carcinogenic”. The IARC has now adjusted this and also classifies welding fumes as the highest risk level for the development of cancer in humans (human carcinogen).
When it comes to fume extraction, there are a lot of reservations and even false information around. Welders are reluctant to try out special welding fume extraction torches because they imagine these will be heavy and unwieldy torches that only allow poor accessibility to the weld seam. In reality, technology is now so far advanced that individual manufacturers supply extraction torches which are almost identical to handle as comparable standard welding torches.
This guide will take you through all the facts on current findings and developments to help you choose the technology solution best suited to your individual needs.
People often worry that integrating fume extraction into the welding operation will have a negative impact on the weld seam result. This is not the case – neither the quality of the weld seam is impacted nor is pore formation more common. The welding result is just as good as welding with a comparable MIG/MAG standard torch.
When welding with a fume extraction torch, however, the following points need to be taken into consideration:
- The holding time at the end of a weld seam must be extended somewhat for the post-exposure of the welding fumes to be collected
- The welding position must be adapted as far as possible to be able to achieve the best possible extraction of the harmful welding fumes
Metals like stainless steel or high-alloy steel – which contain iron, chrome, nickel and manganese – develop extremely harmful welding fumes. A suitable system for proper fume extraction is always necessary in this case, so that these pollutants are collected safely and can be disposed of properly and in line with requirements.
Anything involving chrome or nickel extraction must be IFA-W3 certified. Hexavalent chrome in particular (usually referred to as Cr-VI) is very harmful. It is present in all stainless steel and is a known cause of cancer according to a wide range of scientific research. For this reason, it is mandatory to use an extraction system with W3-certified filter which can eliminate these harmful particles when the CrNi content is above 30%.
Galvanised steel is also a hazardous material where it is important to extract the harmful welding fumes produced during the welding process. When zinc is welded, for example, it releases zinc oxide fumes which can cause fume metal fever like exposure to manganese, copper or beryllium does, and damage the respiratory system. Other metals like lead, which can be used like zinc as a coating on certain metals, can even damage the central nervous system.
When aluminum is welded, aluminum oxide is released, which can lead to respiratory and lung disease when inhaled. In the worst case, aluminosis or aluminum pneumoconiosis can occur. As so-called A-dust, these particles get into the lung alveoli and change lung tissue, even shrinking the tissue affected. Lung cancer can be a long-term consequence of this. In addition, an increased amount of ozone is produced during the welding of aluminum under UV radiation; this is also harmful to health. Recent studies have shown that ozone can be efficiently extracted from the welding area.
Often, aluminum is welded with push-pull torches, because the wire is very soft in its texture compared with steel wire. There are no push-pull torches with integrated welding fume extraction available as yet, but they can be ideally equipped with a fume extraction kit such as the fume extraction kit from ABICOR BINZEL. This is simply clamped to the torch neck so that the fumes can be extracted at their source.
RAS with different extraction nozzles
A further alternative for extraction when a push-pull torch is used is the xFUME® FLEX extraction system, the flexible extraction arm of which can be positioned above the welding process.
The extraction arm of the xFUME® FLEX is available in lengths of two, three and four metres
The welding fume extraction systems FES-200 W3 and FEC W3 were specially developed to meet the demands of welding stainless steel and other alloys which also contain a large amount of chrome and nickel. In combination with a welding fume extraction torch, these systems are considered approved by the statutory accident insurance institutions for the extraction of highly carcinogenic fumes. In Germany, W3-certified welding fume extraction systems may supply the filtered exhaust air back to the work area in compliance with TRGS 528.
Non-alloyed steel, alloyed steel with alloy components
|Same as W1, plus alloyed steel with alloy components
e.g. Ni and Cr (5% ≤ x ≤ 30%)
|Same as W2, plus alloyed steel with alloy components
e.g. Ni and Cr (high-alloy steel with x ≥ 30% Ni-based alloys)
FES-200 W3, xFUME® ADVANCED W3 and FEC W3 are certified by the Institute of Work Safety (IFA) and thus approved for use with high-alloy chrome-nickel steels.
Do you have to change your current working set-up in order to implement fume extraction? No, that is not necessary. You can use the same processes, protocols and systems you were previously using for your MIG/MAG welding torches and seamlessly integrate fume extraction.
A general rule is that the higher the amperage used, the more harmful are the welding fumes emitted into the ambient air. Accordingly, during some welding processes more fumes are produced than during others.
The integration of welding fume extraction at an existing workstation is easier than you think.
Is it necessary to purchase new equipment to implement fume extraction? Yes. However, this does not mean that the welding parameters or set-up have to be changed. Ideally, you would buy a fume extraction system and a fume extraction torch in order to achieve the best possible solution with extraction at the source.
Pay attention to the position of the extraction torch during welding in order to extract the greatest possible quantity of welding fumes. And at the end of a weld seam remain for a little longer in position than you are used to with MIG/MAG standard welding torches, so that the residual welding fumes are extracted as well.
If welding fume extraction at the source is not an option for you, systems with extraction arms offer a further solution. Ideally, the welding fume extraction system should get as close as possible to the source to prevent the welding fumes from spreading. The closer welding fume extraction is to the “source” the better. More details can be found in the chapter »Solutions for welding fume extraction«.
Professional respiratory masks can provide additional protection and supplement an extraction arm.
When choosing a respiratory mask, care must be taken that it has been approved for the European market. For this to be guaranteed, it must have CE certification and an EC Declaration of Conformity. Respiratory masks are personal protective equipment (PPE) and belong to category 3, which means they are subject to EC type test certification. Usually, half-masks, powered air-purifying respirators (APR) and supplied-air respirators (SAR), which are independent of the ambient air, are considered when dealing with welding fumes. When using these respiratory masks, remember that cartridges and filters have to match the respective pollutant they are protecting against and have to be changed periodically.
In addition, respiratory devices are usually a last resort solution and, according to the European Centre for Disease Control (ECDC), should be used when fume extraction torches and systems are not feasible.
However, if workstation limits are exceeded, respiratory masks are not permitted either. In other words, this type of protection against harmful welding fumes is not a standalone solution.
Respirators protect the welder, but not his working environment
Before using a respiratory mask, check first whether it really fits snugly. As the employer or person responsible, make sure the welder does not have any heart or lung conditions that could make wearing a respirator dangerous. Occupational medical check-ups will allow you to be certain that your employees can work with a respirator, for example. This check-up must take place in a protected room and under the confidentiality of the company doctor. It aims to recognise health issues at an early stage and prevent work-related illness.
Absolutely. The health-related benefits of the use of welding fume extraction are undeniable. During welding, pollutants such as iron oxides, lead oxides, manganese, nickel oxides, chrome (VI) compounds, thorium oxide, beryllium oxide, nitrogen oxide, hydrogen cyanide, ozone, phosgene, methanal, carbon monoxide, carbon dioxide and many more are produced. If these get into the respiratory organs – and depending on the size of the particles they can get into the lung alveoli or even the blood – they deposit, interfere with gas replacement and can lead to serious health problems or illnesses.
The hazard always depends on the metal involved, the welding position and the respective welding area (inside, outside, in a closed room etc.), but this doesn’t make it any less present.
The choice of a suitable extraction solution is crucial for efficiency and the objective of fulfilling the requirements of local health and safety regulations. With hood extraction, for example, there is a risk of the welder sitting or standing between the welding process and the extraction hood and thus directly in the fume flow. In this case, fume extraction does not achieve the necessary effect. By using extraction solutions with fume collection directly above the process – so-called extraction at the source – up to 90% of the fumes do not even reach the environment and cannot be inhaled. Further welding fume extraction possibilities currently available will be described in the next chapter.
Whether centralised or portable, there is a fume extraction system to suit every welding process and workplace.
There are different possibilities available for extracting welding fumes. A basic distinction can be made here between two extraction systems: high vacuum systems and low vacuum systems.
The terms high vacuum systems and low vacuum systems refer specifically to the static pressure. In a high vacuum system, there is a low volume flow at higher static vacuum. Since static pressure and air speed are higher, a large hood or bracket is not required for a high vacuum system. You are closer to the source of fume generation than with ventilation by a large hood at low pressure.
With a low vacuum system, there is a high volume flow at lower static pressure. In terms of fume extraction during welding, this means that larger quantities of air have to be moved. If the air is routed out of the building, additional costs are incurred in winter and summer, since the discharged hot or cool air has to be replaced by the same amount of fresh air in the plant. Yet the air circulated back not only has to be fresh, it has to be brought to the right temperature. The costs of moving these significant air quantities are high.
More information you can find in our blog article:
Central fume extraction systems are expensive, but require relatively low maintenance for the welder.
Stationary systems are more or less maintenance-free for the welders themselves, servicing is the responsibility of the plant management. This means welders have more time for welding. Performance is reliable and stable. Central fume extraction stations almost always have a larger motor and filter, in other words the filter has to be changed less often. The fume extraction torch is simply connected to the central system and work can begin. Even if you have a large plant with more than 40 mobile welding stations, there is a system available that can accommodate these requirements. In addition, there is also less noise for the welders since the extraction system is further away.
The disadvantage of central extraction systems is that a high initial investment is required. It has to be borne in mind that these systems require a lot of upfront capital because of the electrical requirements, the work involved in getting the system up and running and the consultation required to introduce the system. The high operational costs have to be considered, too, since the circulation of large air masses consumes a considerable amount of energy in both summer and winter.
Portable and mobile fume extraction systems are handy, can be transported easily from one workstation to the next, and are less expensive both in terms of initial investment and running costs than central fume extraction systems. You can install them yourself and they can sometimes even be positioned under the workbench. There are also some systems available for the connection of several fume extraction torches. Up to two welding workstations can be served by our fume extraction system xFUME® ADVANCED.
One of the first system solutions on the market for welding fume extraction and power source combined in one unit is the xFUME® POWER 250 from ABICOR BINZEL. This mobile air-cooled combined unit has a 250 amp power source with a duty cycle of 30% and integrated welding fume extraction. It is especially suitable for thin-sheet welding with extraction at the source and – depending on the welding position – captures between 90% and 98% of the welding fumes at a welding workstation. The integrated filter in the fume extraction module filters up to 99.95% of all dusts > 0.1 µm out of the welding fumes.
Local fume extraction – also termed LEV (Local Exhaust Ventilation) – with fixed or movable extraction hoods and arms can be an easy and inexpensive introduction to fume extraction systems. A local welding fume extraction solution can provide good protection for welders’ health at just a small investment.
If the fume extraction hoods are correctly positioned and guided properly in relation to the welding position, they are highly effective and can achieve extraction values almost comparable with high vacuum systems.
Advantages of the fume extraction arm
Extraction hoods are an excellent option for beginners or as an entry-level solution on account of their low price and simple use. The solutions for local fume extraction are effective without having to make any changes to the welding process or working environment. Air quality is improved and you can keep using the same welding torches.
The arms can be used very flexibly, because there are currently no guidelines in Germany for a fixed distance between the extraction hood and the welding point. In England, on the other hand, there is a specification of 15 cm as a fixed distance from the welding piece to the extraction arm.
A special feature of welding hoods and arms is that they can also be used for other thermal processes such as plasma cutting or abrasive cutting.
Disadvantages of the fume extraction arm
Extraction arms are often used as an entry-level solution for fume extraction. For this reason, always make sure that the system you have chosen is a high-quality product that has an efficient filter.
The size of the filter in the extraction system is an important criterion. A large filter area means longer service life and less maintenance. The filter surface of the fume extraction system xFUME® FLEX from ABICOR BINZEL, for example, is three times larger compared with other hood extraction systems with extraction arm on the market.
The disadvantage of extraction systems with extraction arm is that they are only suitable for welding work or other thermal jointing processes that can be carried out directly under the extraction hood. LEV systems are not suitable for longer weld seams, for example, since the extraction arm with hood has to be moved along or readjusted during welding for proper welding fume extraction.
xFUME® FLEX: The mobile all-rounder for fume extraction
Extraction hood filters
Extraction arm systems also use filters. These have to be serviced and replaced to guarantee constant extraction and filter performance. A grid in front of the extraction hood prevents other objects from the surroundings being sucked in and thus soiling or blocking the filter.
If welding is done for many hours a day, you need a filter that can be cleaned mechanically with the aid of compressed air. Disposable filters must be checked regularly and replaced as needed.
Extraction distance & extraction capacity
The extraction capacity is decisive for the distance between an extraction hood and the welding process. Depending on the capacity, the extraction hood can be positioned further away from the process and yet still capture the welding fumes properly.
In addition, you should ensure that the fume extraction can reach the welding point properly in accordance with the specification and that you have the right filter for your process.
In practice, welders often stand between the arc and the hood and inhale the harmful fumes before they can be captured by the hood. With a large welding spot or long workpiece, the hood always has to be positioned closed to the weld seam and moved into the right position by the workers. However, welders often do not interrupt their work to keep repositioning the extraction arm when their arc moves along. In addition, constant stopping and restarting would take too much time and have a negative impact on the quality of the weld seam.
MIG/MAG fume extraction torches with extraction at the source are usually much more suitable in such cases. They are always directly at the source of the welding fumes. Extraction is part of the welding process, precisely where welding is being carried out. This way, more fumes are captured.
In manual welding, there are different solutions available for welding fume extraction. Here we will address each of the options available to you for fume extraction, as well as outline their advantages and disadvantages and what you should look for in each option.
Fume extraction torches (extraction at source)
Extraction at source – so-called extraction at the source – is expressly recommended according to the Ordinance on Hazardous Substances (GefStoffV Annex I No. 2 see DGUV information sheet “Effectively capture and separate welding fumes”: “A safe method of protecting welders and other employees in the vicinity against welding fumes is to capture these at the source. This prevents them even reaching the breathing area of the welders and the hall air. To achieve this, capture systems integrated in the torches must be used or suitable capturing elements must be positioned near the source […].”
When choosing your extraction torch, you should make sure it has three features:
- Easy and comfortable to handle, good ergonomics
- Good accessibility and view of the process
- Efficient fume extraction without impairing the shielding gas coverage
Find more tips in our blog article: Welding correctly with fume extraction torches: 3 practical tips
Ergonomics & weight of the fume extraction torch
Extraction torches for extraction at the source are not at the top of the popularity scale of welders. Due to their additional construction with an extraction nozzle and a cable assembly that is thicker on average, they appear quite unwieldy and heavy. It also makes a free view of the process more difficult. Over the past few years, progress has been made in reducing the weight and improving the handling of extraction torches in order to make them more comfortable to use and reduce the weight and strain of the extraction torches without compromising performance. Some of these improvements include ergonomic handles and swivel designs on the cable assembly for more freedom of movement for the wrist, which makes guidance of the fume extraction torch easier.
ABICOR BINZEL has launched a new extraction technology line on the market with the xFUME® range, for example. The extraction torches in this new line have a slimmer front-end than conventional extraction torches, are lighter and more ergonomic and have an optimum balance between torch neck and cable assembly. Welding with an xFUME® extraction torch feels the same as with a comparable standard welding torch.
Fume extraction torches used to be very heavy due to the weight of the cable assembly and the handle design.
Accessibility for the welder
The size of the extraction nozzle and the torch front end are of decisive importance where accessibility for the welder is concerned. If these components are too big, the view of the welding area is difficult or limited. The welder has to change posture and sometimes even “buckle over” to be able to see the weld seam. These torches are rejected accordingly. Modern torch ranges such as xFUME® PRO or xFUME® COMPACT from ABICOR BINZEL have none of these limitations.
Cable assembly & volume flow
The ability of a fume extraction torch to capture welding fumes effectively depends on a major extent to its cable assembly design. This includes the outer hose diameter and limiting the restrictions inside the hose to allow fumes to move freely from the extraction nozzle to the extraction system. When developing cable assemblies for fume extraction, flow simulation is always used, at least at ABICOR BINZEL. The advantage of this is that air flow can be visualised. By adjusting the contours, it is then possible to have it flow as laminar and turbulence-free as possible through the complete cable assembly. The extraction power of the extraction torch can be increased this way.
The volume flow through a fume extraction torch is generated by a vacuum at the rear connection of the torch. Users often debate on how much volume flow is needed. The answer to that is as much flow as possible without compromising the process – particularly the function of the shielding gas.
Welding torch consumables – why quality counts
Just as with standard manual torches, the quality of the fume extraction torch consumables is crucial for weld seam quality. The better the wear parts, the better the welding result will be. Conical parts should always be preferred, for example, due to their ease of maintenance and better accessibility. In addition, there will be less spatter build-up because the coarse thread makes adhesion more difficult and remains concentrically aligned with the contact tip holder.
Also pay attention to the material the wear parts are made of. Copper and brass, sometimes coated with chrome, silver or nickel, are all considered high-quality consumable materials. And the better the raw material is processed, the better the performance of the consumables.
Extraction nozzle design
The design and positioning of the extraction nozzle in relation to the gas nozzle is also a very important evaluation criterion for fume extraction torches. With the extraction nozzle, the torch captures the fumes and extracts them through the vacuum system. The closer the extraction nozzle is to the process, the more fumes can be absorbed. If it is too close, there is a risk of gas turbulence and the unintentional suctioning of shielding gas, which can lead to a porous weld seam. If too far away from the process, the dangerous welding fumes are not effectively extracted.
The size of the nozzle openings is another issue. Larger extraction nozzles and larger openings at an optimal distance from the welding process are very effective extraction nozzle designs for extracting welding fumes without affecting the gas coverage. It is best to ask the manufacturer of extraction torches and extraction nozzles under which aspects they have been developed. Flow simulations are methods used today for the advanced development of extraction technology.
In comparison: Standard MIG/MAG welding torches and fume extraction torches
You are welcome to carry out a comparison test to see how fumes are distributed during MIG/MAG welding. Take a normal MIG/MAG welding torch and do some welding. Then test a fume extraction torch in the same position welding the same workpiece. Try out different extraction torches if you like. Then choose the torch that extracts the welding fumes best and feels right overall. Finally, both aspects must be convenient for you: extraction performance and handling.
If you do not want to buy different fume extraction torches straight away and would like to test different extraction systems first, contact your specialist welding distributor. They know which of their suppliers offer free trial orders of extraction torches – and the matching mobile extraction systems.
At ABICOR BINZEL, we offer free trial orders. Alternatively, it is also possible to carry out test welds in our in-house Innovation and Technology Centre (ITC) to compare fume extraction torches, their handling and welding fume capture. Please contact the experts from ABICOR BINZEL directly for advice.
The position of the extraction nozzle is very important for optimum fume extraction. Too close to the process can lead to porosity. Too far away and the fumes are no longer captured.
Even with automated welding processes – especially with welding robots – health hazards caused by harmful welding fumes and associated safety hazards for affected workers can be prevented. There are several solutions for fume extraction of welding robots available to those who are looking for comprehensive solutions.
Conventional welding fume extraction applications for welding robots
Usually, fume extraction for a welding robot requires the robot cell to be enclosed – i.e. provided with an appropriate housing – and a kind of duct system is installed and to discharge the welding fumes into a collection container inside or outside the plant.
For manufacturers who weld large customised parts or need to use an overhead crane in order to lift out parts, these methods are not possible. In such cases, one fume extraction option is to filter the air in the entire plant within a circuit – using so-called central extraction and filter systems. These replace the complete air in the hall within a very short time. However, this also means that the fresh air supplied from the outside has to be heated to the required temperature in winter and cooled accordingly in summer. Therefore, the operating costs for such systems are correspondingly high. Moreover, with such a system the welding fumes still pass by the workers.
Implementing fume extraction as part of a retrofit of this scale requires not inconsiderable investment in duct systems and air filtration equipment plus a possible reorganisation of the production facility. So it’s not really surprising that not all companies can afford such a retrofit, which involves downtime and the necessary factory equipment.
Extraction at the source with welding robots
However, there are other solutions. For instance, the use of a single fume extraction unit can cover several workstations and ensure protection against welding fumes for several workers. When possible, fume extraction should be directly at the source during welding. By extracting the welding fumes immediately during the welding process, there is no possibility of the welding fumes coming into contact with workers at all.
In many production halls with welding robots, welding cells that are open at the top without welding fume extraction can be found. The disadvantages of stationary extraction systems make it clear that other solutions for welding fume extraction are needed in such cases. Such a system, which is far more reliable, is the extraction at the source system for welding robots. Using a high vacuum system, the harmful fumes are extracted directly at source.
When extraction at the source is installed on welding robots, the following must be considered:
- To make efficient use of fume extraction at a 6-axis robot, a mounting device is required which allows the cable assembly to rotate in order to avoid downtimes
- The extraction hose must be attached in an optimum position
- As with manual fume extraction, the extraction nozzle must be designed to capture the welding fumes without affecting the process
- Access to the workpiece must be guaranteed at the front end of the welding robot
Conventional robot welding torches do not have to be replaced immediately by robot extraction torches for welding fume extraction at the source. With a mounted welding fume extraction solution, the problem of hazardous fumes in the ambient air is solved quickly, efficiently and at comparatively low cost. The xFUME® ROBO extraction kit from ABICOR BINZEL offers such a possibility.
Advantages of extraction at the source with welding robots
The clear advantage for a robotic fume extraction solution at the source is that the system is a lot smaller, a lot less cumbersome and faster to implement. This allows for greater flexibility at a significantly lower cost.
With a centrally positioned fume extraction system, even several welding robots – each equipped with extraction equipment – can be connected. This method is thus perfect for reliable, easily accessible and safe extraction during MIG/MAG welding at several robot workstations and is used, for example, in general mechanical engineering, heavy engineering, construction and industrial energy applications without interfering with the welding process.
Filter cleaning & general maintenance for welding robot extraction at the source
Filters are used in the extraction systems to clean the welding fumes or collect the particles from the fumes. For welding robots, these filters should ideally be self-cleaning. In an automatic cleaning process, the pressure difference between the side with clean air and the side with polluted air is measured. If there is a difference in pressure, a pulse is triggered and the filter is blown out with compressed air for cleaning. The blown-out particles are collected in a so-called dust box or dust drawer and must be disposed of properly.
Since the automated cleaning process runs while the extraction system is in operation, there is no downtime due to filter cleaning times. In addition to automatic filter cleaning, however, there are other maintenance and cleaning tasks that need to be done manually with robotic extraction solutions. For example, the extraction nozzle and the hoses should be cleaned regularly to prevent clogging. The dust boxes or dust drawers must also be emptied regularly and the carbon brushes must not be worn out.
From the point of view of energy consumption alone, extraction at the source for welding robots is much more ecological than central hall extraction systems where large quantities of air are circulated. Furthermore, there is a clear advantage in terms of health and safety at work: The harmful fumes do not get into the environment in the first place – i.e. do not enter the respiratory systems of the other people working in a production hall.
Upgrading of a robot torch with extraction at the source
The implementation or upgrade of a robot welding torch can be realised relatively easily and quickly using an extraction kit for extraction at the source. Only the following information is required:
- Diameter of the torch neck
- Angle of the torch neck
- Length of the torch neck
- Length of the cable assembly
With a little skill, the installation can easily be carried out by an experienced welding specialist from your own company. The ABICOR BINZEL extraction kit can easily be mounted on many robot torches from other manufacturers. Sometimes only minor adjustments to the mount are required and the extraction kit is ready for use.
Mechanised welding systems are used in simple automation processes where repeatability is required, such as welding plates, beams or pipes. These systems are designed to reproduce work sequences from manual welding.
Mechanised systems require less equipment investment than robotic processes and are widely used in more open areas rather than closed cells. Examples include welding tractors for joining long components or large workpieces and stationary systems for welding small components clamped in holding fixtures.
In mechanised welding, welders adjust the equipment or torch themselves in order to control, adjust and visually monitor the welding process.
In automated welding, welders/operators are exposed to harmful welding fumes and the use of personal protective equipment is obligatory. For this reason, fume extraction is mandatory even if the environment is well ventilated.
Welding fume extraction with automatic torches in practice
Collecting fumes through extraction arms or a hood system are solutions used in processes where the torch remains in a static position or performs short movements. Where mechanised welding of longer seams is carried out, an extraction system such as the xFUME® ROBO extraction kit from ABICOR BINZEL provides more advantages. An extraction arm with hood system always has to be moved along, which is not productive in practice.
Extraction at the source systems are thus also used in mechanised processes and have greater extraction efficiency of over 90% since they are positioned directly above the welding area.
Automatic MIG welding torch fitted with integrated direct fume extraction for maximum fume capture of more than 90%
TIG welding processes produce lower amounts of visible pollutants compared to other forms of arc welding. However, these invisible welding fumes are no less harmful to health. On the contrary, they are highly carcinogenic! Stainless steels and high-alloy steels are mainly welded using the TIG process. These contain chrome (VI) compounds which can cause cancer in the respiratory system. Aluminum and aluminum alloys contain aluminum oxide which can lead to aluminum pneumoconiosis. Damaged parts of the lung then just simply stop working.
In addition, large amounts of ozone and nitrogen oxide are produced during TIG welding, both of which are considered irritant gases and are thus especially hazardous. Ozone is mainly produced during the TIG welding of stainless steel and aluminum and causes in particular dryness and scratchiness in the throat, coughing and a feeling of tightness in the chest.
The metals welded using the TIG process therefore generate extremely harmful fume particles that must be captured using a specially designed extraction system. These extraction systems must contain filters of fume class W3, which can also capture the fume particles from alloyed steel with alloyed components such as chrome and nickel (high alloy steel with x ≥ 30 % nickel-based alloys). Filters of this performance class are marked »W3«.
This performance is provided by the fume extraction systems xFUME® ADVANCED W3, FES-200 W3 and FEC W3 from ABICOR BINZEL, for example. Together with the xFUME® TIG extraction torch for extraction at the source, they form ideally matched fume extraction system solutions.
Regulations and guidelines governing welding fume extraction
In Germany, you can download the current technical rules for hazardous substances in welding from the Federal Institute for Occupational Safety and Health.
Annex I No. 2 “Particulate hazardous substances” states:
“Dusts must be captured as completely as possible at the points of emission or creation and disposed of safely. The exhausted air must be ducted in such a way that as little dust as possible enters the breathing air of workers. The exhausted air may be returned to the work area only once it has been adequately purified.”
This means that when fume extraction systems of the separation classes W2 and W3 are used, the captured and filtered air may be returned to the working environment.
The currently applicable welding fume regulations TRGS 528 and DGUV rule 109-002 were updated according to the latest findings at the beginning of 2020. These were incorporated in the Technical Rules for Hazardous Substances (TRGS) 528 “Welding Work”. They also serve as a benchmark for employers’ liability insurance associations, which visit production plants in regular cycles and check the current conditions on site. The inspection includes ventilation, constructional and substitutional measures, fume extraction at the source, air recirculation and all organisational and personal protective measures during welding.
Companies are obliged to comply with the regulations for welding work. If the regulations are violated, the employers’ liability insurance association can shut down production until the deficiencies have been remedied. There is no need to explain in detail here what this means for a production company.
While it is argued that fume extraction torches provide a “lower performance”, the answer is a resounding “no” – you won’t sacrifice any performance.
Today’s fume extraction welding torches perform just as well as regular welding torches with capacities from 200 to 500 amp air cooled and liquid cooled for almost every possible application that a standard MIG torch can handle.
The welding torches also feature the same range of functions as a standard MIG torch.
It’s no problem to configure extraction torches for industrial welding devices. If your welding device has an Euro central connection, torches can be connected using suitable cable assemblies or adapter solutions. A fume extraction torch and an extraction system must be connected in addition to the power source. There are suitable adapters or connection hoses available for different hose diameters.
The durability of the outer hose varies. It is made of a special material that is resistant to heat and UV rays. It might have to be replaced regularly like all cable assembly components, but it is suitable for the normal industrial environment. There are special covers available which provide extra protection for the outer hose.
With fume extraction torches, there is a risk that improper handling may jeopardise optimum shielding gas coverage, resulting in the formation of pores. Reworking is very expensive. However, if you consider a few things, you will have good shielding gas coverage and effective fume extraction.
You should make sure that the extraction volume flow does not reach the shielding gas zone. If you measure turbulence near the end of the shielding gas nozzle, your extraction flow is too powerful or the shroud is too close to the welding process.
This was a common issue with the first generation of fume extraction torches. In order to fit all the additional components into the first fume extraction torches there was a significant amount of added weight that made the torch bulky, heavy and cumbersome to handle.
Today, with a much increased focus on weight reduction, welder access and ergonomics, modern fume extraction torches are far more comfortable and welder-friendly tools. So much so that some – including our own ABICOR BINZEL fume extraction torches – actually weigh less than comparably rated welding torches without fume extraction.
weld.com has a great YouTube video that covers the fume extraction weight question.
There are fume extraction torches that are heavy and bulky to handle, which can affect welders’ stamina. But even the strain of using a fume extraction torch would depend on the torch you’re changing from and the extraction torch you have chosen, because there are fume extraction torches available that achieve the same feel and handle as most MIG torches on the market.
It also depends on the position your welders have to work in. Of course, overhead positions and vertical welds are more straining than horizontal or down welds, so heavier fume extraction torches could be more strenuous and adversely affect extraction performance because if the torch isn’t positioned properly it won’t capture the fume as much as it could. Try a fume extraction torch for yourself and see if it makes a difference.
You can find plenty of MIG torches with a ball joint at the connection of the cable assembly and there are plenty of cable assemblies available that weigh the same as many MIG torches without fume extraction. Do some research and talk to your welding equipment supplier or a qualified representative.
The only additional consumable a fume extraction torch requires is the extraction nozzle. Apart from that, you’re using the same set-up as for a regular MIG welding torch: gas diffuser, tip holder, contact tip and gas nozzle.
In brief: no. Fume extraction torches handle any wire – whether filler wire, metal core or solid wire. However, depending on the wire used more fumes can be produced. When welding with metal core and solid wire electrodes, you are likely to go to higher amperages and hotter gas mixtures, which results in more welding fume being produced and spreading faster, making the welding position more difficult for fume extraction at the source.
Metal core wire: Some welders believe that welding metal core wire with a clean gas mix (i.e. CO2) produces “clean” fumes which do not have to be extracted. This is a common myth. Toxic particles are still released to the atmosphere as the base metal melts. Without suitable extraction systems and procedures, your welders and other workers nearby will breathe these in.
Flux cored wire produces very thick and visible fumes during welding. It also releases a lot of particles into the atmosphere which should be extracted at the source. Flux cored wire is also generally used for low current welding, which makes it very easy to extract at the source.
The service life of filters in fume extraction systems is difficult to predict. Systems with a cleaning mechanism will generally last between 3 and 12 months. For systems with no automatic cleaning process, it’s very dependent on the filter size, the welding wire used, base metal and the parameters of the welding equipment.
On LEV systems the filter is usually not monitored automatically, i.e. there is no signal whether the filter is full or not. How long the filter lasts depends on the duty cycle, the welding process, the material welded, etc. and it is difficult to specify a filter change interval. For our fume extraction systems, we say that if they’re being used 3 to 4 hours a day, the main filter cartridge has a minimum service life of at least 4 weeks to 12 months.
Regardless of this, it is important to monitor the efficiency of the fume extraction system. If you have the impression that this is inadequate, the filter is one of the first things to check. Some systems have built-in sensors or gauges which indicate when the differential pressure in the filter is too high.
Every fume extraction arm should be in the volume flow range of 1,000–1,200 m³/h. This value is lower for some arms. These systems ideally have a higher volume flow and a lower static pressure compared to solutions that are combined with fume extraction torches. Please note that the volume flow is the main performance parameter for fume extraction systems.
Portable fume extraction systems are evaluated more according to static pressure than volume flow. The typical range for a mobile fume extraction system is 102–170 m³/h.
Since the welding torch is usually a very restricted tool, you need a system that generates enough static pressure to overcome these restrictions.
Yes, some systems offer adjustable extraction regulation (min./max.). The fume extraction system xFUME® ADVANCED, for example, has an adjustable volume flow regulation. Ask your welding distributor or manufacturer if such fume extraction solutions are available.
The flow quantity can be adjusted quite simply on the xFUME® ADVANCED, for example, using the “Air Flow” rotary knob.
A safe and healthy working environment for welders is not only mandatory, it should be at the top of your list of priorities out of personal interest. We assume that the limit values will be adjusted further downwards to ensure health protection in the workplace.
There are already numerous fume extraction options on the market and there are many ways to optimise fume extraction in your company – no matter how many welding stations you have or how much money you can invest. If you are unsure, ask your welding distributor to review your options or ask for a demonstration. It’s easiest to determine on site which extraction technology solution is best suited for your applications.
We hope that you enjoyed this e-book and that your expectations have been fulfilled.
Your suggestions and comments are always welcome.
The following people contributed to this eBook:
Alexander Binzel Schweisstechnik GmbH & Co. KG, Germany
- André Faber, Head of Extraction Technology
- Florian George, Product Manager Extraction Technology
- Herbert Burbach, Art Director
- Carmen Laux, Marketing
- Christine Rinn, Marketing
- Stefan Schneider, Marketing