Regardless of industry, manufacturers that depend on high volume welding production agree on one thing: weld fumes are bad news.

The toxic elements in weld smoke threaten employee health. When inhaled, weld fumes may cause upper respiratory ailments and greatly increase the risk of serious diseases including COPD and cancer. 

Weld fumes produce some of the most dangerous airborne contaminants found in manufacturing facilities today. The high temperatures needed for welding create fumes containing exceedingly small particulates. While most of these particulates come from the weld wire, some are from the base materials. Particulates from base metals such as manganese and hexavalent chromium are extremely toxic and very dangerous when inhaled.

“Customization is important, particularly for tank manufacturing and other industries where clearing the air poses some special challenges”

Manganese is a trace element found in many kinds of welding. Breathing its particulates can cause “manganism”, a neurological condition similar to Parkinson’s disease. Hexavalent chromium is found in fumes coming from welded metals that include chromium, such as stainless steel. These particulates can be highly irritating to the eyes, nose and throat. Hexavalent chromium is also a known carcinogen. Light metals in weld fumes, such as beryllium and aluminum, can also cause health problems when inhaled, including the risk of lung cancer.

Every manufacturer that utilizes high volume welding is vulnerable to the dangers of weld fumes. Fume mitigation and air quality control are a necessity. Fortunately, today’s air filtration systems are powerful, efficient and customizable for any welding environment.  Customization is important, particularly for tank manufacturing and other industries where clearing the air poses some special challenges. The key is finding the best solution for a specific welding application.

1

Source: RoboVent

Weld fumes are pushed away from the welder and pulled into the ductwork hanging above the operator performing exterior welds on a large tank

Ambient air capture provides total-plant solution

Tank manufacturers fabricate storage tanks, cylinders and pressure vessels for many industries including oil and gas, transportation, food and beverage, and chemicals. Every industry has its own requirements, and while the volume and composition of weld fumes depends on the material and processes used, toxic elements such as hexavalent chromium, manganese, nickel and beryllium are often present.

Storage tanks for the oil and gas industry, for example, are massive weldments. They are too large to be contained under a fume hood and may require the use of overhead cranes. As a result, capturing weld fumes at their source, which is usually the most economical and effective method of air quality control, presents an extremely difficult challenge. Also, large storage tanks, valves and other components are often made of stainless steel which produces especially toxic weld fumes including hexavalent chromium. In this situation, one of the more common solutions for protecting welders and anyone else working in the vicinity of the work is ambient air capture and filtration combined perhaps with some Powered Air Purifying Respirators (PAPRs). Ambient systems will not immediately remove the fumes from the breathing zone as a source capture, backdraft-type design could.

While effective at clearing the air in a facility and reducing the overall particles in the air, ambient solutions clean the air in the general vicinity of the welding operation. There are typically three types of configurations that are used most widely: 1) A ducted push-pull system; 2) A ductless floor system, and/or 3) A ductless ceiling/wall-mounted system.

Each have their own distinct advantages. A ducted push-pull system is the most traditional method. Ductwork is installed down one side of the room or space being addressed. Collection points installed in the ductwork at regular intervals where the fume stratifies carry the particulates to a filtration unit. Clean air is then pushed in through ductwork and registers on the other side of the room creating a laminar air flow pattern across the space. A ducted system uses centralized collectors which help save space. The filtration unit can even sit outside the building.

Manual-Welding-Ambient-Vista360_Welder-Spark_2017_04_09_Tru_Form025_RGB PP

Source: RoboVent

Ambient units like the Vista360 can be mounted to the ceiling or hung from trusses in order to maximize floorspace for production capacity

In comparison, a ductless push-pull system positions a standalone filtration unit – or array of units – near welding stations and collects fumes. The unit then returns cleaned air through strong jets back into the facility. These filtration units are easy to install and can be moved around if needed. The Spire360, the Fusion Vortex and Vista360 are all examples of free-standing ductless dust collectors. The Spire sits on the floor and is placed strategically near key collection points and the Fusion and Vista can be suspended from the ceiling or wall mounted around the process to create an effective air flow pattern.

Ambient filtration systems provide total-plant solution for indoor ambient air quality. When source capture isn’t possible due to large custom components or overhead cranes, these systems can clean and recirculate the air in the entire plant without conflicting with these obstructions. By filtering and recirculating clean air, ambient systems also help avoid the costly energy bills associated with replacing the warm air that other systems simply exhaust from the building. These filtration solutions are both environmentally responsible and cost effective. No ductwork is required for free-standing, ductless filtration equipment which eliminates interference with overhead cranes or other obstructions while lowering installation cost as well..

Source capture safely extracts weld fumes in confined spaces

The most effective capture method for weld fumes is source capture filtration. If a process is automated or can be placed under or near a hood, a source capture solution is ideal – especially for welds happening on the exterior of the tank. Fabricating large storage tanks often requires manual welding inside enclosed spaces. Weld fumes can rapidly collect to dangerous levels in these conditions, greatly increasing the risk of toxic exposure. Weld smoke haze also accumulates quickly in confined spaces, affecting productivity and work quality. Fortunately, source capture – collecting fumes at the point of welding – is a proven way to reduce weld fumes where it is needed most. Welding guns with integrated fume extraction at the tip, such as the RoboVent Extractor™, provide a versatile solution for welding in confined spaces.

Combining these guns with a type of hi-vac extraction unit has proven to be an effective solution for capturing welding fumes generated at the source and help reduce the welder’s exposure to the fumes by up to 95%. The gun can be connected to a centrally placed extraction system, such as standalone hi-vac collection systems or to more portable fume extraction systems, like the MiniCube™. With this type of flexibility, the Extractor can be used in many different work environments including large tanks.

Today, tank manufacturers have many fume extraction and air filtration options for their welding operations. Selecting the right solution for their specific applications will ensure a constant flow of clean, breathable air throughout their facility.

About the author

Adam Pfeiffer, Field Solutions Director for RoboVent, has been in welding and fume extraction industry for nearly 20 years and has designed hundreds of solutions for manufacturers in the US.