What are the key differences between low vacuum and high vacuum fume control systems, and what are their respective benefits?
Why Is Welding Fume Extraction Necessary?
The fumes created by welding processes consist of solid particulates, which are formed when metallic vapors condense. Many of these particulates contain elements that are known to cause lung disease – aluminum, iron, and titanium, for example – or pulmonary irritation and/or systemic poisoning (among them copper, lead, manganese, nickel, and zinc). Fumes can also be produced from coatings and residue on the base metal, or from cutting processes such as plasma cutting or laser cutting.
The welder’s proximity to the fume source makes him or her particularly vulnerable to fume exposure. However, fugitive emissions may affect other personnel as well. Effective source-capture welding fume extraction significantly reduces particulates from entering and spreading throughout the atmosphere. This can be achieved through low vacuum or high vacuum fume extraction.
The Benefits of Low Vacuum Fume Extraction
Extraction arms are often used for low vacuum fume extraction purposes. They remove high volumes of air at a low speed, similar to the range hood of a household stove. Many industrial processes, such as welding or cutting, create a hot fume that rises naturally. The extraction arm hood can be mounted above the welding station, or placed across the welding table from the welder, with the hood or nozzle facing the fume source horizontally. The distance between the source and the extraction point allows for more working space for the welder.
Another benefit of low vacuum fume control systems is that they work with existing welding tools that are not (or cannot be) equipped with on-tool extraction systems. Backdraft tables, downdraft tables and ventilation hoods are sometimes also used to draw hazardous fumes away from the welder, but require large fans and thus more energy than extraction arms.
The Benefits of High Vacuum Fume Extraction
High vacuum fume control systems are often used to capture heavier particles at high speed, typical of various kinds of dust (and industrial processes such as grinding or sanding). But high vacuum is also highly useful for capturing fume emissions from welding, not least since extraction arms cannot always get close enough to the desired capture point. An on-tool extraction system will be able to capture the fumes right at the source on the welding torch – through on-torch fume extraction – preventing the toxic air from reaching the welder’s breathing zone. High vacuum also has the added advantage of not relying on the welder to constantly reposition a hood, thereby allowing greater freedom and productivity.
Another advantage that high vacuum has over low vacuum is that it can also be used as a general housekeeping system in the factory or workshop. Welders can weld and capture the fume, grind with a vacuum-ready grinder and capture the dust, and then clean up the workstation with standard vacuum nozzles and cleaning accessories.
Why Source-Capture Fume Extraction?
Capturing welding fume particulates at the source, whether through low vacuum or high vacuum extraction, has several benefits:
- Fume control systems with smaller capture points use smaller fans, resulting in lower up-front costs. Lower air volume movement also means lower heating and air conditioning costs.
- Source-capture extraction can eliminate welding fume exposure for welders and other factory/workshop personnel, providing a safer and healthier workplace.
- Source-capture extraction can also eliminate the amount of dust settling on surfaces and inside machinery. It will facilitate housekeeping routines, require less cleaning and maintenance, and extends the service life of the machinery.
Which Fume Control System Should I Choose?
Determining whether to go with a low vacuum fume control system or a high vacuum fume control system basically boils down to two key factors: installation space and what your welding process looks like.
- How much ceiling space do you have? Low vacuum extraction arms need 3-4 feet of clearance in addition to the mounting height.
- How much working space do you have? Low vacuum extraction arms can be anywhere between 3 and 16 feet in length. Bending a long extraction arm may restrict its airflow.
- Does your welding process move around? If yes, on-torch fume extraction would likely be the most beneficial option.
- Do you have a dedicated welding space? If yes, does it already contain several welding torches (which could then, ideally, be equipped with on-torch fume extraction systems)?
To find out more about our fume control systems, and how we can help your business maintain clean air in your factory or workshop, please contact your local Nederman office. You can read more about our work, our products, and our services at our Knowledge Center.