A healthier working environment thanks to spatial welding fume extraction

CSM produces high-quality steel structures in both areas of the municipality of Hament-Achel in Belgium, located close to the Dutch border. The company was founded in 1964 and has since evolved to become one of the most important companies in the engineering, fabrication, conservation and assembly of steel structures. CSM is a specialist in ‘difficult’ structures, often having to work with heavy parts involving tricky welding owing either to the shape of the structures or the stringent safety or quality requirements placed upon them.

The large structures produced are often many meters in length or height.
The structures are primarily used in architecture, amusement parks and in the petrochemicals industry. The company handles the entire process from price calculations through to assembly. The vast majority of the structures that it produces stay in Belgium or find their way to the Netherlands or other neighbouring countries, but its roller coasters go around the world. The Python at Efteling in the Netherlands is one of the unusual creations by the company. CSM is part of the B-steel group.

The challenge

CSM operates four production halls, accommodating a total of 30 welders and 26 assemblers working on large-scale workpieces. Welding is mostly on steel (filled 1.2 mm). This process is known for the harmful fumes that it releases, which can ultimately be the cause of a range of health conditions. As such, legislation is in place that stipulates that fumes must be extracted, captured and removed. CSM prioritises the working environment of its employees and had been operating a number of mobile source extractors.

Due to the nature of the work and structures, which are often many metres in length or height and with multiple bends, the mobile source extractors were insufficient. The welders were suffering as a result, causing them to work less efficiently and it quickly became clear that a spatial extraction system would be a more effective solution.

The solution

Before Plymovent began installing a total of six Diluter systems in production halls one and two (hall dimensions 54 x 20 x 6 m) in May 2017, it made a number of detailed reference visits to similar companies that were already using the system. After successful installation in production halls one and two, eight additional Diluter systems were added in halls three and four (hall dimensions 94 x 30 x 8) in December 2017.

The company is now operating fourteen Diluter systems in diagonal configuration.
The heat from welding causes the fumes to rise upwards in the hall where, 2⁄3 to 3/4 of the way up, they come to rest in a ‘welding blanket’. The Diluter systems are set up in the welding blanket, at around five metres high. The rising, contaminated air is extracted, filtered and blown back into the workplace in different directions as clean air through six discharge nozzles. The nozzles can be individually rotated to optimise the air flows and efficiency.

This helps to create a closed air circulation system without the need for overhead pipework that would get in the way of the travelling gantries. The filters are cleaned with compressed air in the cleaning cycle if they become too contaminated. Dust and particulate are collected in a large container for removal. The filters need to be replaced only once annually.

The Diluter systems are designed with a central control system that is operated via touch screen.
This ensures a straightforward operation from both a central location and from the devices in the workplace. The touch screen displays a floor plan of the four production halls, indicating the locations of the fourteen Diluter systems for intuitive monitoring of the status of each device and for easy operation: status on or off, number of impulses emitted, current cleaning cycle status, how long the filter cartridge has been in place, whether or not a filter needs to be replaced. The central control system allows for adjustment of an entire production hall as one or of each device individually.

In addition to the Diluter systems, a number of existing roof fans have also been used to prevent the thickening of gases.

Main benefits