While primarily associated with German engineering prowess, BMW is also, perhaps surprisingly, the largest automotive exporter of vehicles from the USA. BMW Manufacturing in Spartanburg, South Carolina, which is celebrating its 30th anniversary in 2024, assembles more than 1,500 vehicles per day, running on two shifts, and in 2023 exported cars with a value of $9.6 billion to 120 countries.
Robot Army
Central to the Spartanburg operation are its two paint shops, which employ 240 of the army of 2,600 highly efficient robots that are working alongside human co-workers at the plant.
These provide each car body with five coats of paint and two protective corrosion coatings in a process which takes 12 hours, during which time the vehicle has travelled a distance of around four miles. The entire process adds just 20 pounds of weight to the body – a thickness of 120 microns, which is the equivalent to the width of five human hairs.
Filtration systems in BMW’s automotive spray booths worldwide are crucial to ensuring high-quality surface finishes, as well as protecting worker health and maintaining environmental standards.
Designed to remove contaminants from the air within the booth, prevent dust, overspray and other particles from affecting the painting process, the technology behind these systems continues to evolve to meet ever more stringent industry requirements and environmental regulations.
Pre-Filters
Primarily based on glass or polyester media, pre-filters are the first line of defense in a spray booth filtration system, capturing larger particles such as dust and debris before the air enters the booth, in order to extend the life of the primary filters by preventing them from becoming clogged too easily.
At BMW’s plant in Leipzig, Germany, for example, specialists from Freudenberg Filtration Technologies – a long-time supplier to the auto maker – identified the greatest savings potential in the pre-filter area. Here, existing filter elements showed excessive pressure drop in comparison to their separation rate, resulting in a high level of energy consumption. These were replaced with Viledon WinAir 45 pocket filters designed for dealing with coarse dust at very low pressure drop. Test series and service life tests have subsequently demonstrated a noticeable increase in efficiency, enabling BMW to save 700 MWh a year, corresponding to a CO2 reduction of around 365 tons.