Surface World July 2020 Handbook | Page 142

ACP SYSTEMS AG Optimum preparation of bonding sites with CO2 snow Cleaning structural joining surfaces effectively and efficiently In order to save weight, an increasing number of assemblies used in the automotive industry today are made of plastic or lightweight metal which need to be glued together. The reliable pretreatment of the joining surfaces is a must, especially where structural components are concerned. This is where quattroClean comes into play. The climate-neutral technology has a number of advantages over other dry cleaning processes. Lightweight construction is not new to the automotive industry. However, as electromobility is becoming more popular and CO2 emissions continue to be reduced, this topic is becoming increasingly relevant. OEMs and suppliers are therefore turning to lighter materials such as aluminum and plastics for body parts, e.g. doors, vehicle roofs, trunk lids, tailgates and engine hoods. Changes in manufacturing and joining methods such as bonding instead of welding, riveting or screwing, enable further weight savings. To guarantee the necessary adhesive strength when bonding structural body parts or battery housings, for example, the joining surfaces must meet high cleanliness and wettability requirements. Efficient partial dry cleaning instead of full-surface wet cleaning For various reasons, conventional wet-chemical cleaning processes with water-based media or solvents are not suitable for this. Among others, the areas to be joined invariably have to be much cleaner than the rest of the component. When it comes to the selective cleaning of structural joining surfaces, such as body parts or battery housings, the robust, cold and dry quattroClean process with its wide working window ensures that cleanliness requirements are met. Such cleaning processes cannot be integrated into a production or assembly line - or can only be integrated with extreme effort. Consequently, dry processes are preferable, for example the environmentally-friendly quattroClean snow jet cleaning technology from acp systems AG. It is implemented in a wide range of industries for the selective or full-surface cleaning of components made from practically all types of material. The cleaning process is so gentle on materials that even delicate substrates can be treated. The cleaning medium used by the technology is liquid carbon dioxide, which is generated as a by-product from chemical processes and energy generation from biogas and therefore environmentally neutral. It is guided through a wear-free two-component ring nozzle and expands on exiting to form fine CO2 snow. This core jet is then bundled by a separate jacketed jet of compressed air and accelerated to supersonic speed. When the easily-focused jet of snow and compressed air impacts on the surface to be CONTINUED ON PAGE 142 140 2020 - 2021 read online: www.surfaceworld.com