Within just three weeks, the existing system for handling chips and cutting oil was completely modernized, automated and all systems - whether old or new - were networked via the new control system. "The existing system was dismantled in just two days, after which we started setting up the new system," recalls project manager Markus Otto from Kabelschlepp. "After just under three weeks, Voswinkel was back in production. "To ensure that the work was carried out as smoothly as possible, the project was planned well in advance - in close cooperation between the client and contractor.

Old becomes new - where necessary

The first step was to define the extent to which the existing system needed to be replaced. "We didn't want to simply replace everything completely, but rather carefully adapt the old system to the new requirements. We wanted to keep the effort as low as possible," explains Thomas Stein, Industrial Engineer at Voswinkel. "Kabelschlepp understood this briefing and had already made good and pragmatic suggestions during the tendering phase." This fact also tipped the scales in favor of awarding the project to the company. "We had had good experiences with their sponsors and were confident that Kabelschlepp would also be able to support us well in plant construction," says Stein. "It was important to us that we received everything from a single source - the coordination with other suppliers was also to be handled entirely by Kabelschlepp." In addition to several new conveyors, Voswinkel also decided to invest in a new belt filter system.

Removal of chips and cleaning of cutting oil

While interlinked conveyors transport a large proportion of the chips to a central container, the contaminated cutting oil first collects in a scraper conveyor. "This scraper conveyor is a central link in the overall concept; it runs in cycles to ensure sedimentation and to carry as little cutting oil as possible during conveying. In addition, the cutting oil is pre-filtered here and pumped to the central belt filter system via an integrated lifting station, where we achieve a purity level of 25 µm and a throughput rate of around 250 liters per minute," explains Markus Otto. In the disposal concept, all chips are also fed through a centrifuge, which removes as much adhering oil as possible. The centrifuged chips are then conveyed into the appropriate chip containers. The low residual moisture allows for more economical recycling.

Making everyday work easier

The 33 machines are supplied from a storage tank via a ring line, which provides the required amount of cutting oil to each individual machine depending on the pressure. If the preset pressure level drops - for example due to a machine's increased cutting oil requirement - the delivery volume is adjusted. The entire process is controlled centrally via the new control system and runs fully automatically.

The points described above are just a few examples of the fully automated, centrally controlled processes that represent the main advantage of the new system for Voswinkel. "The time required to operate and maintain the system has been significantly reduced since we have been able to monitor and control all components via the central terminal," explains Stein. "One concrete example: We no longer have to open lids to check fill levels. This alone has made our day-to-day work much easier." The Industrial Engineer's expectations of the new system have been met across the board. At the same time, Thomas Stein is still impressed by how smoothly the complex modernization project went: "The schedule was adhered to very well, even though plans changed during the conversion and ad hoc solutions had to be found for smaller, unforeseeable problems. Kabelschlepp always reacted flexibly and handed over a turnkey system on time, which we are still very satisfied with."

Uwe Becher, Senior Manager Sales, Caps Division, Tsubaki Kabelschlepp / am