Metabo, a manufacturer of power tools for professional users, invested in a new automated warehouse to supply production in 1995 in order to create capacity for further growth. With success: today the company has a turnover of almost 500 million euros. The warehouse reliably supplies the assembly department with components and raw materials. Nevertheless, after 24 years, it was no longer completely reliable, as Dennis Bosch, Head of Logistics at the main plant, explains: "Although we had already modernized the material flow computer in 2005, the number of faults increased over the years, even if they did not yet get out of hand." Metabo wanted to avoid the risk of downtime, as the warehouse must always be available - production is structured in such a way that replenishment must be at the installation site after a maximum of four hours. "viastore regularly reminded us that outdated components in our system pose a risk to availability," explains Bosch.

System analysis as the basis
In 2018, the company decided to carry out a comprehensive retrofit. "viastore comprehensively analyzed the condition of the system," says Dennis Bosch. The experts examine the condition of every component. This can take three weeks, but the effort is worth it: "This allows us to work out the risks very clearly and derive actions. We also draw up proposals for reorganization, as processes often change over the years," explains Lars Breuer, Deputy Head of Retrofit at viastore. "Many components had been discontinued. Spare parts were no longer available for the old control systems in the conveyor technology and storage and retrieval machines." The IT hardware was also outdated.

Focus on the customer: Dennis Bosch, Head of Logistics at Metabo's main plant, left Gregor Rentschler, Project Manager Retrofit at viastore, right Lars Breuer, Deputy Head of Retrofit at viastore. © viastore

Precise preliminary planning based on a detailed roadmap
"The preparatory work was not without its challenges," recalls Dennis Bosch. "We had to move the items that were needed in production during the modernization period to other locations in the plant." To enable Metabo to plan this, viastore recorded in detail in a roadmap which work would be carried out and when. "It was impressive that viastore adhered to the roadmap almost 100 percent," emphasizes Dennis Bosch. In the three weeks before Easter 2019, the logistics system was modernized from the ground up: The S5 controllers were replaced with modern S7s, and the transfer car - which connects the retrieval aisles of the storage and retrieval machines (SRMs) with the picking stations - was given a new drive. The controls and drives of the three fire protection doors, which separate the racking area from the rest of the hall in the event of a fire, were also modernized. "We implemented a free movement control system here, including an emergency power supply," explains viastore project manager Gregor Rentschler, "this ensures that in the event of a fire, the conveyor line at the doors is released and they can close safely." This is an aspect that fire protection insurers demand today.
The material flow computer is no longer hardware, but runs on a virtual server. The visualization system has also been updated, as have the storage and retrieval machines and the conveyor technology. The S7 control system for the conveyor technology is now connected to higher-level systems via Ethernet, so that remote maintenance of the system is now possible down to each individual component.

Replacing the stacker cranes increased performance by 30 percent
The most visually spectacular measure was the replacement of the old storage and retrieval machines. "We knew that our transfer car had performance reserves," explains Dennis Bosch. "That's why we also wanted to increase the performance of the SRMs with the retrofit." viastore calculated the performance gain Metabo would have with the current models compared to modernization and how high the additional costs would be. "With new, more dynamic SRMs, we achieve 30 percent more performance," explains Lars Breuer. The decision was easy. The two old devices were removed through roof hatches and the new SRMs were installed in the same way.

Functioning teamwork
The company fire department took care of securing the roof. "This joint management of the project with the Metabo employees made the work special," emphasizes Gregor Rentschler. "It's important that the interaction between our specialists and the customer's employees works in a project like this." Dennis Bosch confirms that "the team was an important key to implementing the overall project so successfully." Although the modernized system has only been in operation for a few months, successes are already evident: "It's still too early to give specific figures," reports Dennis Bosch. "I assume that the increase in performance will be in the double-digit range." The system runs faster, the goods are out more quickly and the data records are available immediately. Events can be quickly rectified online via remote maintenance. Energy consumption is also reduced, as the new stacker cranes use a DC link to balance motor and generator loads internally.