KWM Weisshaar is committed to providing its customers with a reliable supply of goods. That is why the sheet metal specialist relies on dependable storage solutions from KASTO. The latest retrofit of the KASTO UNIGRIP buffer storage system demonstrates that this was the right decision. After a brief reconfiguration, the system is now operating smoothly, ensuring the high level of process reliability that KWM Weisshaar has come to expect.

2007 – the German national women's soccer team won the World Cup and Apple presented its first iPhone. In the same year, KWM Karl Weisshaar Ing. GmbH expanded and constructed a new multi-story production hall at its headquarters in Mosbach, Baden. “We reorganised our entire material flow and invested in modern production machinery and efficient warehousing technology,” recalls Jörg Weisshaar, who holds a degree is in industrial engineering. As the second generation, he manages the company together with his father Karl.

KWM, as an all-rounder, offers a complete sheet metal process chain, providing everything from engineering to sheet metal processing, joining and welding, assembly, and logistics, all from a single source. In addition to processing steel, the company also handles stainless steel and aluminium, totaling around 5,000 tons per year. Karl Weisshaar established the company in 1979. During its early stages, the company provided products such as computer housings to the PC and printer manufacturer Hewlett Packard. “A significant milestone for us was the development of laser technology. This technology enables precise cutting of sheet metal, which has made the material so popular to this day,” explains Jörg Weisshaar.

The company has an annual turnover of about 50 million euros and employs around 450 people, with approximately ten percent being apprentices. The primary market is the DACH region (Germany, Austria, and Switzerland), with the most significant industry being rail vehicle construction. The company not only manufactures mechanical components such as roof segments for railcar bodies, but also complete air conditioning units and battery boxes.

Comprehensive solution

In 2007, KWM was seeking a manufacturer who could supply not only the order picking storage system for the final assembly, but also the depot for raw materials for its production hall. "Working with the same partner for both storage systems was key for us", recalls Jörg Weisshaar. Another factor for the company played a significant role in the decision process: "The supplier needed to be able to implement the project quickly because we were completely reorganising our material flow while the operation was ongoing." Karl Weisshaar discovered KASTO while attending a trade show and was impressed by the company's offerings. "We requested quotations from other companies, but KASTO ticked all the boxes,” emphasises Jörg Weisshaar. The proximity was also an added advantage, since both companies are based in Baden-Württemberg.

The sheet metal all-rounder has been using a KASTO UNILINE with 13 output stations for raw materials and a KASTO UNIGRIP with three output stations as buffer storage for semi-finished products for 17 years. The UNIGRIP 3.0 features 682 spaces that can accommodate mesh boxes in various sizes – ranging from 530 to 2,000 millimetres in height. Each cassette has a maximum payload of three tons. The output stations are equipped with sensors that monitor the dimensions of the load on the plates and stop operation if the specifications are exceeded.

“Throughout the years, we encountered only very few storage system-related issues,” said Holger Guddat, in charge of maintenance and repair at KWM. “The technology operates flawlessly, which is crucial to us, since any downtime would stop the entire production process." With this in mind, the company ensures that its storage systems are regularly serviced. “And if the unexpected occurs, we can rely on KASTO for prompt assistance,” the maintenance manager reports. "When we report a fault, a service technician usually comes by the same day. Malfunctions were rectified almost always within a few hours."

Remaining a reliable supplier

So why carry out the retrofit now? “KASTO informed us that they would no longer be able to guarantee the complete and, in particular, timely supply of spare parts for the 17-year-old electronic components in the future,” said Holger Guddat. "That could result in supply delays for the components we need, which would hinder our manufacturing process. This is unacceptable to us," says Jörg Weisshaar. He adds, "Our customers rely on just-in-time methods, such as Kanban or consignment warehouses. Our customers depend on us to deliver the components they need at the right time, no matter the situation. Because many products are not fully assembled until the buyer requests them, we must maintain buffer storage at all times with the semi-finished products ready for use.

Thus, the main requirement for the retrofit was defined: "It must be completed quickly, with minimal impact on production. Therefore, the project started at the turn of the year 2023/2024,” reports Holger Guddat. KWM prepared everything using its in-house personnel. This included, for instance, integrating the large switch cabinet of the overhead gantry crane (OGC) into the storage system. "The cabinet was too large for a person to access. Our solution was a scissors lift that we brought into the storage system and one of the output stations that we used to remove the old switch cabinet and move in the new one."

Like clockwork

On January 2, 2024, the real work began. Ten KASTO service technicians replaced all the electrical components. They replaced the switch cabinets, including all control units, replaced the station control panels, converted the bus technology to PROFINET, upgraded the energy supply to the OGC and the lifting beam, and updated all drive controllers. They modified the safety equipment and devices, such as the limit switches for the hoisting gear and longitudinal travel, emergency stop system, safety door, and light barriers to meet current specifications. In addition, the warehouse management system (WMS) KASTOlvr was upgraded to KASTOlogic. Furthermore, they revised the documentation. "A lot of work needed to be done, but after seven workdays, they completed it according to schedule," says Holger Guddat, expressing his respect. During the following three-day commissioning, KASTO personnel trained KWM employees on using the new technology. The storage system is now fully operational again in two-shift operation. KASTOlogic can be interfaced with the proALPHA ERP system to ensure seamless data transfer.

Both Jörg Weisshaar and Holger Guddat agree that "our experience with the retrofit has proven very positive." "The project was well-organized, and KASTO did an excellent job of implementation. With UNIGRIP, we are once again well equipped for the next 17 years.” With this in mind, both are looking ahead to the next turn of the year with confidence. "On January 2, 2025, we will begin the next retrofit project with KASTO – this time with our UNILINE.”