The firm was started as a forge and blacksmith's workshop in 1901 by the great-grandfather of the current managing partner, Harald Keller, who joined the company in 2001 and has overseen a rapid progression towards the supply of sheet metal parts and assemblies to customers in such diverse industries as automotive, food production, medical, pharmaceutical, solar and general mechanical engineering.

The customer base continually presents challenges due to the wide range of different materials that need to be supplied. Previously, they were stored at several different locations, which made planning, transport and handling time-consuming. Today, with the help of Kasto, Keller has created  a made-to-measure storage and material flow solution that he designed as part of his technician's training course.

The automated sheet metal storage and loading system fitted to the laser cutting machine is supplied directly with material from a Kasto Unitower B 3.0 computer-controlled sheet metal storage system, which has 89 pallet storage locations. 

The pallets hold 3000 x 1500mm sheets and can accommodate a stack 90mm high of different sheet types, mainly steel, stainless steel and aluminium in thicknesses from 0.5 to 20mm. Each location has a load capacity of 3t, so about 270t of sheet metal are available for immediate delivery. 

The storage system offers high availability, so the company can react quickly to customer needs. To transfer system pallets to and from storage and to supply sheets directly to the loading system of the laser cutting cell, the system has one station with a transverse carriage and one with a longitudinal carriage. To allow unpacked sheet to be loaded and unloaded by forklift truck or crane, the transverse carriage has a hydraulic piston lifter.

The longitudinal carriage has a drop-off position for transfer of system pallets to and from storage and the return of pallets that are no longer needed during laser cutting. Both stations and carriages have an optical contour monitor to ensure safety in any pallet loading status and prevent malfunctions. 

The operating gantry crane is responsible for pallet and sheet handling. It operates at a maximum speed of 22m/min in the vertical direction, while pallet push/pull speed is 20m/min. The Kasto EasyControl can be operated automatically or manually and handles order management for the complete storage system. There is also an interface to the laser cutting machine’s loading system to ensure smooth material transfer. 

Martin Stöckle, sales team leader at Kasto, explains: "By using the standard versions of the Unitower B 3.0 sheet storage tower and adapting the arrangement of the transverse and longitudinal stations, we were able to design a very compact system. 

“The space available was limited due to the layout of the laser cutting cell and other equipment, so we suggested installing the tower store behind an existing wall to transport the pallets to the loading system area by the shortest possible route." 

This minimises delivery times, so laser cutting machine can be operated almost continuously during the 1.5 manned shifts and unattended for the remainder of the 24h. Overall, an increase in productivity of about 25% has been achieved compared with previous material storage practices. The ability to keep track of the material inventory enables the company to optimise stock levels and reduce scrap.

Harald Keller concluded: "As well as increasing productivity by a quarter, the risk of material damage caused by frequent handling and transportation has been minimised, and working conditions are safer and more convenient. We have improved use of the laser cutting system thanks to shorter idle times and have eliminated transport from external storage locations and hence the need for weather protection. 

“We now have a compact, cost-effective, 3D storage solution for a wider range of materials and are better able to respond quickly to customer requirements.”