An application report
An advanced, efficient warehouse management system contributes greatly to the efficiency and profitability of a company. For this reason, esco european salt company GmbH & Co. KG, a subsidiary of K+S AG, was the first company in the world to opt for a modern system in which the stacker cranes and conveyor technology of the fully automated high-bay warehouse are directly integrated into SAP-EWM.
In 2006, Artschwager + Kohl Software GmbH was commissioned to modernise the hardware and program a completely new software for the conveyor technology and to integrate the stacker cranes into SAP EWM. All work was to be designed in such a way that production and warehouse operations were not obstructed during the modernisation process.
Greater efficiency: Production and warehouse in a single system
As part of its long-term growth strategy, in 2006 esco was faced with the decision to modernise the entire warehouse control system in Bernburg. At the time, esco was working with a combination of SAP ERP with several stand-alone applications for warehouse technology and automation, material flow control and warehouse management.
The system was based on outdated Siemens S5 controllers and IT solutions for which support was no longer provided. Smooth communication between the ERP and warehouse management was no longer guaranteed. This meant that current warehouse stocks could no longer be safely mapped in the SAP system.
In the course of planning the necessary modernisation measures, the opportunity presented itself to slim down the entire system architecture and make it more efficient. The challenge was to find a solution that would permit communication without detours via middleware and subsystems.
New hardware and software for conveyor technology and stacker cranes
As a first step, Artschwager + Kohl replaced the Siemens S5 controllers in the conveyor system with S7 controllers. This also required the programming of completely new software to link the conveyor system and all stacker cranes directly to the new SAP Extended Warehouse Management (EWM) with integrated material flow control (MFC).
The S7 controllers of the pallet conveyor technology and the stacker cranes communicate in the system set up by A+K with SAP EWM via a central PLC. This PLC thus functions as a router. It forwards all telegrams from SAP EWM to the corresponding S7 controllers. Conversely, the telegrams from the various S7 controllers are bundled and sent to SAP EWM.
This ensures reliable communication from end point to end point. This system with a “router PLC” as “single point of communication” has obvious advantages for operation: It is now possible to log all plant communication and check whether events are processed in the correct order – a significant simplification when, for example, process errors need to be detected and dealt with quickly.
A pioneering achievement: Conveyor technology and stacker cranes in SAP EWM for the first time
The main challenge was to implement the new system without affecting ongoing production and logistics processes. For this reason, the new software, with all its links to SAP EWM and to the stacker cranes, was first tested in its entirety in the offices via VPN connections with partner companies. The system was then implemented at esco on a trial basis over the course of three weekends. After the third test weekend had also gone without a hitch, the new system could be put into live operation. Since then, the esco systems have been running without any problems.
The undertaking was also particularly challenging for Artschwager + Kohl in that it was the first time ever in the world that the warehouse control and conveyor technology had been linked to SAP EWM, which meant that they were unable to draw on experience from previous projects.
The solution developed by Artschwager + Kohl now combines the communication of the stacker cranes and the pallet conveyor controls, pallet data tracking and visualisation from packaging and bagging, palletising, warehousing, stacker cranes and retrieval to route planning and rail loading with SAP EWM.
Manfred Eberl, head of production above ground at esco, was pleased with the successful progress of the modernisation project: “In retrospect, we can say that it worked outstandingly well. We stayed within our budget and time frame – very few projects run that smoothly”.
Scope of services