The initial situation
The company K+S, formerly “esco – european salt company GmbH & Co. KG” is the leading salt producer in Europe. In the largest plant in Bernburg, NaCl has been mined for over 100 years with a degree of purity of over 99%. In Bernburg, industrial salts as well as salt for the food industry are produced. Very large quantities are shipped by rail as loose goods. Furthermore, very large quantities are also packed as big bags and bagged goods. These are palletised and temporarily stored in a high-bay warehouse for dispatch.
The production warehouse consists of 6 aisles, each with one stacker crane, at that time controlled by one S5 controller each, two floors for storage and retrieval with two S5 945s, an obsolete WMS based on IBM RS6000 and a material flow controller. Support was no longer available for the WMS and the MFC, and the spare parts situation for the S5 controls was equally precarious. The consequence: The system technology of the warehouse had to be modernised.
K+S was already using SAP ERP at that time. With SAP EWM becoming available, the decision was practically a foregone conclusion. K+S resolved to be the first company in the world to introduce a production warehouse with SAP EWM.
The concept phase
A+K was commissioned by K+S to create a consistent concept for replacement. This included the existing WMS, the material flow controller (MFC), exchanging the S5 hardware to S7 hardware, redesigning the complete control software, integrating the stacker cranes and the complete communication of all controls with SAP EWM. In addition, a central Scada system was to be installed for the control room. The Scada system had to include all pallet conveyor and stacker crane controls as well as all communication links, especially to SAP EWM.
A+K was responsible for the communication and technical coordination of all trades. During the engineering phase, communication took place in a two-week cycle, prior to commissioning in a weekly cycle, during commissioning and start-up daily on site.
A+K worked out a comprehensive detailed concept with all parties involved. This contained a complete description of all systems, all communication paths, all process and communication sequences as swimlane diagrams, all telegrams, all error handling.
Likewise, all procedures for project implementation, the services to be provided by all parties involved, milestone concepts and start-up concepts were defined and documented.
The commissioning process
The esco company (now K+S) was not able to interrupt production operations for a long period of time. For this reason, all interfaces between the control systems and SAP EWM were jointly tested in the office in advance. This included all interfaces between SAP and the main PLC as well as all interfaces between the main PLC, all conveyor technology PLCs and all stacker crane PLCs.
Furthermore, the completely newly created control software for over 100 pallet track segments was also pre-tested in the office with simulators.
The actual integration tests took place on two weekends, once on Saturday and once on Sunday. After the test, the system was switched back to the old systems, including the old WMS, the old MFC, the old S5 controls for the conveyor system and the old S5 controls in the stacker cranes.
On the third test weekend, the modernised plant was in use by regular production personnel. After they gave the “green light” on Sunday afternoon, the go-live of the new systems followed on Monday.
During the one-week start-up support, the new systems still had minor defects. However, this was to be expected after such a comprehensive modernisation. There were a few minor timing problems in the communication in SAP EWM, the user interfaces of the new operator panels still had to be improved slightly and the order placement for the two cross-transfer carriages competing for space on a single track still had to be optimised somewhat to achieve higher throughput. All optimisation work could be completed during the start-up support phase.
The project was challenging, but thanks to the structured project implementation, it was still very manageable.
The upstream reengineering of the plant made it completely transparent. As a result, every party involved could be provided with exactly the information they needed for their work.
The detailed description of all processes and interfaces provided a sound basis for the fast and secure integration process during the two test weekends.
The integrated logger for recording all telegrams documented in writing whether all telegrams and processes were running as planned.
Since the go-live in 2008, the systems have been working trouble-free to this day.
Scope of services of A+K
- Reengineering of the existing WMS, MFC and PLC systems, reverse documentation of the complete storage system.
- Creation of a comprehensive modernisation concept, coordination of all processes and telegrams to all companies and systems involved
- Creation of an implementation plan for the changeover phase including the decommissioning options in the event the go-live should fail.
- Creation of S7 software for pallet conveyor controls
- Creation of S7 software for material flow control
- Creation of S7 software for order placement to six stacker cranes
- Creation of S7 software for communication with SAP EWM
- Creation of Scada system with plant visualisation, reporting system and weak-point analysis
- Creation of logs of all communication paths and telegrams
“SAP EWM” means SAP Extended Warehouse Management. With the EWM warehouse management system developed by SAP, intralogistic processes can be recorded and monitored with ease.
As an IT warehouse management system, SAP EWM is a key element of SAP SCM (SAP Supply Chain Management). In connection with other SAP modules, all important logistics processes can be managed, organised and optimised.
The integrated SAP Material Flow System (SAP MFS) allows the control of highly automated intralogistic systems.
Functional areas of SAP EWM:
- Storage location management
- Recording of all goods movements
- Monitoring of all warehouse movements
- Warehouse control
As one of the leading warehouse management systems, SAP EWM even enables you to enter the world of Logistics 4.0.
The advantages of SAP EWM:
- Efficient, on-schedule order processing
- Support of all relevant processes
- Flexible resource management
- High transparency of all inventories and processes
- Integration in SAP enterprise resource planning modules
- Simple coupling with automatic systems
- Digital, mobile order processing
The SAP warehouse management system integrated in SAP ERP is often used by medium-sized companies whose warehouse management is not overly complex. SAP EWM Extended Warehouse Management is ideal for larger companies with complex logistics systems and a high degree of automation.