Upgrading a large chemical plant from a manual process to one with an integrated IT infrastructure doesn’t happen overnight. It takes time and planning to implement a system that controls all manufacturing elements, material handling, equipment, personnel, specifications and procedures, and then integrates everything with business and operation systems.
But for chemical and other process-based companies, this transition to an integrated IT infrastructure is essential to keep up with customer demands and ensure profitability. Manufacturers rely on this kind of operation for flexible supply chains, synchronized production and real-time plant visibility.
Back in 2002, we began a journey that would bring the Chemetall Group's plant in Langelsheim, Germany, from a manual process to one that completely integrates MES into the process and feeds data to SAP. The Langelsheim plant produces advanced specialty chemicals used as surface treatments in automotive and aerospace applications (Figure 1). Thirteen years ago, all of the 1,500 finished products coming from the plant were manually produced. The batch plant had 30 reactors, 20 storage tanks, four pre-weighs and several filling stations.
The upgrade was to be a pilot for a standard solution that could be easily supported on a global basis. Considering all of Chemetall’s requirements and business goals, ATS Automation’s Process Automation Solutions designed a solution based on Siemens Simatic products. We were well qualified for the project, since we specialize in all kinds of automation topics for process industries, including basic engineering consultation, detail engineering, over-specifications, implementation, procurement, functional safety topics, qualifications and validation topics, specifically in regulated industries.
First taste of automation
When we began the project, personnel at the plant manually operated the reactors. Buttons were pushed to start and stop mixing motors. All dosing and level measurements were manual as well.
As a result, ensuring accurate dosing was very challenging back then, requiring close attention on the part of the operators. Also, cycle times varied and data entries weren't consistent. Fixing these problems was the justification for the project, and would also serve as an example for a global rollout. We approached the project in standardized phases. Since everything was manual, we weren't able to automate everything all at once, and required operator guidance for material identification purposes.
We first introduced barcode scanning where operators used material scanners to identify the materials. Production orders were downloaded into Batch ERP—one of only five installed worldwide, I believe—which would feed information back to the Simatic PCS 7 process control system. Batch ERP was its standard interface to SAP PP-PI to download product and order information into a sequential database. This database required SQL scripting to extract data, which needed to be prepared before the batch started. RSBatch software was used to handle the batch control recipes.
Additionally, we introduced tables for material tracking and picking systems, as well as for lot reporting and batch history. At the time, this was quite innovative, but today this would be considered spaghetti code.
Maximizing supply chain flexibility
Over the years, the plant focused on maximizing supply chain flexibility, but as time went on, it became clear that a consistent solution was needed at all levels, from the controller through MES. Standard interfaces were needed. System maintenance had to be minimized. The process had to be highly reliable and comply with manufacturing regulations and standards.
In 2008, we were again given the job to upgrade the plant. Batch ERP was not supported anymore, so there was a high risk of potential system breakdowns that could cause significant production losses for Chemetall. The scope of work included project management, design specification, detail engineering, supply and design of the PCS and MES components, configuration of PCS and MES, supply and configuration of the bar code scanning system, factory acceptance test, commissioning and training. The main challenges included migrating the original, tailor-made applications and introducing intelligent mobile devices. We also had to extend the vertical integration into SAP to include quality data.
To meet Chemetall’s operational expectations, we introduced an integrated Siemens automation system. The system would provide a state-of-the-art and well supported integrated solution, minimize custom interfaces, and reduce operational complexity. The project included upgrading the PCS 7 system to V7.1 SP2 to provide the basis for the highly integrated, reliable production system. It also included five AS416 controllers, a redundant WinCC Server, six terminals, a Simatic IT Server, redundant Simatic Batch software, and mobile terminals with RF scanners.
IT brings improvements
The main part of the project focused on replacing the existing Batch/MES components with a homogenous solution based on Simatic Batch and Simatic IT V6.4. Simatic IT provided a standard data-integration service interface to PP-PI from SAP. There's a business logic production module, and Business Process Modeling (BPM) software implements the business rules and some functions to check if the material and units were available. There was a lot of functionality in this business logic production.
We introduced a client application built for material tracking and picking functionality. The remote scanners were directly implemented into Simatic IT, which also offered many different modules, depending on functions required.
An important part of the Simatic IT platform was its Production Suite that links the ERP with the PCS 7 process control system (Figure 2). It gave the Langelsheim plant's operators and managers real-time plant performance visibility on a business performance level, which increased the efficiency of the overall supply chain. All the applications used Production Suite, including Simatic IT Historian that was used for data collection and comprehensive reporting functionalities, continuous trending and batch comparisons.
Production Suite also combined a business process modeler with a collection of highly integrated components. It handles the plant’s production management and execution, coordinated systems with other plants, standardized production across the entire enterprise, and kept manufacturing processes aligned with supply chain activities. It also gave Chemetall complete material genealogy and full backward or forward traceability for cost-efficient regulatory compliance and material management, as well as plant performance analysis for production cost optimization.
Production orders scheduled in SAP R/3 PP-PI were downloaded into Simatic IT, where they were split into batches inside Simatic Batch and special picking orders in Simatic IT, and displayed on wireless intelligent handheld scanners. The status of the process orders and other process data, such as material consumptions of bulk material or manually handled raw materials, were transmitted back to SAP to ensure timely updates of ERP warehousing.
Following the successful upgrade at the Langelsheim plant, we installed a nearly identical Siemens Simatic automation system in 2011 at Chemetall's greenfield site in Jackson, Mich.
From an installation point of view, engineering time was shortened by about 30-35%. It was supposed to be a nine-month project, but it only took six months. The engineering time improved because recipes were automatically handled, and there was no need to manually create batches. Also, the ISA88 concept helped us introduce equipment modules in phases to help modify and adjust production, as well as introduce new products, without needing to change code.
Success spurs global rollout
The positive results of the pilot project in Jackson and a subsequent U.S. rollout both met Chemetall’s expectations. The company can better track materials with its barcode scanners in every production step throughout the facilities, and directly connect to PCS 7.
Productivity at the pilot plant increased by 15% because of Simatic IT’s integrated data handling and automatic consumption reporting to SAP. Better dosing and optimized outflow contributed to the improvement as well. Also, warehouse stock was reduced by 20% after moving from build-to-stock to build-to-order production.
Finally, customer satisfaction increased significantly due to increases in quality, consistency and punctuality of delivery. Delivery date targets were improved by 15%, all manual actions were nearly eliminated, and the adjustment rate was improved by 22%.
Today, Chemetall has standardized on Simatic IT globally. It's the standard interface for Simatic products, but it can also talk to third-party PLCs and other components. The company has more than 20 production sites globally with different automation formats and landscapes, including Siemens, ABB, Honeywell and Rockwell. There are projects ongoing in several countries globally to further harmonize the company's process automation. For now, the present rollout is well under way, and the Siemens global presence and our engineering force make a perfect base for future success.
— Ruediger Trobisch is director of manufacturing and business integration at Process Automation Solutions GmbH, an ATS company.
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