Manufacturing Control Systems Bridge Production and IT
In recent years, manufacturing execution systems (MES) and process control systems (PCS) have gained wide acceptance in pharmaceutical and biotech industries due to the adoption of industry standards and technology advancements. PCS for bulk therapeutic and biotherapeutic manufacturing achieved uniformity in the past decade thanks to the establishment of the ANSI/ISA-88 models for batch control.
In recent years, manufacturing execution systems (MES) and process control systems (PCS) have gained wide acceptance in pharmaceutical and biotech industries due to the adoption of industry standards and technology advancements. PCS for bulk therapeutic and biotherapeutic manufacturing achieved uniformity in the past decade thanks to the establishment of the ANSI/ISA-88 models for batch control. During the same period, a broader range of industries used MES and ANSI/ISA-95 standards to improve their manufacturing operations.
While MES and PCS found their place in the industry, they have typically been viewed as separate solutions within a manufacturing facility. This approach often led to a disparity of systems and organizations responsible for development and maintenance, further hindered by a lack of interoperability and dependence on custom interfaces for connectivity.
As companies pursue MES and process automation initiatives, they are often challenged by varying budgets, schedules, and project methods. The reason: automation is traditionally viewed as an engineering discipline, whereas MES is regarded as an IT function. However, in a recent project at a brownfield biotherapeutic manufacturing facility, a new aggregate approach referred to as a manufacturing control system (MCS) was put forth as a solution to provide a single environment for manufacturing operations and process automation, meeting all requirements of a paperless facility.
Common MES and PCS use batch management software integrated in most PCSs available today provides a robust solution for designing, modeling, and automating batch processes. It enables flexible recipe building and management using object-oriented recipe structures aligned with S88 models. Online tools allow users to manage multiple batches from the same window and navigate between displays based on batch execution activities.
S88 batch management applications for automated recipe management and unit procedural control reduce latencies and improve repeatability. This, in turn, improves production efficiency.
In a variety of industries, MES has proven effective in managing all production lifecycle steps, from materials receipt to product shipment. The technology and S95 standards assist production personnel in managing execution decisions and information, from the processes of planning and scheduling to production execution.
A typical MES provides specification management tools, allowing users to define materials, equipment, and procedures required for production. In many cases, the systems can be expanded to handle multiple production sites—enabling product development departments to deploy new products quickly or update existing product formulations.
ISA95 control hierarchy levels encompass areas controlled by multiple system platforms
Characteristically, MES benefits manufacturers by a providing scalable, Web-based architecture that is easy to deploy and maintain. As such, an MES can form the central system for synchronizing business systems with manufacturing and process control. Integration with other manufacturing systems can be achieved using Web services and industry standard technologies such as XML and OPC.
Despite the merits of MES, the technology alone cannot advance the state of manufacturing. This is because traditional paper-on-glass systems do not collect, organize, and manage all production information—particularly manufacturing and process data generated by the PCS.
Although MES applications have matured around integrated material management and paperless plant-floor operations, which provide significant production efficiencies and cost savings, often personnel still find themselves manually managing vast amounts of information. Users are required to refine production data so operations and quality decisions can be made in a timely manner.
Combining today's MES with batch control provides a beneficial architecture for activities such as material tracking/genealogy, barcode scanning, bills of material, work instructions, asset management, lab systems integration, and production dispatching and execution in single, unified environment.
MCS fills the gaps
The manufacturing control system (MCS) is the integration of MES and PCS technology to provide a single solution for production management, process automation, and reporting. This unified MCS design utilizes the strengths of MES for material management and plant floor applications and incorporates the latest advancements in PCS technology, particularly in the areas of automated recipe management and unit procedure control.
Tight integration of MES and process automation allows pharmaceutical and biotech manufacturers to move beyond paper-on-glass functionality and leverage all of the robust capabilities the two systems have to offer. These include electronic work instruction execution and workflows, material reporting, asset management, laboratory data logging, production dispatching, and electronic batch record (EBR) management.
Implementation of MCS strategy requires an open, standards-based programming interface allowing communication between MES and ERP solutions and business logic. Such integration enables users to access production-related information from the MES and business applications in real time. This connectivity, made possible by S95 Parts 1 and 2 defining ERP/MES communications standards, is a precursor to MES/PCS unification and a new level of plant-wide integration.
Within the integrated manufacturing architecture, MES serves as an interface to corporate level 3 and 4 systems, electronic document management systems, laboratory information systems, material requirements planning (MRP) systems, and enterprise resource planning (ERP) applications.
The MCS provides a platform for handling both inbound transactions (e.g., process orders and lab results) and outbound transactions (e.g., inventory updated and lab requests).
Benefits of unification
The upside of a unified MCS approach is best demonstrated through MES/PCS transactions, such as production execution, resource management, material tracking, and electronic work instruction management. Unit procedural control and phase execution with an MCS is more efficient than in a traditional environment with separate system domains. Operators see a unified interface with a common HMI environment, instructions, and displays.
With unified MCS architecture, orders from MRP come down to the plant floor through the MES. The MES automatically dispatches recipes based on required equipment status and availability, and executing them in the process control system. This innovative approach eliminates the traditional requirement for operators to check equipment status manually, assign equipment, load recipes, and initiate batch execution. Rather, the MES handles these activities as the operator fulfills the order at the PCS layer.
Consider a typical MCS batch processing application: After dispatching a unit procedure, the MES binds to the process unit for execution and starts the sequences. The PCS then executes phases within operations at the equipment level, performs automated tasks, and requests information from the MES.
At a typical pharmaceutical or biotech plant, operators must manage production resources and report the status of specified equipment in a paper log or database before a batch can be started or moved to the next stage. The MCS automates this procedure since the program phase in the PCS controls specific equipment. PCS's requests for information are handled by a transaction executed to the MES via an OPC service. The MES automatically allocates resources and performs arbitration should conflicts arise. This allows the automation process to continue without interruption.
For example, the PCS might issue a request such as, “This tank is needed; is it sterile?” The MES will respond, “Yes, you can acquire this resource because its status is correct for your requirements.” Once the operation is completed, the PCS phase will release the tank back to the MES with a message saying, “This equipment is returned with a status of dirty.” All this happens without operator intervention.
When it comes to material tracking and reporting, the PCS phase again interfaces directly with the MES, which in turn, interfaces with MRP as required for inventory updates. During execution of a particular phase, the system might say, “Material 'A' for the batch is needed.” The MES then reports, “The material's quality is acceptable and the expiration date has not been exceeded. Here is the quantity that should be added.” It then provides results regarding bar code scanning and performs system data verification at the point of use (e.g., when the material is introduced into the batch).
When tracking material consumption, the PCS can send a transaction notifying the MES that it is time, automatically or manually, to consume a particular additive or ingredient. As the automated steps execute, a procedure appears on the operator's screen with prompts for completing the task.
Under normal circumstances using disparate MES and PCS systems, the operator has to pull up a ticket or paper-on-glass in the MES environment to check the status of materials, and verify information indicating that he or she is adding the prescribed material. Then, acknowledge the material addition is complete and instruct the PCS to continue.
In the case of manually consumed materials, standard material-add pages prompt the operator to scan the required material and then automatically execute the quality checks prior to prompting the operator to deliver the material. For automatically added materials, the quality checks and consumption reporting are done without operator intervention unless required.
Electronic work instructions
The MCS strategy also revolutionizes handling electronic instructions and workflows, eliminating paper procedures. Unlike a standalone MES, the integrated system automatically presents instructions or workflows (i.e., SOPs) on the HMI screen whenever and wherever they are needed. Operators are no longer burdened with coordinating MES activities, while staying abreast of PCS execution. This enables a new level of plant production efficiency.
During a phase execution for instance, the system calls up standard faceplates on the process control graphic that prompts the operator whenever his or her attention is required. The operator is presented with an “action list” displaying phases with their instructions, a button to display the detailed instructions and, upon acknowledgement of the action, the type of signature required. Operator instructions can be signed off directly from the HMI page.
Likewise, in the middle of a phase, required manual actions can appear on the MES page as a workflow that includes a variety of MES activities the operator must follow. Once the tasks are completed, the technician acknowledges the work with an electronic signature and the PCS resumes automated control.
For pharmaceutical and biotech operations, the unified MCS not only delivers new automation capabilities, but also presents new ways to manage manufacturing complexity and improve operational efficiency. Industry analysts estimate that as much as 20% of a firm's costs of operations are associated with manufacturing, which means even modest operational improvements can have a significant financial impact.
For a plant's technology personnel, the MCS merges disparate MES and automation departments into an integrated production team that works hand-in-hand to optimize manufacturing operations. Under the new architecture, components such as work instructions, bills of materials, and asset definitions are supported in the MES, but requested from phases executed in the PCS.
As a result, the two departments interact to ensure components are correctly configured and managed. This closer collaboration enables a reduction of support staff between the two departments of more than one-third. Now the restructured groups can operate as a single organization rather than separate teams of engineers and IT specialists.
In addition, manufacturing personnel, quality departments, and engineering staff now utilize a single, unified system with a common environment for accessing production data, viewing process displays, and making critical operational decisions.
The MCS solution eliminates the need to manage paper batch records. The system provides electronic records of each batch of products produced, as well as the means to collect, store, and analyze data more efficiently. Documents within regulated environments can be created, reviewed, approved, and issued electronically in a collaborative manner with full change control by the respective departments. This approach simplifies the GMP-related document management process.
Manufacturers implementing MCS can streamline the effort required for regulatory compliance and expedite the release of manufactured product. The integrated system, with EBR and process automation information (i.e., alarms, unit control data, batch events, process history, etc.), enables easier compliance and verification. The plant's quality group can access robust, consolidated data assisting the review process prior to product release.
Previous paper-based systems required numerous weeks to collect paper records, review, reconcile discrepancies, and approve for release. Subsequent designs of disconnected MES and PCS architectures reduced the product release process to a couple of weeks, but the new MCS design is estimated to reduce this process to a few hours.
The integrated MCS system approach brings together information from key areas such as process control, MES, and laboratory systems. This facilitates the discovery of new opportunities to improve operational performance and drive down costs.
Pharmaceutical and biotech facilities gain a world-class solution providing a single source of centralized manufacturing data. No longer must PCS data be duplicated for the MES environment, and then migrated into the ERP system. Instead of distributing asset and process information between three different systems, users attain a single source of the truth. Equally important, an interoperable MCS design with Web/HTML-based applications and open, industry standard communications protocols provides a secure and predictable path for future technology investments. Potential directions can include RFID, biometric security, and wireless hand-held mobile devices.
In the life sciences industry, the constant challenges for manufacturing are efficient, streamlined operations with fewer errors, greater consistency, and unfailing compliance with FDA regulations. Manufacturers seek shorter product cycle times, faster product changeover, and better maintenance scheduling, all adding up to improved operational performance. To meet these challenges, a seamless MCS architecture providing common electronic batch records and production reporting for automation and production management with reliable traceability (i.e., materials, equipment, and personnel) can now be employed.
Ronald E. Menendez is senior automation engineer for Genentech. Reach him at email@example.com .
Darrell Tanner is technical lead for Honeywell Process Solutions. Reach him at firstname.lastname@example.org .
Portions of this article were published previously in Pharmaceutical Engineering, March/April 2007, volume 27, no. 2. Reprinted with permission from ISPE and Pharmaceutical Engineering.