Overall Equipment Effectiveness (OEE) for Batch Manufacturing

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1 Page 1 of 6 White Paper on Overall Equipment Effectiveness (OEE) for Batch Manufacturing

2 Page 2 of 6 Introduction Manufacturers are in business to generate revenue and profits by adding value to the materials which are used to make the products that customers want to buy. In most companies this involves the use of equipment. To add value efficiently, it is important to run this equipment effectively, with as little waste as possible. Overall Equipment Effectiveness (OEE) is a metric that manufacturing companies use to improve performance in their business. As one number, OEE percentage is of limited use, but with visibility to the sub-components used for calculating the OEE metric, your employees can identify where the focus needs to be over both short and long timelines. Using OEE metrics, dashboards and reports, your management team will know that production are going to meet customer orders because efforts can be quickly focused on fixing any problem areas in order to always meet customer orders. OEE will get you more from your resources, both equipment and people. It helps companies get the most out of their business and helps improve bottom line profitability. OEE gives a balanced measurement to support improvement and profitability because it gives a complete picture of the equipment health, monitors the equipment operations that add value, provides accurate impartial snapshots which promotes openness in information sharing and OEE fosters a no-blame approach in handling equipment related issues. Batch manufacturing in life science companies is typically driven by automation recipes, which are designed in line with ISA88 for Batch Control Standards. In batch manufacturing, equipment trains are not necessarily fixed in the way that assembly, discrete or continuous manufacturing have lines of fixed equipment and operations which are carried out for a route through relevant work units. In batch manufacturing, equipment decisions can be made during the control recipe execution for many processes, therefore there is an inter-dependency which exists between the control system recipe execution and deriving the exact process train that was used. In many cases therefore, batch process information relationships cannot be pre-configured as master data. This is why OEE for batch is calculated differently and OEE point solutions from other manufacturing types won t give you what you need as a batch manufacturer. The Details Not having fixed equipment for many processes makes the calculation of Overall Equipment Effectiveness (OEE) more complex for batch processes than it is for discrete manufacturing, where there is only an operations layer routed through predetermined work units/machine stages. The entire manufacturing spectrum in fact deserves their own method for calculating OEE assembly, discrete, batch and continuous: OEE a, OEE d, OEE b and OEE c.

3 Page 3 of 6 To understand batch requirements, let us firstly explain the typical discrete calculation. OEE for discrete manufacturing can be calculated using the following: OEE d = Availability Performance Quality where Availability d = 100 Run Time Planned Production Time Performance d = 100 Quantity Made Theoretical Quantity (based on theoretical cycle time and rate of production) Quality d = 100 Quantity of Good Parts Total Quantity Made Availability is a comparison of the potential operating time and the time in which the machine is actually making products. Performance is a comparison of the actual output with what the machine should be producing in the same time frame. Quality is a comparison of the number of parts/products made and the number of parts/products that meet the customer s specifications. For batch manufacturing the OEE components are derived from different data and the terminology used is different, so we ll use the terminology batch manufacturing uses. OEE b = Availability Performance Quality To begin with, let s look at Availability for batch manufacturing: Availability b = 100 Operating Time Planned Production Time Which = 100 (Planned Production Time Downtime) (Batch Duration Scheduled Time) The Operating Time equates to the Planned Production Time minus the Downtime. The Planned Production Time equates to the Batch Duration minus the Scheduled Time. So, where do we get the data from for these times?

4 Page 4 of 6 The Batch Duration can be calculated from the data in the automation control system (e.g. Industrial IT 800xa, DeltaV, ibatch, FactoryTalk, InBatch, Simatic Batch etc.). A scripted interface connects to the automation control recipe data to get the overall duration of the control recipe. The Scheduled Time is the time between a batch being scheduled and the time it goes to the running state. This can be calculated from the data in the MRP, ERP, other planner or control system batch scheduler and from the time date stamp when the batch control recipe goes to the running state. A scripted interface connects to the system that you use for scheduling and another interface connects to the control system for the running state time date stamp. The Downtime can be calculated from the duration of a batch control sequence in a particular state: typically stopped, aborted and held. A scripted interface connects to your control system to extract the duration between each state change in line with ISA88. We can therefore calculate Downtime for batch processes on a prescribed time basis (30 minutes, hourly etc.) as the processes are running, making allowance for parallel path execution and hold propagation (phase, operation or unit procedure) for each equipment/process units. Having the visibility to these batch downtime durations by process unit, and control recipe operation as well as for the overall batch helps you understand where the issues and challenges are with your process equipment. Other Downtime events can be entered by operators against each batch. Additional time is also lost between batches and campaigns and this time can be tracked against the shift. We refer to this as inter-production downtime. Operators can enter the duration and reason from a configurable multi-level hierarchy of downtime groups and reasons. Now, let s look at Performance for batch manufacturing: Performance b = 100 Total Product Quantity (Theoretical Product Rate Operating Time ) The Total Product Quantity is usually X kg for primary and secondary pharmaceutical manufacturing, but it can also be a concentration or assay for biotech products. This value may be automatically retrieved from the control system, batch historian, ERP system, LIMS or other in-house system via a scripted interface. Alternatively users can have the ability to enter this figure manually, but human touch is to be avoided if possible due to errors and ease of use. The Theoretical Product Rate is typically measured in kg/hr for batch processing. This is a theoretical rate against the entire process because the product may be in solution during many of the processing steps. The rate is essentially an ideal throughput for each process unit in terms of capacity over time. Ideal times can be approximated against pre-defined recipe operations from the control system. The Operating Time, mentioned earlier in this document is the Planned Production Time minus the Downtime.

5 Page 5 of 6 Now, let s look at Quality for batch manufacturing: Quality b = 100 (Actual Product Yield Target Product Yield) The Target Product Yield can be configured for a manufactured material. The Actual Product Yield value may be automatically retrieved from the control system, batch historian, ERP system, LIMS or other in-house system via a scripted interface. Alternatively users can have the ability to enter this figure manually, but human touch is to be avoided if possible due to errors and ease of use. The Benefits OEE for batch manufacturing improves operating performance by: Providing automatic visibility to batch manufacturing data (OEE, availability, performance & quality - no more tedious spreadsheets Tracking both your control system batch sequence downtime events per process unit as well as other manual downtime events - get more from all resources Recording and reporting downtime event reasons (pre-defined and/or ad-hoc reasons) when the big problems are fixed - 80% of the effects come from 20% of the causes - fix them first to get to steady state operation Tracking bottleneck takt times and overall cycle time for each process - know that you are definitely going to meet customer orders Educating the work force to understand availability, performance and quality metrics and where to focus efforts - continuous & cultural improvement Attracting more manufacturing business by showing that your process plant in in good shape - global metrics are coming, adopt KPIs early, but report when ready Trending multiple batches for comparison and analysis of downtime, run time and yield

6 Page 6 of 6 The Conclusion Shopfloor-Online can deliver huge benefits to your batch manufacturing facility. Our browser based application can extract batch execution data from your control systems at regular time intervals, derive the equipment train and calculate recipe execution state change durations for batch processing downtime. Shopfloor-Online can then automatically lists the downtime events by shift, batch, process unit, process cell (equipment train). Other downtime events can either be triggered by an event or manually created and entered by the work force. Shopfloor-Online can connect to your manufacturing systems from MRP/ERP to Production Schedulers to Control Systems to LIMS to pull the data required to calculate Availability, Performance and Quality components of OEE. Get the visibility that you need to your manufacturing operations and get more from your assets with Shopfloor-Online OEE for Batch manufacturing, and increase your cash, reduce your costs and support faster new product introductions at the same time. Have a look at our sectors page for more relevant functionality for your life science manufacturing operations: Please contact us for more information about Shopfloor-Online: info@lzlifescience.com or sales@lzlifescience.com Online Form or Telephone: