For approximately the last decade, many of us have heard that we need to digitize industry. That comes as a surprise, since for the last 50 years or more industry has been digital. What are they talking about?
It is at this stage, the Manufacturing Execution System (MES), that we finally see what these people have been talking about.
MES is the connectivity of operational technology (Levels 0 through 2) to information technology (Level 4 where the Enterprise Resource Planning/ERP system lives). MES is everything to do with implementing the security addressed in the prior article and all applications that merge operational technology and information technology.
An example is batch processing. The ERP records a customer order for a quantity of a grade to be sent to a customer by a certain date, and we know what they are going to pay and confirm when the order has been delivered, the invoice submitted, and when it is paid. MES gets this order and figures out what equipment and resources are available to make this grade and meet schedule. When those resources are acquired, the batch processing is sequenced through the production process. When complete, the batch status and associated reports are sent up to ERP so that the order can be shipped and invoiced.
While batch processing has been around for a long time at the Level 1 and 2 layers, today we have the digital connectivity through the enterprise. MES is where nearly all the 4th industrial era development has happened.
A lot goes on at this layer. An example is order slotting. In the batch example given, how do we get the order scheduled without disrupting all the other pending orders? MES applications that are aware of all the orders at Level 4 need to optimize the resources at operational levels to do this. That means the order slotting application needs to know resources availability and performance. Performance is reported in terms of Overall Equipment Effectiveness (OEE). With OEE, we know whether we can process the batch by the deadline. If the resources are available and the OEE is high enough, while recognizing deadline constraints and priorities on other orders, we can find the optimal order slotting to meet all objectives optimally.
What is important is that the MES layer allows this to happen automatically, meaning we don’t need to manually write down information, make phone calls, edit spreadsheets, and waste a lot of time reworking the plan. This is what we mean by digitize industry. It is almost entirely at this level where the 4th industrial era happens.
MES is more mature in regulated industries like food and pharmaceuticals because the need is critical. Providing the lot tracking and quality records mandated by regulations make this functionality required in order to produce.
In the paper industry, we are far behind in this domain. We can make paper without it, but we don’t make the best use of our labor time and data when ERP financial data is isolated from operational data. The other reason is that many facilities still struggle with their operational systems, making it impractical for MES to be successfully implemented. There are mills with antiquated control systems where they can only find spare parts on eBay. There are mills with unpatched Windows 95 machines connected to their control system with default accounts and passwords. E&I resources are thin, so level 0 devices are barely maintained. The vast majority of PID loops are either underperforming or inducing variation because tuning is not maintained.
Mills that invest in the necessary resources to maintain Level 0 through 2 operational layers can become the high performing industry leaders with MES. Those that don’t will continue to be mired in perpetual 3rd industrial era challenges.
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