Modular Automation Allows for Food Manufacturing Flexibility
From the PC to the Internet revolution, standard, modular software objects are the key to easier manufacturing agility and integration.
By Bob Sperber, Plant Operations Editor | 06/06/2011
The board of directors for Denmark-based dairy Arla Foods has spent a good deal of the spring deliberating ongoing consolidations that are bringing greater capacities to larger plants.
"To avoid empty plants a few years down the line, we have to react now," said executive vice president Jais Valeur, commenting in April on a small plant closing. "If we don't, production costs will be higher and the milk price paid to our owners will fall."
Another Arla executive has spent years improving the company's ability to adapt to changing economic, manufacturing and customer requirements. "As time goes on, we have found that we have to produce more orders and handle more and different kinds of product and packaging requirements for our customers," says Arne Svendsen, Arla's director of global manufacturing information technology.
"Customers like Starbucks or the Walmarts and Tescos will reject any product that does not deliver the right, consistent quality every time," he says. "And they want their deliveries when and where they want them. These are fair requirements and part of the supply chain game."
In food & beverage processing these days, flexibility wrestles with consistency at every turn. From meeting supply chain needs to modifying production lines to adapting recipes based on changing raw materials -- from fruit to cheese, in Arla's case – you gotta stay flexible. That can be especially difficult in a biological process, such as cheese-making. "We don't produce exactly the same thing every time as if we were building cars," says Svendsen. Even so, "tolerances for variation today are much more narrow than they were even a few years ago." His global team is applying data-driven systems to stabilize the vagaries of man, machine and Mother Nature herself.
And that's why, Svendsen says, "flexibility to us also means having a standard MES [manufacturing execution system] platform with a standard interface to SAP." Since 2002, a "One Arla" company initiative led the company to standardize on SAP (www.SAP.com) enterprise software. More recently, the company standardized its plant information systems on MES software from Wonderware (www.wonderware.com) — with installs at 35 plants of a total 65 in the last six years, with more to come.
Having a standard MES with standard modules for recipe-handing, quality management and data collection, among other functions, is "one of our strongest weapons in staying competitive," Svendsen says. Data coming up from the process lets the company access the data needed to get a "crystal clear picture of variability, yield and performance across every site," he says, using automated, aggregated overall equipment effectiveness readings in real time. The same data contribute to key performance indicators from the plant to the corporate office.
Estimated benefits of the SAP-Wonderware integration initiative include reduced work hours in daily operations; process and scheduling improvements through more responsive reporting; enhanced compliance to food safety requirements; reduced stoppages/downtime; and improved quality management.
Tech-wise, standardizing on a single MES platform serves as a layer of "data abstraction" above the machine control layer. That way, plants can gather data "no matter if they have Siemens, Rockwell or other vendors' controls installed," says Svendsen. So, for example, "a batch report looks the same whether it's a powder plant or a cheese plant or a milk plant. And that's probably where we get the most benefit."
From Microsoft to the Internet
For Arla and others who standardize on key vendors at various levels, current software allows a much greater level of off-the-shelf integration. Standards shared by Wonderware, SAP and most other leading automation and business system sellers have come in the wake of the personal computer revolution.
For decades, Microsoft's underlying technology has been the de facto standard for sharing data between plant software applications. Standards were based on Microsoft-based SQL server-type databases and other means of mapping data from point A to point B. For example, in the mid-1990s, Object Linking and Embedding for Process Control (OPC) eliminated the need for every software vendor to develop custom interfaces to every controller made, as well as other devices and software packages.
Vendors used to create vast collections of custom-programmed interfaces, which for some formed the basis for entire marketing campaigns. OPC eliminated those custom drivers when it provided a standard, object-oriented interface wrapper into which each vendor programmed device specifics.
The standard, from an OPC Foundation (www.opcfoundation.org) comprised of vendors as well as users, eliminated custom interfaces. This let all parties shift their focus from redundant programming chores to features that add value to manufacturing processes.
OPC has since proliferated into variants. OPC DA (for Data Access) provided a standard format to share data between applications in real time, eliminating custom-programmed drivers from the world of HMI/SCADA software packages. OPC AE (Alarm and Events), provided transactional, on-demand data transfers. Others specifically addressed historical data, batch data, server networks and more, including handling data formatted in XML, the language of the Internet.
OPC UA (Unified Architecture) is the latest and most ambitious effort. It began life in a 2008 first draft, and continues development to shed its Microsoft object-model underpinnings for the Internet standards of the World Wide WebConsortium, or W3C.
Modular machines, like Russian dolls