Applying Automation to Batch Manufacturing Using Industry Standards By Bruce Jensen & Marcus Tennant Yokogawa Corporation of America Sugarland, TX
Abstract
Batch processes in many industries, including grease manufacturing, are built to achieve very flexible manufacturing requirements. Often, when automating a batch process, that flexibility is lost making it difficult for operators to introduce new products and make process modiἀcations. Developed and reἀned over the past 20 years, the ISA Batch Standard (ISA 88) has become a commonly understood approach to communicate batch system requirements across R&D, process engineering and control disciplines, and has enabled manufactures to build flexible and highly automated batch systems. This presentation will outline the basics of the ISA-88 standard and provide an overview of how it has helped many different companies achieve agile and flexible manufacturing in highly automated batch systems.
Overview of Batch Processing
In the universe of manufacturing, there are two broad ways to produce items for mass markets. On one end of the spectrum, a discrete manufacturer produces things: cars, electronics, appliances and tools. This is where assembly lines with robots and high speed packaging are very prevalent. At the other end, process manufactures make material: gasoline, diesel fuel, paper, and bulk chemicals. Both of these manufacturing worlds share many common traits. They both strive for high levels of automation to help them meet market demands by producing efficiently and at a high rate of speed. Some products for more specialized markets do not have to be produced in quantities that justify major manufacturing efforts. There are many opportunities
for more complex and customized production. For products where the marketplace demands more limited qualities such as pharmaceuticals, food, and many specialty chemicals, including greases and lubricants, manufacturers walk a ἀne line between producing products that are considered commodities on one hand, while still being very specialized to meet customers’ exacting standards.
Issues with Automation in Batch Production Processes
For batch processing, the biggest advantage is often the capability to customize each batch to meet a customer’s requirements. With the advent of computer-based control system technology, the continuous process world quickly adopted the DCS (distributed control system) to automate control functions, replacing pneumatic and single loop analog control. On the discrete manufacturing side, the PLC (programmable logic controller) was developed to replace complicated relaybased machine controls used in many industries. For batch manufacturers, the introduction of computerbased automation and control technology put them in a quandary. There were certainly recognizable beneἀts to automating a batch process: improved quality, consistency and lower manufacturing costs, but there were downsides as well. In batch manufacturing, procedural control is a major requirement and programming often became very complex to allow users the ability to switch product manufacturing procedures. Typically the systems were coded by very talented control engineers who understood the embedded procedural
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