As I walked into the control room the first thing I heard was, “Why can’t I commission this transmitter?” The technician was pointing to the screen where he was trying to commission some Foundation fieldbus transmitters that had been taken out for service. At least this time he’d remembered to decommission them first.
A major part of today’s communication revolves around Ethernet networking. In our world, this is used for either communications or I/O control. The current state-of-the-art network hardware makes the implementation of these types of networks extremely easy and secure. The fact that this is the same technology that is used in every corporation’s IT department makes it even more attractive.
In the last post I gave you some homework around the idea of operational excellence. I hope you did your homework and learned some things.
Leaving Project Specifications Blank or TBA is a Recipe for Project Trouble
Much has been written on the subject of creating legal contracts, often including statements like, “Good contracts make for good clients,” and “Good contracts lead to good customer relationships.” Contracts are important. In addition to stating legal and financial requirements, contracts define what is to be done for the client. Just as important as contracts, proper specifications are needed to identify clearly how the contract requirements are to be satisfied.
After being involved in a number of migration projects, I’m surprised at how few of these considered taking advantage of the extra capabilities of fieldbus-based instruments, drives and positioners. This is not a new phenomenon, but it was more understandable in the early years of the technologies. To some degree the fault lies with the manufacturers. Fieldbus communication was marketed as being a way to reduce the number of wires required and the size of the cabinets required. To a great degree the real benefits of its ability to support smart instruments was a marketing afterthought, “Look at all the room you can save and, oh by the way, you get this extra information.” As a result, the typical migration project team says, “We already have all these HART instruments that give us the extra data and we’re not pulling any new wire, so why should we change?”
You’ve probably heard me talk before about the idea of operational excellence. In additional to operational excellence, I’ve probably called it manufacturing performance, predictable manufacturing, or even reliable manufacturing.
Have you ever thought about how many average families have been changed by having GPS devices in our cars? Just think back to the (not so) good ol’ pre-GPS days when you pretended you knew where you were going, only to find out you didn’t, and you never heard the end of it. When those wonderful gadgets came along, they put a stop to all the arguments about directions. Yet the change snuck up on us so quietly, it went mostly unnoticed.
Distillation columns are one of the most often used unit operations for separation and purification in the process industries. They can also be some of the most complex to operate and control, because they involve two-phase, multi-stage, counter-current mass and heat transfer (each tray or segment of packing is a theoretical equilibrium stage). The greater the number of trays, the longer the time constants related to composition changes.