Oh no, I forgot... We’re shutting down the plant this weekend!

01 June 2006

Keeping track of what’s going on in a modern plant can be difficult. Here’s what Invensys proposes to do.

Yes, in this complex world we live in, life can be tough for managers who have to make quick decisions about manufacturing plants. We all sense this is true, but to impress it more deeply on our minds, the people at Invensys Process Systems (IPS) put on their own reality show to underline the point.

It was, in fact, perhaps the most elaborate ‘live’ process simulation that has ever been done: Six SAP engineers worked with six Wonderware engineers to create 78 live screens (later reduced to 52 for practical purposes) describing the operations of a simulated gas plant connected with a chemical plant. The web-enabled, continuously running application screens represented all the activities of the plant, from maintenance data to SAP ledger displays.

The simulation was put on for analysts and the trade press at the JFK Library in Boston in April. Here, in a nutshell, is what happened. The CEO of the gas plant received an offer to process a certain quantity of natural gas. If he could process it in four days, he would receive a big bonus, but if he didn’t meet the deadline, there would be a heavy penalty to pay.

Can we do it, he asked the operations manager, who hesitated and then, under pressure, said ‘yes we’ll take the contract.’

Oh, no!
Soon after the hapless manager said yes, he learned a heat exchanger in the fractionator was undergoing scheduled preventative maintenance and the entire unit was down over the weekend, making it impossible to process the order. Yes, maintenance had notified him with an e-mail several weeks ago, but he either didn’t notice it or had forgotten it. Worse, because of the scheduled shutdown, the downstream chemical plant had already arranged for alternate delivery of n-Butane; normally they would receive it as a by-product of
the gas plant’s fractionator. Managers at the chemical plant knew the fractionator would be down but the operations manager at the gas plant apparently didn’t know.

What could operations do?
Maintenance could stop the repair work and bring the fractionator back into operation, but there would be a high cost in overtime. And what could they do with the n-Butane they produced? They can’t send it to the
chemical plant, so they’d probably have to sell it off, at a loss. So much for the big bonus.

Your first question in watching this industrial soap opera would be, How could the operations manager not know an important part of his plant was being shut down? It seems implausible, but IPS says things like this happen all the time in the real world—especially now in the era of deregulation, where plants are buying and selling on the spot market, instead of running continuously as many of them were designed to do.

In the drama’s conflict resolution, the participants coordinated their efforts through IPS’s new InFusion ‘Enterprise Control System’ (ECS) that included a ‘collaboration wall’ where videos and screen displays assisted the managers in making their decisions. The operations manager spotted right away the upcoming maintenance in the fractionator; checking with maintenance (and here we get a plug for Avantis software) learns the repair can be safely delayed for another two weeks. Further collaboration determined what to do with the n-Butane. All ended well and everybody was happy.

Could other major control vendors do what IPS has done? After all, a fully integrated digital control, asset management and business system should be able to deliver the right information to the right people, so they could make appropriate decisions, as did the players in the second half of the little drama.

OPC’s dirty little secret
What underpins the InFusion ECS? It’s primarily extensive collaboration with SAP and Microsoft, and the real
foundation for this activity is Wonderware’s ArchestrA. Whatever else you think of the boys from California, they certainly got one thing right: in the early 1990s, in the pre- ArchestrA days, they put their minds to a ‘device developer kit’ as a tool for building drivers, and began accumulating hundreds of them for their library. (Control market lore has it that the real push for OPC came when other vendors saw how far ahead Wonderware was getting.)

Back to the question, could other vendors deliver a solution like InFusion ECS? Yes, they could probably come close to duplicating its function—that is, if all the equipment in the factory was their own brand. Invensys’ proposition is, we’ll put this all together, no matter where the motors, valves, and transmitters came from, because we have ArchestrA, and we have the software drivers. And if we don’t have the driver, we
know, better than anyone else, how to quickly make one.

So then, what about OPC? If it’s just a matter of getting the right drivers, isn’t OPC the universal device driver, available to anyone? Couldn other vendors deliver the InFusion solution if they exploited OPC?

The answer is, yes and no. More precisely, it’s 10% yes and 90% no. OPC is a great idea going forward in time, because new equipment will generally come with an OPC driver. Of course it introduces an additional software layer and the fewer layers systems have, the better they perform. But, extra layer or not, here’s a dirty little secret: looking at the existing plant, 90% of the equipment does not have—nor will ever have—an OPC driver. OPC is for new digital products, not legacy equipment, which plants are full of. It is ArchestrA, not OPC, that connects with the rest of the world.

The Foxboro intellectuals
So, the InFusion ECS integrates disparate sources of factory data, brings them together in a collaboration wall and delivers the right information to the right people at the right time, and interfaces seamlessly with SAP and Microsoft. If you buy into ECS for these reasons, you’d likely benefit. But, all these taken together are not what’s at the core of InFusion.

Invensys’ Foxboro is a company with a long tradition of intellectual activity, with thinkers like Richard W.
Miller, Ed Bristol, and Greg Shinskey guiding the company. While these men concentrated on instrumentation and advanced control strategies, today’s think tank is centred around Peter Martin. Dr.
Martin and his team have spent years studying and publishing books and papers about what makes, and
what doesn’t make, industrial companies work. In the past three years the team has been concentrating on
how they could translate this activity into meaningful algorithms that can help manufacturing plants.

Dr. Martin has made an important discovery that at first, seems counter-intuitive. Ask yourself this question: If a plant’s maintenance department could do a perfect 100% job, and keep the plant it top repair, so that there was no machine downtime, would that not be the way to maximum profitability? Imagine that: the
technicians did such a good job that nothing ever broke down! Surely every plant would want this.

But no, says Dr. Martin, it’s not true. The maintenance’s department is trying to achieve maximum availability of plant equipment, while the operations department is pushing for maximum utilisation of the equipment, run counter to each other.

Maximising a plant’s economic value does not result from pushing maintenance to achieve optimum
availability and at the same time stretching the operations department to achieve maximum utilisation. It comes from a recognition of the limitations of the two departments and striving to achieve a balance between the two. Dr. Martin and his group have figured out how to quantitatively measure availability and utilisation and analytically determine the optimum balance. This is the intellectual core of InFusion, this is what Invensys brings to the table that nobody else has.

Dr. Martin has a quick example to help those hearing these ideas for the first time to grasp their significance. A certain gas processing plant running 48 compressors achieved 85% utilisation by running them at full speed. ‘Not bad,’ some would say. But, on the average, three compressors would break down a
month and require repair. This is why the utilisation was 85% and not 100%.

By installing variable speed drives and doing some experimentation, the company found that running the
compressors at 98% of full speed would only cause one of them to break down every six months. The utilisation increased to 92%. ‘This may be counter-intuitive,’ says Dr. Martin, ‘decreasing the instant
utilisation in order to increase the overall utilisation.’

Measuring the effective availability and utilisation of the plant and making these business asset valuations in real-time is not a trivial task, but it is the course Invensys has charted. ‘We need to get back to our
measurement roots,’ said Dr. Martin, ‘only now we need to measure other things.’

Foxboro has a history of bringing brilliant thinking to the market, and then stumbling on some of the initial details. In 1987 when it launched its Ethernet-based I/A, the system response was painfully slow at times, and some of its first surface mounted printed circuit cards were manufacturing disasters. It was schadenfreude for Foxboro’s competitors. But the ideas were sound and eventually the company got a firm grip on them and put them right. If Invensys takes a similar course and sticks with InFusion, it will see rewards.


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